00571nas a2200121 4500008004100000245012200041210006900163260003900232490001400271100002400285700001500309856012500324 2023 eng d00aAre we there yet: Assessing trajectories of two restored prairies to target native prairies over a decadal time frame0 aAre we there yet Assessing trajectories of two restored prairies aLawrence, KSbUniversity of Kansas0 vMS Thesis1 aWeickert, Nathaniel1 aBaer, S.G. uhttp://knz.lternet.edu/content/are-we-there-yet-assessing-trajectories-two-restored-prairies-target-native-prairies-over00513nas a2200145 4500008004100000245010300041210006900144300001000213490000700223100002500230700002000255700002000275700001500295856005700310 2023 eng d00aPersistent decadal differences in plant communities assembled under contrasting climate conditions0 aPersistent decadal differences in plant communities assembled un ae28230 v331 aEckhoff, Kathryn, D.1 aScott, Drew, A.1 aManning, George1 aBaer, S.G. uhttps://onlinelibrary.wiley.com/doi/10.1002/eap.282300566nas a2200121 4500008004100000245012000041210006900161260003900230490002100269100001800290700001500308856012100323 2022 eng d00aThe effects of drought on plant and soil microbial communities and functioning during tallgrass prairie restoration0 aeffects of drought on plant and soil microbial communities and f aLawrence, KSbUniversity of Kansas0 vPhD Dissertation1 aEckhoff, K.D.1 aBaer, S.G. uhttp://knz.lternet.edu/content/effects-drought-plant-and-soil-microbial-communities-and-functioning-during-tallgrass00707nas a2200193 4500008004100000245014700041210006900188300001400257490000800271100002500279700002600304700002300330700002300353700001500376700002000391700002200411700001600433856006400449 2022 eng d00aReciprocal transplant gardens as gold standard to detect local adaptation in grassland species: New opportunities moving into the 21st century0 aReciprocal transplant gardens as gold standard to detect local a a1054-10710 v1101 aJohnson, Loretta, C.1 aGalliart, Matthew, B.1 aAlsdurf, Jacob, D.1 aMaricle, Brian, R.1 aBaer, S.G.1 aBello, Nora, M.1 aGibson, David, J.1 aSmith, A.B. uhttps://onlinelibrary.wiley.com/doi/10.1111/1365-2745.1369500814nas a2200241 4500008004100000245012700041210006900168300001100237490000600248100002200254700002400276700002200300700001700322700002300339700002200362700001500384700001800399700001700417700002700434700002600461700001800487856006700505 2021 eng d00aPatterns and trends of organic matter processing and transport: Insights from the US Long-Term Ecological Research network0 aPatterns and trends of organic matter processing and transport I a1000250 v21 aHarms, Tamara, K.1 aGroffman, Peter, M.1 aAluwihare, Lihini1 aCraft, Chris1 aWieder, William, R1 aHobbie, Sarah, E.1 aBaer, S.G.1 aBlair, J., M.1 aFrey, Serita1 aRemucal, Christina, K.1 aRudgers, Jennifer, A.1 aCollins, S, L uhttps://linkinghub.elsevier.com/retrieve/pii/S266690052100025301453nas a2200457 4500008004100000245012400041210006900165300001600234490000700250100002400257700001900281700001700300700001700317700001500334700002100349700002700370700002500397700002400422700002500446700002500471700002100496700002300517700002600540700001900566700002600585700002200611700001900633700001600652700002500668700002200693700002300715700001900738700002600757700002300783700002100806700002400827700002500851700001900876700002400895856007600919 2021 eng d00aSoDaH: the SOils DAta Harmonization database, an open-source synthesis of soil data from research networks, version 1.00 aSoDaH the SOils DAta Harmonization database an opensource synthe a1843 - 18540 v131 aWieder, William, R.1 aPierson, Derek1 aEarl, Stevan1 aLajtha, Kate1 aBaer, S.G.1 aBallantyne, Ford1 aBerhe, Asmeret, Asefaw1 aBillings, Sharon, A.1 aBrigham, Laurel, M.1 aChacon, Stephany, S.1 aFraterrigo, Jennifer1 aFrey, Serita, D.1 aGeorgiou, Katerina1 ade Graaff, Marie-Anne1 aGrandy, Stuart1 aHartman, Melannie, D.1 aHobbie, Sarah, E.1 aJohnson, Chris1 aKaye, Jason1 aKyker-Snowman, Emily1 aLitvak, Marcy, E.1 aMack, Michelle, C.1 aMalhotra, Avni1 aMoore, Jessica, A. M.1 aNadelhoffer, Knute1 aRasmussen, Craig1 aSilver, Whendee, L.1 aSulman, Benjamin, N.1 aWalker, Xanthe1 aWeintraub, Samantha uhttps://essd.copernicus.org/articles/13/1843/2021/essd-13-1843-2021.pdf01110nas a2200373 4500008004100000245008000041210006900121260001100190490000700201100002300208700001800231700002600249700002500275700002400300700001800324700001500342700001800357700001700375700001800392700002300410700002200433700002200455700002400477700001900501700002200520700001200542700002200554700001800576700002200594700002500616700001900641700002200660856005400682 2021 eng d00aState changes: insights from the U.S. Long Term Ecological Research Network0 aState changes insights from the US Long Term Ecological Research ce034330 v121 aZinnert, Julie, C.1 aNippert, J.B.1 aRudgers, Jennifer, A.1 aPennings, Steven, C.1 aGonzález, Grizelle1 aAlber, Merryl1 aBaer, S.G.1 aBlair, J., M.1 aBurd, Adrian1 aCollins, S, L1 aCraft, Christopher1 aDi Iorio, Daniela1 aDodds, Walter, K.1 aGroffman, Peter, M.1 aHerbert, Ellen1 aHladik, Christine1 aLi, Fan1 aLitvak, Marcy, E.1 aNewsome, Seth1 aO’Donnell, John1 aPockman, William, T.1 aSchalles, John1 aYoung, Donald, R. uhttps://onlinelibrary.wiley.com/toc/21508925/12/500700nas a2200157 4500008004100000245009600041210006900137300000800206490000800214100002700222700002200249700001500271700002500286700002300311856020800334 2020 eng d00aNo difference in herbivory preferences among ecotypes of big bluestem (Andropogon gerardii)0 aNo difference in herbivory preferences among ecotypes of big blu a1510 v1231 aPittenger, Madison, S.1 aMaricle, Keri, L.1 aBaer, S.G.1 aJohnson, Loretta, C.1 aMaricle, Brian, R. uhttps://bioone.org/journals/transactions-of-the-kansas-academy-of-science/volume-123/issue-1-2/062.123.0112/No-Difference-in-Herbivory-Preferences-Among-Ecotypes-of-Big-Bluestem/10.1660/062.123.0112.full03157nas a2200169 4500008004100000245011300041210006900154300001100223490000700234520253800241100001502779700001402794700001602808700002002824700002402844856011902868 2020 eng d00aSoil heterogeneity increases plant diversity after twenty years of manipulation during grassland restoration0 aSoil heterogeneity increases plant diversity after twenty years  ae020140 v303 a

The “environmental heterogeneity hypothesis” predicts that variability in resources promotes species coexistence, but few experiments support this hypothesis in plant communities. A previous 15‐yr test of this hypothesis in a prairie restoration experiment demonstrated a weak effect of manipulated soil resource heterogeneity on plant diversity. This response was attributed to a transient increase in richness following a post‐restoration supplemental propagule addition, occasionally higher diversity under nutrient enrichment, and reduced cover of a dominant species in a subset of soil treatments. Here, we report community dynamics under continuous propagule addition in the same experiment, corresponding to 16–20 yr of restoration, in response to altered availability and heterogeneity of soil resources. We also quantified traits of newly added species to determine if heterogeneity increases the amount and variety of niches available for new species to exploit. The heterogeneous treatment contained a factorial combination of altered nutrient availability and soil depth; control plots had no manipulations. Total diversity and richness were higher in the heterogeneous treatment during this 5‐yr study due to higher cover, diversity, and richness of previously established forbs, particularly in the N‐enriched subplots. All new species added to the experiment exhibited unique trait spaces, but there was no evidence that heterogeneous plots contained a greater variety of new species representing a wider range of trait spaces relative to the control treatment. The richness and cover of new species was higher in N‐enriched soil, but the magnitude of this response was small. Communities assembling under long‐term N addition were dominated by different species among subplots receiving added N, leading to greater dispersion of communities among the heterogeneous relative to control plots. Contrary to the deterministic mechanism by which heterogeneity was expected to increase diversity (greater variability in resources for new species to exploit), higher diversity in the heterogeneous plots resulted from destabilization of formerly grass‐dominated communities in N‐enriched subplots. While we do not advocate increasing available soil N at large scales, we conclude that the positive effect of environmental heterogeneity on diversity can take decades to materialize and depend on development of stochastic processes in communities with strong establishment limitation.

1 aBaer, S.G.1 aAdams, T.1 aScott, D.A.1 aBlair, John, M.1 aCollins, Scott., L. uhttp://knz.lternet.edu/content/soil-heterogeneity-increases-plant-diversity-after-twenty-years-manipulation-during01634nas a2200157 4500008004100000245007500041210006900116300001400185490000700199520109500206100001601301700002101317700001501338700002001353856010301373 2019 eng d00aChanges in potential nitrous oxide efflux during grassland restoration0 aChanges in potential nitrous oxide efflux during grassland resto a1913-19170 v483 a

14 Nitrous oxide efflux from soil is an important ecological process in terms of global climate 15 impacts, stratospheric chemistry, and soil fertility. The effects of grassland restoration on nitrous 16 oxide (N 2 O) efflux in formerly cultivated agricultural soils are not well known. Restoration 17 changes the storage and availability of soil C and N, with potential consequences for N 2 O efflux. 18 We examined changes in potential N 2 O efflux across a 35-year chronosequence of grassland 19 restorations, using lab incubations at moisture levels that maximized N 2 O emissions, to quantify 20 the relationship between N 2 O efflux and soil properties known to change predictably during 21 grassland restoration. We found that restoring cultivated agricultural land to grassland rapidly 22 decreased N 2 O efflux from soils, though native prairie had a potential N 2 O efflux higher than the 23 agricultural land. The oldest restoration had N 2 O efflux 50 times lower than native prairie. 24 Changes in N 2 O efflux were more strongly correlated with N mineralization than C.

1 aScott, D.A.1 aRosenzweig, S.T.1 aBaer, S.G.1 aBlair, John, M. uhttp://knz.lternet.edu/content/changes-potential-nitrous-oxide-efflux-during-grassland-restoration00383nas a2200133 4500008004100000245003600041210003600077300001400113490000700127100001600134700001500150700001700165856006700182 2019 eng d00aCommunity Physiological Ecology0 aCommunity Physiological Ecology a510 - 5180 v341 aWarne, R.W.1 aBaer, S.G.1 aBoyles, J.G. uhttps://linkinghub.elsevier.com/retrieve/pii/S016953471930049702672nas a2200133 4500008004100000245011800041210006900159300001600228490000800244520221200252100001602464700001502480856004302495 2019 eng d00aDiversity patterns from sequentially restored grasslands support the ‘environmental heterogeneity hypothesis’0 aDiversity patterns from sequentially restored grasslands support a1116 - 11220 v1283 a

The ‘environmental heterogeneity hypothesis’ (EHH) has been proposed as a mechanism that enables species coexistence through resource partitioning. In accordance with this hypothesis, plant diversity is predicted to increase with variability in resources, but there has been weak support for this hypothesis from experimental studies. The objectives of this research were to 1) characterize how resource availability and heterogeneity (coefficient of variation) change as plant communities develop using sequentially restored grasslands, 2) determine if resource heterogeneity relates to plant diversity (effective number of species, richness, and evenness), and 3) reveal if the strength of resource heterogeneity–diversity relationships is different among levels of resource availability. We quantified means and coefficients of variation in soil nitrate and light availability in grasslands established on former agricultural lands for different times and their relationship to plant diversity using a geostatistically‐informed design. Nitrate availability decreased exponentially with restoration age, but no directional change in nitrate heterogeneity across the chronosequence occurred due to high resource variability in some restorations. Light availability also decreased exponentially across the chronosequence, but there was no directional change in light heterogeneity. Nitrate heterogeneity was positively correlated with both plant richness and plant effective number of species at high levels of nitrate availability. However, no nitrate heterogeneity correlation was detected at low levels of nitrate availability. Light heterogeneity was positively correlated with plant effective number of species at low levels of light availability. However, no light heterogeneity correlation was detected at high levels of light availability. Plant evenness was not correlated with resource heterogeneity at any resource availability level. These results support the positive heterogeneity–diversity relationship predicted by EHH, and uniquely that this relationship develops within a decade of plant community development, but can be obscured by resource availability.

1 aScott, D.A.1 aBaer, S.G. uhttp://doi.wiley.com/10.1111/oik.0587700509nas a2200121 4500008004100000245011100041210006900152260006100221490002100282100001600303700001500319856005300334 2019 eng d00aEnvironmental heterogeneity effects on diversity and nitrous oxide emissions from soil in restored prairie0 aEnvironmental heterogeneity effects on diversity and nitrous oxi aCarbondale, ILbSouthern Illinois University Carbondale 0 vPhD Dissertation1 aScott, Drew1 aBaer, S.G. uhttps://opensiuc.lib.siu.edu/dissertations/1683/04634nas a2201021 4500008004100000245011700041210006900158300001600227490000800243520186900251100002602120700001702146700002402163700001902187700001702206700002602223700002302249700001802272700001702290700002202307700001902329700001402348700001502362700002402377700001402401700002202415700001702437700002002454700001802474700001702492700002102509700002802530700001702558700002402575700002202599700002602621700002102647700001802668700002402686700002402710700001102734700001902745700001902764700001502783700001402798700001402812700001802826700001202844700001602856700001902872700001902891700001602910700001902926700002002945700002002965700002202985700001103007700001403018700001903032700002403051700002303075700001703098700002503115700001903140700001803159700002003177700001603197700002403213700001803237700001503255700001903270700001603289700003203305700001603337700001703353700001703370700001603387700001803403700001703421700001903438700001403457700001503471700001703486700001103503700001903514700001803533856006103551 2019 eng d00aGlobal change effects on plant communities are magnified by time and the number of global change factors imposed0 aGlobal change effects on plant communities are magnified by time a17867-178730 v1163 a

Global change drivers (GCDs) are expected to alter community structure and consequently, the services that ecosystems provide. Yet, few experimental investigations have examined effects of GCDs on plant community structure across multiple ecosystem types, and those that do exist present conflicting patterns. In an unprecedented global synthesis of over 100 experiments that manipulated factors linked to GCDs, we show that herbaceous plant community responses depend on experimental manipulation length and number of factors manipulated. We found that plant communities are fairly resistant to experimentally manipulated GCDs in the short term (<10 y). In contrast, long-term (≥10 y) experiments show increasing community divergence of treatments from control conditions. Surprisingly, these community responses occurred with similar frequency across the GCD types manipulated in our database. However, community responses were more common when 3 or more GCDs were simultaneously manipulated, suggesting the emergence of additive or synergistic effects of multiple drivers, particularly over long time periods. In half of the cases, GCD manipulations caused a difference in community composition without a corresponding species richness difference, indicating that species reordering or replacement is an important mechanism of community responses to GCDs and should be given greater consideration when examining consequences of GCDs for the biodiversity–ecosystem function relationship. Human activities are currently driving unparalleled global changes worldwide. Our analyses provide the most comprehensive evidence to date that these human activities may have widespread impacts on plant community composition globally, which will increase in frequency over time and be greater in areas where communities face multiple GCDs simultaneously.

1 aKomatsu, Kimberly, J.1 aAvolio, M.L.1 aLemoine, Nathan, P.1 aIsbell, Forest1 aGrman, Emily1 aHouseman, Gregory, R.1 aKoerner, Sally, E.1 aJohnson, D.S.1 aWilcox, K.R.1 aAlatalo, Juha, M.1 aAnderson, J.P.1 aAerts, R.1 aBaer, S.G.1 aBaldwin, Andrew, H.1 aBates, J.1 aBeierkuhnlein, C.1 aBelote, R.T.1 aBlair, John, M.1 aBloor, J.M.G.1 aBohlen, P.J.1 aBork, Edward, W.1 aBoughton, Elizabeth, H.1 aBowman, W.D.1 aBritton, Andrea, J.1 aCahill, James, F.1 aChaneton, Enrique, J.1 aChiariello, N.R.1 aCheng, Jimin.1 aCollins, Scott., L.1 aCornelissen, J.H.C.1 aDu, G.1 aEskelinen, Anu1 aFirn, Jennifer1 aFoster, B.1 aGough, L.1 aGross, K.1 aHallett, L.M.1 aHan, X.1 aHarmens, H.1 aHovenden, M.J.1 aJagerbrand, A.1 aJentsch, A.1 aKern, Christel1 aKlanderud, Kari1 aKnapp, Alan, K.1 aKreyling, Juergen1 aLi, W.1 aLuo, Yiqi1 aMcCulley, R.L.1 aMcLaren, Jennie, R.1 aMegonigal, Patrick1 aMorgan, J.W.1 aOnipchenko, Vladimir1 aPennings, S.C.1 aPrevéy, J.S.1 aPrice, Jodi, N.1 aReich, P.B.1 aRobinson, Clare, H.1 aRussell, L.F.1 aSala, O.E.1 aSeabloom, E.W.1 aSmith, M.D.1 aSoudzilovskaia, Nadejda, A.1 aSouza, Lara1 aSuding, K.N.1 aSuttle, B.K.1 aSvejcar, T.1 aTilman, David1 aTognetti, P.1 aTurkington, R.1 aWhite, S.1 aXu, Zhuwen1 aYahdjian, L.1 aYu, Q.1 aZhang, Pengfei1 aZhang, Yunhai uhttps://www.pnas.org/content/early/2019/08/14/181902711602731nas a2200217 4500008004100000245013800041210006900179300001400248490000700262520203500269100002202304700001602326700001602342700001802358700001902376700001502395700001902410700002002429700002102449856004302470 2019 eng d00aLocal adaptation, genetic divergence, and experimental selection in a foundation grass across the US Great Plains’ climate gradient0 aLocal adaptation genetic divergence and experimental selection i a850 - 8680 v253 a

Many prior studies have uncovered evidence for local adaptation using reciprocal transplant experiments. However, these studies are rarely conducted for a long enough time to observe succession and competitive dynamics in a community context, limiting inferences for long-lived species. Furthermore, the genetic basis of local adaptation and genetic associations with climate has rarely been identified. Here, we report on a long-term (6-year) experiment conducted under natural conditions focused on Andropogon gerardii, the dominant grass of the North American Great Plains tallgrass ecosystem. We focus on this foundation grass that comprises 80% of tallgrass prairie biomass and is widely used in 20,000 km2 of restoration. Specifically, we asked the following questions: (a) Whether ecotypes are locally adapted to regional climate in realistic ecological communities. (b) Does adaptive genetic variation underpin divergent phenotypes across the climate gradient? (c) Is there evidence of local adaptation if the plants are exposed to competition among ecotypes in mixed ecotype plots? Finally, (d) are local adaptation and genetic divergence related to climate? Reciprocal gardens were planted with 3 regional ecotypes (originating from dry, mesic, wet climate sources) of Andropogon gerardii across a precipitation gradient (500-1,200 mm/year) in the US Great Plains. We demonstrate local adaptation and differentiation of ecotypes in wet and dry environments. Surprisingly, the apparent generalist mesic ecotype performed comparably under all rainfall conditions. Ecotype performance was underpinned by differences in neutral diversity and candidate genes corroborating strong differences among ecotypes. Ecotype differentiation was related to climate, primarily rainfall. Without long-term studies, wrong conclusions would have been reached based on the first two years. Further, restoring prairies with climate-matched ecotypes is critical to future ecology, conservation, and sustainability under climate change.

1 aGalliart, Matthew1 aBello, Nora1 aKnapp, Mary1 aPoland, Jesse1 aSt Amand, Paul1 aBaer, S.G.1 aMaricle, Brian1 aSmith, Adam, B.1 aJohnson, Loretta uhttp://doi.wiley.com/10.1111/gcb.1453400444nas a2200145 4500008004100000245005700041210005700098300001300155100001500168700001700183700001800200700001700218700001700235856004600252 2019 eng d00aRestoring grassland in the context of climate change0 aRestoring grassland in the context of climate change a310 -3221 aBaer, S.G.1 aGibson, D.J.1 aJohnson, L.C.1 aGibson, D.J.1 aNewman, J.A. uhttps://doi.org/10.1017/9781108163941.02001697nas a2200145 4500008004100000245008600041210006900127300001400196490000700210520115900217100002001376700001701396700001501413856012301428 2018 eng d00aAdvancing theories of ecosystem development through Long-Term Ecological Research0 aAdvancing theories of ecosystem development through LongTerm Eco a554–5620 v683 a

Decades of place-based, long-term ecological research have generated important insights into patterns and processes among ecosystems. Here, we extend a theoretical framework based on Odum's “strategy of ecosystem development”—which predicted distinct attributes of developing and mature ecosystems—in the context of more recent theoretical advancements that predict how long-term changes in the presses (long-term, gradual changes) and pulses (abrupt changes) of drivers that regulate ecosystem functions (press–pulse regimes) can influence their trajectories of development. Our modifications to ecosystem development theories (a) illustrate how press–pulse regimes can cause ecosystems to continue to develop or oscillate around a stable state (pulsed stability) or cause them to decline if the press–pulse regime changes faster than species and communities can adapt, (b) use examples from long-term ecological research of how attributes interact to affect development, and (c) suggest how revised and new theoretical frameworks can integrate long-term ecological research and observatory networks.

1 aKominoski, J.S.1 aGaiser, E.E.1 aBaer, S.G. uhttps://academic.oup.com/bioscience/advance-article-abstract/doi/10.1093/biosci/biy070/5051780?redirectedFrom=fulltext02222nas a2200133 4500008004100000245010000041210006900141300001400210490000800224520176600232100002001998700001502018856005502033 2018 eng d00aDegraded soil increases the performance of a dominant grass, Andropogon gerardii (Big bluestem)0 aDegraded soil increases the performance of a dominant grass Andr a901 - 9110 v2193 a

Dominant grasses can suppress subordinate species in grassland restorations. Examining factors that influence performance of a dominant grass when interacting with subordinate forbs may provide insights for maintaining plant community diversity. The objective of our study was to determine how soils of different restoration ages and functionally different forbs influence the performance (using biomass and tillering rate as proxies) of a dominant grass: Andropogon gerardii. Sites included a cultivated field and two restored prairies (4 or 16 years after restoration) at Konza Prairie (NE Kansas). We hypothesized A. gerardii performance would be greater in more degraded soils and when interacting with legumes. Soil structure, nutrient status, and microbial biomass were measured in soil that was used to conduct the plant interaction study. Andropogon gerardii performance was measured during an 18-week greenhouse experiment using the relative yield index calculated from net absolute tillering rate and final biomass measurements in three soil restoration age treatments combined with four interacting forb treatments. Restoration improved soil structure, reduced plant-available nutrients, and increased microbial biomass. Relative yield index values of A. gerardii were greater with non-legumes than legumes. Andropogon gerardii performed best in degraded soils, which may explain the difficulty in restoring tallgrass prairie diversity in long-term cultivated soil. Results from this study suggest practices that promote soil aggregation and fungal biomass, coupled with including a high abundance of legumes in seed mixes could reduce dominance of A. gerardii and likely increase plant diversity in tallgrass prairie restorations.
 

1 aScott, Drew, A.1 aBaer, S.G. uhttp://link.springer.com/10.1007/s11258-018-0844-002239nas a2200217 4500008004100000245015000041210006900191300001200260490001200272520147500284100002301759700002201782700002401804700002301828700002001851700002001871700001501891700002501906700002301931856006701954 2018 eng d00aDrought tolerance in ecotypes of big bluestem (Andropogon gerardii) relates to above-ground surface area: Results from a common garden experiment0 aDrought tolerance in ecotypes of big bluestem Andropogon gerardi a52 - 600 v246-2473 a

Big bluestem (Andropogon gerardii Vitman) is a dominant tallgrass species that has a wide range in North America with numerous genetically-distinct ecotypes, each adapted to conditions in their native habitat. In an evolutionary context, it was hypothesized that drought adaptation in A. gerardii would relate to plant surface area, where drought-adapted ecotypes were expected to be short with narrow leaves, thin stems, and few leaves per tiller. In the context of individual plants acclimating to reduced rainfall, rainout shelters were hypothesized to cause morphological reductions in surface area of individual plants. Morphological measurements were taken from four genetically-distinct ecotypes of A. gerardii across a precipitation gradient ranging from 500 to 900 mm rain per year at three common garden sites in Colby, Hays, and Manhattan, Kansas, USA. Evolutionary responses to drier soils in A. gerardii resulted in reduction of evaporative surface area from leaves, as drought-adapted plants had fewer and smaller leaves. The most mesic ecotype of A. gerardii had the highest maximum leaf width, stem diameter, and leaf count across sites. There were few effects of environment on morphology in A. gerardii with reduced rainfall, however, indicating genetics plays a more prominent role than environment to influence morphology. We conclude that increased drought tolerance is related to an evolutionary reduction in evaporative surface area.

1 aKramer, Diedre, L.1 aMaricle, Keri, L.1 aHilt, Christina, J.1 aMartin, Nicole, M.1 aUrban, Adam, D.1 aSmart, Cera, M.1 aBaer, S.G.1 aJohnson, Loretta, C.1 aMaricle, Brian, R. uhttps://linkinghub.elsevier.com/retrieve/pii/S036725301830246900562nas a2200121 4500008004100000245014000041210006900181260005000250490002100300100001600321700001500337856008800352 2018 eng d00aEnvironmental and biotic processes influencing floristic composition, quality, integrity, and function in tallgrass prairie assemblages0 aEnvironmental and biotic processes influencing floristic composi aCarbondale, ILb Southern Illinois University0 vPhD Dissertation1 aManning, G.1 aBaer, S.G. uhttps://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=2597&context=dissertations02494nas a2200181 4500008004100000245009100041210006900132300001400201490000800215520189200223100002102115700002402136700002502160700002202185700001502207700002302222856006702245 2018 eng d00aGenetic and environmental influences on stomates of big bluestem (Andropogon gerardii)0 aGenetic and environmental influences on stomates of big bluestem a477 - 4870 v1553 a

Big bluestem (Andropogon gerardii) is a dominant C4 prairie grass that has wide distribution and several genetically distinct ecotypes. Many of the ecotypic adaptations are related to water availability in the native environment. Stomates facilitate photosynthetic gas exchange and regulate water loss from the plant. As such, stomatal size and density represent possible adaptations to conserve water. We hypothesized drought-tolerant ecotypes of big bluestem would have fewer or smaller stomates compared to more mesic ecotypes. Five ecotypes of big bluestem were planted in four common gardens from western Kansas to southern Illinois, USA to determine genetic and environmental influences on stomates. Leaves of all ecotypes of A. gerardii were largely hypostomatous and genetics was a greater influence than environment for stomatal size and density. The drought-tolerant Sand bluestem had larger stomates on abaxial surfaces of leaves, but a lower density compared to most other ecotypes. The most mesic Illinois ecotype and the Kaw cultivar had the greatest density of stomates on abaxial surfaces of leaves. Sand Bluestem had a greater density of stomates on adaxial surfaces of leaves compared to all other ecotypes. Gas exchange measures followed patterns of stomate distribution, where abaxial CO2 uptake rates were greater than adaxial CO2 uptake rates, although differences between leaf surfaces was more pronounced in stomatal density than in CO2 uptake. There were minor differences in size and density of stomates among sites that corresponded with precipitation, although these differences were minor, illustrating the genetic underpinnings of stomates in big bluestem. There is a genetic predisposition for drought-tolerant ecotypes to have fewer stomates, illustrating an evolutionary adaptation to drought tolerance in an important prairie species.
 

1 aVarvel, Nick, A.1 aHilt, Christina, J.1 aJohnson, Loretta, C.1 aGalliart, Matthew1 aBaer, S.G.1 aMaricle, Brian, R. uhttps://linkinghub.elsevier.com/retrieve/pii/S009884721830080702100nas a2200133 4500008004100000245011500041210006900156300001100225490000600236520161100242100002401853700001501877856007401892 2018 eng d00aInterannual variability in climate effects on community assembly and ecosystem functioning in restored prairie0 aInterannual variability in climate effects on community assembly ae023270 v93 a

Community assembly theory attempts to explain factors influencing the composition of communities, which can be governed by deterministic and/or stochastic processes. We used a sequential restoration approach to gain insights into how interannual variation in climate influences community assembly in an agriculture field restored to tallgrass prairie. Species composition and aboveground net primary production (ANPP) were followed for three years in each of three sequentially restored communities, which were established in different years, and sown with the same suite of species using the same live seeding rate for each species. There was a sequence‐by‐age interaction for sown, volunteer, and total species composition (P = 0.001), cover (P < 0.009), diversity (P < 0.024), and richness (P < 0.025). Annual net primary production had a sequence‐by‐age interaction for total, sown, and volunteer species (P < 0.05). In general, species diversity and richness increased over time. We attributed different starting compositions and trajectories in the developing composition of communities and ANPP among sequences to variation in precipitation. Sequences II and III were sown under drought conditions and became dominated by a drought‐resistant agricultural weed that corresponded with delayed establishment and lower ANPP of sown species in those sequences. This study suggests that the effects of drought on community composition vary depending on restoration year, with younger restorations exhibiting greater sensitivity to drought than those that are more established.

1 aManning, George, C.1 aBaer, S.G. uhttps://esajournals.onlinelibrary.wiley.com/doi/abs/10.1002/ecs2.232700438nas a2200133 4500008004100000245004100041210004000082260005700122300001000179100001500189700001400204700001800218856006800236 2018 eng d00aSoil ecosystem services: an overview0 aSoil ecosystem services an overview aCambridgebBurleigh Dodds Science Publishing Limited a17-381 aBaer, S.G.1 aBirge, H.1 aReicosky, Don uhttp://knz.lternet.edu/content/soil-ecosystem-services-overview00471nas a2200121 4500008004100000245009800041210006900139260004400208490002100252100002200273700001500295856003900310 2017 eng d00aDemographic responses of grassland songbirds to rangeland management in the tallgrass prairie0 aDemographic responses of grassland songbirds to rangeland manage aManhattan, KS.bKansas State University0 vPhD Dissertation1 aVerheijen, B.H.F.1 aBaer, S.G. uhttp://hdl.handle.net/2097/35800 03493nas a2200217 4500008004100000245013500041210006900176300000900245490000700254520282100261653001003082653001403092653002203106653001303128653001603141653001603157100001803173700001503191700002003206856004903226 2017 eng d00aEffects of grazing and fire frequency on floristic quality and its relationship to indicators of soil quality in tallgrass prairie0 aEffects of grazing and fire frequency on floristic quality and i a10750 v603 a

Fire and grazing are widely used to manage grasslands for conservation purposes, but few studies have evaluated the effects of these drivers on the conservation value of plant communities measured by the floristic quality index (FQI). Further, the influence of fire and grazing on soil properties and functions are difficult for land managers and restoration practitioners to assess. The objectives of this study were to: (1) quantify the independent and interactive effects of grazing and fire frequency on floristic quality in native tallgrass prairie to provide potential benchmarks for community assessment, and (2) to explore whether floristic quality can serve as an indicator of soil structure and function for more holistic ecosystem assessments. A factorial combination of fire frequencies (1–2, 4, and 20 years return intervals) and grazing (by bison or ungrazed) treatments were sampled for plant species composition, and for several indicators of soil quality in lowland tallgrass prairie. Floristic quality, diversity, and richness were higher in grazed than ungrazed prairie over all fire frequencies (P < 0.05). Available inorganic N, microbial biomass N, total N, and soil bulk density were also higher in grazed prairie soil over all fire frequencies (P < 0.05). Microbial biomass C, total organic C, and total soil N were positively correlated with FQI (P < 0.05). This study shows that floristic quality and soil N pools are more strongly influenced by grazing than fire and that floristic quality can be an indicator of total soil C and N stocks in never cultivated lowland prairie.

10abison10agrassland10aMicrobial biomass10anitrogen10arestoration10aSoil carbon1 aManning, G.C.1 aBaer, S.G.1 aBlair, John, M. uhttps://www.ncbi.nlm.nih.gov/pubmed/2896357202742nas a2200169 4500008004100000245016900041210006900210300001600279490000700295520212900302100001602431700001602447700001402463700001502477700001802492856006202510 2017 eng d00aPhenotypic distribution models corroborate species distribution models: A shift in the role and prevalence of a dominant prairie grass in response to climate change0 aPhenotypic distribution models corroborate species distribution  a4365–43750 v233 a

Phenotypic distribution within species can vary widely across environmental gradients but forecasts of species’ responses to environmental change often assume species respond homogenously across their ranges. We compared predictions from species and phenotype distribution models under future climate scenarios for Andropogon gerardii, a widely distributed, dominant grass found throughout the central United States. Phenotype data on aboveground biomass, height, leaf width, and chlorophyll content were obtained from 33 populations spanning a ~1000 km gradient that encompassed the majority of the species’ environmental range. Species and phenotype distribution models were trained using current climate conditions and projected to future climate scenarios. We used permutation procedures to infer the most important variable for each model. The species-level response to climate was most sensitive to maximum temperature of the hottest month, but phenotypic variables were most sensitive to mean annual precipitation. The phenotype distribution models predict that A. gerardii could be largely functionally eliminated from where this species currently dominates, with biomass and height declining by up to ~60% and leaf width by ~20%. By the 2070s, the core area of highest suitability for A. gerardii is projected to shift up to ~700 km northeastward. Further, short-statured phenotypes found in the present-day short grass prairies on the western periphery of the species’ range will become favored in the current core ~800 km eastward of their current location. Combined, species and phenotype models predict this currently dominant prairie grass will decline in prevalence and stature. Thus, sourcing plant material for grassland restoration and forage should consider changes in the phenotype that will be favored under future climate conditions. Phenotype distribution models account for the role of intraspecific variation in determining responses to anticipated climate change and thereby complement predictions from species distributions models in guiding climate adaptation strategies.

1 aSmith, A.B.1 aAlsdurf, J.1 aKnapp, M.1 aBaer, S.G.1 aJohnson, L.C. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/gcb.1366602504nas a2200145 4500008004100000245015200041210006900193300001000262490000700272520195500279100001602234700001502250700002002265856007302285 2017 eng d00aRecovery and relative influence of root, microbial, and structural properties of soil on physically sequestered carbon stocks in restored grassland0 aRecovery and relative influence of root microbial and structural a50-600 v813 a

Managing soil to sequester C can help mitigate increasing CO2 in the atmosphere. To maximize this ecosystem service, more knowledge of factors influencing C sequestration is needed. The objectives of this study were to (i) quantify recovery of the roots, microbial biomass and composition, and soil structure across a chronosequence of grassland restorations and (ii) use a structural equation model to develop a data-based hypothesis on the relative influence of physical and biological soil properties on the soil C aggregate fraction diagnostic of sequestered C. Belowground plant biomass and tissue quality (C/N ratio), soil microbial biomass C, phospholipid fatty acid (PLFA) concentrations, soil structure, and soil C stocks in the bulk soil and each aggregate fraction were quantified from a cultivated field, prairies restored for 1 to 35-yr (n = 6), and a never-cultivated (native) prairie. Root biomass, microbial biomass C, arbuscular mycorrhizal fungi (AMF) PLFA biomass across the chronosequence increase to resemble native prairie following 35 yr of restoration. Many aspects of soil structure (i.e., bulk density, proportional mass of aggregate fractions, and aggregate mean weighted diameter) and the distribution C among soil fractions, including C in the micro-within-macro aggregate fraction (sequestered C), also became representative of native prairie within 35 yr of restoration. Total soil C stock and physically protected C increased at a similar rate (23 and 27 g C m-2 yr-1) respectively, across the chronosequence. After 35 yr of restoration, 50% of the total C pool was physically protected. The structural equation modeling developed by these data hypothesizes that microbial biomass C and AMF biomass (microbial composition) have the strongest causal influence on physically protected C. This model needs to be tested using independent sites to achieve greater inference.

1 aScott, D.A.1 aBaer, S.G.1 aBlair, John, M. uhttps://dl.sciencesocieties.org/publications/sssaj/abstracts/81/1/5002101nas a2200265 4500008004100000245010300041210006900144300001400213490000700227520132500234653001501559653001701574653001101591653002301602653001301625653002801638653001201666653000901678653000901687100002001696700001501716700001501731700001501746856007401761 2017 eng d00aRestoration and management for plant diversity enhances the rate of belowground ecosystem recovery0 aRestoration and management for plant diversity enhances the rate a355 - 3620 v273 a

The positive relationship between plant diversity and ecosystem functioning has been criticized for its applicability at large scales and in less controlled environments that are relevant to land management. To inform this gap between ecological theory and application, we compared recovery rates of belowground properties using two chronosequences consisting of continuously cultivated and independently restored fields with contrasting diversity management strategies: grasslands restored with high plant richness and managed for diversity with frequent burning (n = 20) and grasslands restored with fewer species that were infrequently burned (n = 15). Restoration and management for plant diversity resulted in 250% higher plant richness. Greater recovery of roots and more predictable recovery of the active microbial biomass across the high diversity management strategy chronosequence corresponded with faster recovery of soil structure. The high diversity grasslands also had greater nutrient conservation indicated by lower available inorganic nitrogen. Thus, mesic grasslands restored with more species and managed for high plant diversity with frequent burning enhances the rate of belowground ecosystem recovery from long-term disturbance at a scale relevant to conservation practices on the landscape

10aAggregates10aBiodiversity10acarbon10aEcosystem function10anitrogen10aphospholipid fatty acid10aprairie10aroot10asoil1 aKlopf, Ryan, P.1 aBaer, S.G.1 aBach, E.M.1 aSix, Johan uhttps://esajournals.onlinelibrary.wiley.com/doi/full/10.1002/eap.150300436nas a2200121 4500008004100000245006600041210006600107260004900173490001500222100001600237700001500253856004600268 2017 eng d00aRestored prairie response to reduction in ectophagous insects0 aRestored prairie response to reduction in ectophagous insects aCarbondale, ILbSouthern Illinois University0 v MS Thesis1 aBlack, S.M.1 aBaer, S.G. uhttps://opensiuc.lib.siu.edu/theses/2331/00535nas a2200121 4500008004100000245016500041210006900206260004900275490001400324100001400338700001500352856004600367 2017 eng d00aThe role of soil heterogeneity in the recruitment of new species and interactions with grasshoppers (Acrididae) and Katydids (Tettigoniidae) in restored prairie0 arole of soil heterogeneity in the recruitment of new species and aCarbondale, ILbSouthern Illinois University0 vMS Thesis1 aAdams, T.1 aBaer, S.G. uhttps://opensiuc.lib.siu.edu/theses/2080/03012nas a2200229 4500008004100000022001300041245013100054210006900185300001400254490000800268520225400276653001702530653001902547653002102566653001702587653002202604100002102626700001702647700001502664700002002679856008302699 2016 eng d a0929139300aChanges in soil properties, microbial biomass, and fluxes of C and N in soil following post-agricultural grassland restoration0 aChanges in soil properties microbial biomass and fluxes of C and a186 - 1940 v1003 a

Understanding the dynamics of soil C and N pools and fluxes following grassland restoration in formerly cultivated soils is needed to assess the capacity of this land-use change to return soil properties and function to pre-disturbance conditions. We examined changes in physical (bulk density) and chemical (pH, available P and N, and total stocks of C and N) properties, microbial biomass C and N, and transformation rates of C and N in soil (0–10 cm depth) across a 35-year chronosequence of prairie restorations and never-cultivated (native) prairie to evaluate the rate and extent to which sowing native perennial plants into formerly cultivated soils returns soil to steady state conditions. Bulk density, available P, and extractable inorganic N decreased exponentially across the chronosequence. Soil pH increased linearly across the chronosequence to exceed that in native prairie soil. Total C and N stocks in cultivated soil were <50% that of native prairie, and increased at rates of 26.2 g C m−2 year−1 and 1.68 g N m−2 year−1 across the chronosequence. In the oldest restoration, total C and N stocks were 55% and 41% higher than the cultivated soil, respectively. Recovery of C and N stocks to levels comparable to native prairie soil was estimated to take 350 years. Microbial biomass C and N increased 5-fold. Potential C mineralization rate was comparable to native prairie soil following two decades of restoration, and exceeded native prairie in the 35-years restoration. In situ soil CO2 efflux reached equilibrium in <30 years. Potential net N mineralization rate, however, did not exhibit a directional change across the restoration chronosequence, but was lowest in the oldest restored grasslands. Thus, cessation of tillage and sowing native vegetation leads to rapid decreases in available N and P, and promotes rapid (decadal scale) recovery of labile soil organic matter pools, but recovery of total C and N pools requires several centuries. This study suggests that soil properties related to nutrient retention and regulation of nutrient availability can be reestablished within the first few decades of restoration, while C sequestration will continue on a longer time scale.

10aBulk density10achronosequence10asoil respiration10aSOM recovery10atallgrass prairie1 aRosenzweig, S.T.1 aCarson, M.A.1 aBaer, S.G.1 aBlair, John, M. uhttps://www.sciencedirect.com/science/article/pii/S0929139316300014?via%3Dihub03068nas a2200145 4500008004100000245011000041210006900151300001300220490000700233520254900240100001502789700002002804700002402824856007402848 2016 eng d00aEnvironmental heterogeneity has a weak effect on diversity during community assembly in tallgrass prairie0 aEnvironmental heterogeneity has a weak effect on diversity durin a94 - 1060 v863 a

Understanding what constrains the persistence of species in communities is at the heart of community assembly theory and its application to conserving and enhancing biodiversity. The “environmental heterogeneity hypothesis” predicts greater species coexistence in habitats with greater resource variability. In the context of community assembly, environmental heterogeneity may influence the variety and strength of abiotic conditions and competitive interactions (environmental filters) to affect the relative abundance of species and biodiversity. We manipulated key resources that influence plant diversity in tallgrass prairie (i.e., soil depth and nitrogen availability) to increase environmental heterogeneity prior to sowing native prairie species into a former agricultural field. We compared variability in nutrient availability, aboveground annual net primary productivity (ANPP), and the composition of species between replicate plots containing soil heterogeneity manipulations and plots with no resource manipulations (n = 4 per treatment) during the first 15 yr of community assembly as a test of the “environmental heterogeneity hypothesis.” The manipulations increased environmental heterogeneity, measured as the coefficient of variation in NO3-N availability and ANPP. Plant diversity, however, was similar and decayed exponentially and indiscriminately over time between the heterogeneity treatments. Species richness declined linearly over time in both heterogeneity treatments, but richness was higher in the more heterogeneous soil 2 yr following a second propagule addition 8 yr after the initial sowing. As a result, there was a lower rate of species loss over time in the more heterogeneous soil (0.60 species yr−1) relative to the control soil (0.96 species yr−1). Communities in each treatment exhibited strong convergence over time resulting from a shift in dominant species across all treatments and a gradual increase in the clonal C4 grass, Andropogon gerardii. We attribute the weak effect of heterogeneity on diversity to increasing dominance of a clonal species, which decreased the scale of soil treatments relative to plant size, dispersal limitation, and absence of a key driver (grazing) known to increase plant diversity under a frequent fire regime. Thus, steering community assembly to attain high biodiversity may depend more on manipulating processes that reduce dominance and facilitate the arrival of new species than promoting environmental heterogeneity.

1 aBaer, S.G.1 aBlair, John, M.1 aCollins, Scott., L. uhttps://esajournals.onlinelibrary.wiley.com/doi/abs/10.1890/15-0888.100508nas a2200121 4500008004100000245012500041210006900166260006000235490001400295100001600309700001500325856004600340 2015 eng d00aRecovery of whole soil conditions through restoration from agriculture and its role in mediating plant-plant competition0 aRecovery of whole soil conditions through restoration from agric aCarbondale, ILbSouthern Illinois University Carbondale0 vMS Thesis1 aScott, D.A.1 aBaer, S.G. uhttps://opensiuc.lib.siu.edu/theses/1826/02155nas a2200229 4500008004100000245009300041210006900134300001300203490000700216520149300223653000901716653001901725653001501744653001301759653001201772653001601784653001501800100001701815700001501832700001601847856006201863 2014 eng d00aColonization and recovery of invertebrate ecosystem engineers during prairie restoration0 aColonization and recovery of invertebrate ecosystem engineers du a456 -4640 v223 a

Ants (Hymenoptera: Formicidae) and earthworms (Oligochaeta) are considered ecosystem engineers because they form biogenic structures in the soil that influence resource supply. The objectives of this study were to quantify recovery dynamics of these invertebrate groups across a chronosequence of restored prairies and elucidate whether changes in the abundance and biomass of ants and earthworms were related to key plant and ecosystem properties. We sampled ants and earthworms from cultivated fields, grasslands restored from 1 to 21 years, and native prairie. Ant abundance and biomass peaked between 5 and 8 years of restoration and abundance was 198 times greater than cultivated fields. Earthworm abundance increased linearly across the chronosequence and became representative of native prairie, but all earthworm populations were dominated by European species. Ant abundance and biomass were positively correlated with plant diversity and plant richness, whereas earthworm abundance biomass was only related to surface litter. These results demonstrate that earthworm abundance increases with time since cessation of cultivation and concomitant with prairie establishment, whereas the abundance and biomass of ants are more related to the structure of restored plant communities than time. The dominance of exotic earthworms in these restorations, coupled with their capacity to alter soil properties and processes may represent novel conditions for grassland development.

10aants10achronosequence10aearthworms10aIllinois10aprairie10arestoration10asoil fauna1 aWodika, B.R.1 aBaer, S.G.1 aKlopf, R.P. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/rec.1208400649nas a2200145 4500008004100000245017800041210006900219300001200288490000700300100001700307700001800324700001500342700001800357856012800375 2014 eng d00aComparing nondestructive and destructive methods of measuring leaf chlorophyll content: tracking changes in foliar chlorophyll of five Andropogon gerardii ecotypes (Poaceae)0 aComparing nondestructive and destructive methods of measuring le a511-5180 v521 aCaudle, K.L.1 aJohnson, L.C.1 aBaer, S.G.1 aMaricle, B.R. uhttp://knz.lternet.edu/content/comparing-nondestructive-and-destructive-methods-measuring-leaf-chlorophyll-content-tracking02362nas a2200193 4500008004100000245013800041210006900179300001300248490000700261520172800268653001201996653001402008653001602022653001602038100001602054700001502070700001702085856006602102 2014 eng d00aConvergent and contingent community responses to grass source and dominance during prairie restoration across a longitudinal gradient0 aConvergent and contingent community responses to grass source an a252 -2650 v533 a

Restoring prairie on formerly cultivated land begins by selecting propagule seed sources and the diversity of species to reintroduce. This study examined the effects of dominant grass propagule source (cultivar vs. non-cultivar) and sown propagule diversity (grass:forb sowing ratio) on plant community structure. Two field experiments were established in Kansas and Illinois consisting of identical split plot designs. Dominant grass source was assigned as the whole-plot factor, and sown dominance of grasses (five levels of seeded grass dominance) as the subplot factor. Species density, cover, and diversity were quantified for 5 years. The effect of dominant grass source on the cover of focal grasses, sown species, and volunteer species was contingent upon location, with variation between dominant grass sources observed exclusively in Kansas. Species density and diversity showed regionally convergent patterns in response to dominant grass source. Contrary to our hypotheses, total species density and diversity were not lower in the presence of grass cultivars, the grass source we had predicted would be more competitive. Sown grass dominance effects on the cover of the focal grass species were contingent upon location resulting from establishment corresponding better to the assigned treatments in Illinois. All other cover groups showed regionally convergent patterns, with lower cover of volunteers and higher cover of sown forbs, diversity, and species density in the lowest sown grass dominance treatment in both sites. Thus, decisions regarding the diversity of propagules to reintroduce had more consequence for plant community structure than cultivar or non-cultivar source of dominant grasses.

10aEcotype10agrassland10arestoration10aSeed source1 aKlopf, R.P.1 aBaer, S.G.1 aGibson, D.J. uhttps://link.springer.com/article/10.1007%2Fs00267-013-0209-302416nas a2200229 4500008004100000245011600041210006900157300001300226490000800239520172000247653002401967653001201991653001402003653002402017653001602041100001702057700001502074700001802089700001502107700001602122856004802138 2014 eng d00aFitness among population sources of a dominant species (Andropogon gerardii Vitman) used in prairie restoration0 aFitness among population sources of a dominant species Andropogo a269 -2790 v1403 a

Planting native grasses can provide a source of seed for prairie restorations, but requires knowledge of how the plants that establish will perform. This study sought to determine variation in fitness of population sources of Andropogon gerardii, a dominant grassland species, when grown in a mesic common garden. Using multiple population sources, we tested the hypothesis that plants from populations within the local region would exhibit a ‘home-site advantage’ as measured by higher fitness compared to plants from populations collected from drier regions of the tallgrass prairie ecosystem (up to 986 km west of the common garden). Plants collected from four pristine, never restored population sources from each of three regions (central Kansas, eastern Kansas, and southern Illinois) were raised in the greenhouse from seeds and planted in a common garden in Illinois. To estimate fitness, we used commonly measured traits related to seed production, including flowering tiller number and number of flowering raceme branches, seed number, viability, and percentage germination. There was no evidence of a ‘home-site advantage’ for populations originating from southern Illinois. Rather, there was high within-region variability in fecundity. Plants from southern Illinois had the largest number of raceme branches per plant. Plants from eastern Kansas had the highest number of vegetative tillers per plant. Plants from central Kansas produced the most germinable seeds. Under the current climate, plants from any one of the three regions may be suitable to propagate seeds for restoration, but other traits may vary among populations to affect height, cover, and productivity.

10aAndropogon gerardii10afitness10agrassland10areproductive effort10arestoration1 aGibson, D.J.1 aSendor, G.1 aDonatelli, J.1 aBaer, S.G.1 aJohnson, L. uhttps://doi.org/10.3159/TORREY-D-12-00063.102320nas a2200277 4500008004100000245016200041210006900203300001300272490000600285520145800291653002201749653002201771653001401793653001201807653001401819653000901833100001501842700001701857700002001874700001501894700001901909700001601928700001801944700001701962856006301979 2014 eng d00aNo effect of seed source on multiple aspects of ecosystem functioning during ecological restoration: cultivars compared to local ecotypes of dominant grasses0 aNo effect of seed source on multiple aspects of ecosystem functi a323 -3350 v73 a

Genetic principles underlie recommendations to use local seed, but a paucity of information exists on the genetic distinction and ecological consequences of using different seed sources in restorations. We established a field experiment to test whether cultivars and local ecotypes of dominant prairie grasses were genetically distinct and differentially influenced ecosystem functioning. Whole plots were assigned to cultivar and local ecotype grass sources. Three subplots within each whole plot were seeded to unique pools of subordinate species. The cultivar of the increasingly dominant grass, Sorghastrum nutans, was genetically different than the local ecotype, but genetic diversity was similar between the two sources. There were no differences in aboveground net primary production, soil carbon accrual, and net nitrogen mineralization rate in soil between the grass sources. Comparable productivity of the grass sources among the species pools for four years shows functional equivalence in terms of biomass production. Subordinate species comprised over half the aboveground productivity, which may have diluted the potential for documented trait differences between the grass sources to influence ecosystem processes. Regionally developed cultivars may be a suitable alternative to local ecotypes for restoration in fragmented landscapes with limited gene flow between natural and restored prairie and negligible recruitment by seed.

10agenetic diversity10agenetic structure10agrassland10aprairie10apropagule10asoil1 aBaer, S.G.1 aGibson, D.J.1 aBenscoter, A.M.1 aReed, L.K.1 aCampbell, R.E.1 aKlopf, R.P.1 aWilland, J.E.1 aWodika, B.R. uhttps://onlinelibrary.wiley.com/doi/full/10.1111/eva.1212403329nas a2200169 4500008004100000245012400041210006900165260004900234490001400283520271100297653003403008653001803042653002103060100001703081700001503098856004603113 2014 eng d00aThe role of deer browsing on plant community development and ecosystem functioning during tallgrass prairie restoration0 arole of deer browsing on plant community development and ecosyst aCarbondale, ILbSouthern Illinois University0 vMS Thesis3 a

Tallgrass prairie in North America has been highly reduced and degraded by human activity (e.g. agriculture) and now human facilitated restoration is necessary to preserve and reestablish the biodiversity, structure and function of this system. In historical tallgrass prairie large ungulates (e.g. Bison bison) were keystone species that regulated many ecosystem properties and functions. Today, restored prairie often lacks these historical ungulates and white-tailed deer (Odocoileus virginianus) have largely assumed the role of dominant ungulates in small, tallgrass prairie restorations. Little is known about how white-tailed deer affect the development of plant communities and ecosystem function during the onset of prairie restoration. In June 2012 an agricultural field was restored to native prairie species in Konza Prairie Biological Station (KPBS) near Manhattan, KS. Immediately following seeding, experimental plots were established and fences were constructed in half of the plots to excluded white-tailed deer. From 2012 to 2013 deer browse of forbs, aboveground biomass (total, sown forbs, sown grasses, volunteer forbs and volunteer grasses), light availability at the soil surface, soil nutrients, and plant community composition were measure inside and outside of exclosures. The first year of this study occurred during a severe drought which diminished in year two, presenting the opportunity to examine the interaction of climate and deer browse on restoration. In plots where deer had access, the percentage of forbs browsed ranged from 1.3 to 10.5%. The effect of deer browsing on aboveground biomass varied across years for each category of biomass. Total biomass appeared to be regulated more strongly by deer than climate, as unbrowsed plots produced similar biomass in each year despite major climatic variation, while browsed plots did not follow this trend. Across all sampling periods, deer browsing increased light availability by 20%. In year two inorganic N was 19% lower in browsed plots, though potential net N mineralization did not vary between treatments. Plant communities were significantly different between years and, between browsed and unbrowsed plots as time and browsing affected community composition, diversity and richness. Deer browsing increased diversity and richness by 24% and 22% respectively. Community composition was most greatly affected by browsing in year one corresponding to the highest rates of browsing and greatest differences in aboveground biomass. These results indicate that deer can have substantial effects on the initial establishment of prairie communities as well as resource availability from the onset of restoration.

10aEcology; Conservation biology10aPlant biology10arange management1 aHarris, P.T.1 aBaer, S.G. uhttps://opensiuc.lib.siu.edu/theses/1515/02869nas a2200133 4500008004100000245011800041210006900159260004900228490002200277520235400299100001602653700001502669856005102684 2013 eng d00aCommunity and ecosystem changes in tallgrass prairie restorations: the effects of population source and diversity0 aCommunity and ecosystem changes in tallgrass prairie restoration aCarbondale, ILbSouthern Illinois University0 vPhD. Dissertation3 a

The overall objective of this study was to quantify the effects of dominant grass propagule source (i.e., cultivar vs. non-cultivar) and seeded diversity of propagules on community structure and ecosystem function during prairie restoration. Two field experiments, and two chronosequences were used to investigate this main objective. The two field experiments were established at the same latitude separated by 620 km (corresponding to a precipitation gradient from eastern Kansas to western Illinois), and consisted of a split plot design, with dominant grass source as the whole-plot factor (2 levels) and seeded dominance of grasses as the subplot factor (5 levels). Percent cover of each species in each treatment combination was quantified during the first five years of restoration. Total plant species richness and diversity were not adversely affected by cultivars in Kansas or Illinois. The effect of the dominant grass population source on the cover of focal grasses, planted species, and volunteer species were contingent upon location. By the fifth year of restoration, diversity and richness were greatest, and cover of volunteer species was lowest in the low grass dominance (i.e., high diversity) treatment. ANPP, as well as total, microbial, and mineralizable pools of C and N were measured to quantify ecosystem function in these two field experiments. Changes in ecosystem function in Kansas and Illinois were primarily driven by time and regional abiotic differences, not propagule source or seeded diversity. The effect of plant species diversity on ecosystem function was further investigated at a landscape scale by developing and sampling two chronosequences of high (HDC; n=20) and low diversity (LDC; n=15) prairies spanning over two decades of restoration in northwestern Illinois. In general most metrics of ecosystem function in both chronosequences moved towards levels measured in remnant prairies. While the constituent prairies of the HDC had higher species richness, diversity, and more rapidly increasing root biomass than the fields of the LDC, recovery of other important ecosystem functions including aboveground net primary productivity, total, microbial, and mineralizable soil C, and soil aggregate mean weighted diameter were achieved equally well with either high or low diversity prairie plantings.

1 aKlopf, R.P.1 aBaer, S.G. uhttp://opensiuc.lib.siu.edu/dissertations/684/02689nas a2200289 4500008004100000245013800041210006900179300001500248490000800263520178200271653002202053653001702075653002002092653002302112653001302135653001802148653001902166653002602185653001502211653001802226100001602244700001702260700001802277700001502295700001602310856007302326 2013 eng d00aEnvironmental and genetic variation in leaf anatomy among populations of Andropogon gerardii (Poaceae) along a precipitation gradient0 aEnvironmental and genetic variation in leaf anatomy among popula a1957 -19680 v1003 a

• Premise of the study: Phenotypes of two Andropogon gerardii subspecies, big bluestem and sand bluestem, vary throughout the prairie ecosystem of North America. This study sought to determine the role of genetics and environment in driving adaptive variation of leaf structure in big bluestem and sand bluestem. • Methods: Four populations of big bluestem and one population of sand bluestem were planted in common gardens at four sites across a precipitation gradient from western Kansas to southern Illinois. Internal leaf structure and trichome density of A. gerardii were examined by light microscopy to separate genetic and environmentally controlled traits. Leaf thickness, midrib thickness, bulliform cells, interveinal distance, vein size, and trichome density were quantified. • Key results: At all planting sites, sand bluestem and the xeric population of A. gerardii had thicker leaves and fewer bulliform cells compared with mesic populations. Environment and genetic source population were both influential for leaf anatomy. Leaves from plants grown in mesic sites (Carbondale, Illinois and Manhattan, Kansas) had thicker midribs, larger veins, fewer trichomes, and a greater proportion of bulliform cells compared to plants grown in drier sites (Colby and Hays, Kansas). • Conclusions: Water availability has driven adaptive variation in leaf structure in populations of A. gerardii, particularly between sand bluestem and big bluestem. Genetically based differences in leaves of A. gerardii indicate adaptive variation and evolutionary forces differentiating sand bluestem from big bluestem. Environmental responses of A. gerardii leaves suggest an ability to adjust to drought, even in populations adapted to mesic home environments.

10aadaptive variatio10abig bluestem10abulliform cells10adrought adaptation10aecotypes10aKranz anatomy10aleaf structure10an Andropogon gerardii10apopulation10asand bluestem1 aOlsen, J.T.1 aCaudle, K.L.1 aJohnson, L.C.1 aBaer, S.G.1 aMaricle, B. uhttps://bsapubs.onlinelibrary.wiley.com/doi/full/10.3732/ajb.120062802777nas a2200265 4500008004100000245010900041210006900150300001300219490000700232520196400239653002302203653002102226653002302247653001402270653001602284653001402300653002202314100001702336700001502353700001602368700001502384700001702399700001802416856007702434 2013 eng d00aLimited effects of dominant species population source on community composition during community assembly0 aLimited effects of dominant species population source on communi a429 -4400 v243 a

Question To what extent do dominant species population sources and subordinate species pools affect diversity and composition of an assembling grassland community? Location Illinois, USA. Methods Percentage cover of all species were recorded annually in 36 1-m2 quadrats assigned to a factorial combination of dominant species population source (functionally distinct cultivar or non-cultivar seed source) and designed species pool (three levels varying in species identity, but with equal functional group representation and richness) during the first 4 yr of community assembly in an experimental grassland restoration. Results Univariate and multivariate analyses showed that individual species abundance, life form and community composition differed significantly among designed species pools, but were not strongly affected by population source of the dominant species (cultivar or non-cultivar). There were fewer C4 species in cultivar plots but only in one of three designed species pools during one of 4 yr of community assembly. The number of legume and forb species was higher in cultivar plots, but also only in one of the 4 yr of study. Other changes in species richness and abundance were solely related to successional change. Conclusions Non-dominant species introduced to restore plant communities strongly affects plant community composition, and composition can show fidelity to designed species pools. Only marginal or temporary effects of dominant species seed source were observed in the assembling plant community. Thus, we found no strong evidence that the source of dominant species, in this case cultivars compared to local ecotypes, has consequences for community assembly in the early stages of restoration (1–4 yr). The absence of a strong dominant species source effect may be exacerbated by the assembly of diverse plant communities, resulting in a stronger effect of subordinate species seed mixture in restoration.

10aCommunity assembly10adominant species10aExtended phenotype10agrassland10arestoration10aSeed pool10atallgrass prairie1 aGibson, D.J.1 aBaer, S.G.1 aKlopf, R.P.1 aReed, L.K.1 aWodika, B.R.1 aWilland, J.E. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/j.1654-1103.2012.01475.x03252nas a2200133 4500008004100000245010200041210006900143260004900212490001400261520276500275100001803040700001503058856004503073 2013 eng d00aRegional-climate and local-microbial controls on ecosystem processes during grassland restoration0 aRegionalclimate and localmicrobial controls on ecosystem process aCarbondale, ILbSouthern Illinois University0 vMS Thesis3 a

Root productivity likely has consequences for the composition, activity, and recovery of soil microbial populations and the belowground processes mediated by these organisms. In tallgrass prairie, ecotypic variation potentially exists in response to a strong precipitation gradient across the Great Plains. Thus, ecotypic variation within a species may differentially affect belowground net primary productivity (BNPP), the associated soil microbial community, and may scale up to affect ecosystem processes. The goals of this study were to elucidate: (1) whether ecotype, environment, or an ecotype by environment interaction regulate BNPP of a dominant species (Andropogon gerardii) collected from and reciprocally planted in common gardens across a precipitation gradient, and (2) whether variation in BNPP scales to affect microbial biomass and ecosystem processes. I quantified root biomass, BNPP (using root ingrowth bags), soil microbial biomass, and nutrient mineralization rates in root-ingrowth cores below six population sources of A. gerardii (2 Illinois, 2 eastern Kansas, and 2 central Kansas) established in southern Illinois, eastern Kansas, and central Kansas. An ecotype effect was found on above and belowground net primary productivity, but these findings did not translate to soil response variables. Microbial populations themselves may affect the productivity and composition of prairie species. In a second study, soil ecological knowledge (SEK) was tested by applying a native prairie soil slurry amendment to restoration plots to determine efficacy of this method as a restoration practice. The goals of this two year study were to elucidate: (1) whether a slurry amendment of prairie soil would increase above and belowground productivity and belowground ecosystem processes in a prairie restoration, and (2) to evaluate whether differences in plant diversity will scale to affect belowground productivity and ecosystem processes. I quantified aboveground net primary productivity (ANPP) and species composition, as well as root biomass, belowground net primary productivity (BNPP), soil microbial biomass, and nutrient mineralization rates in root-ingrowth cores installed in treated and control plots. A treatment effect was noted on root biomass and total PLFA biomass; however, there was no treatment effect on cover, ANPP, or soil microbial processes. Though the soil microbial community did represent native prairie soil, there was poor establishment of prairie plant species. These factors may be due to the limited time available for data collection and the lack of precipitation in the second growing season. Longer studies may be necessary to fully examine the effects of soil slurry amendments as restoration tools.

1 aMendola, M.M.1 aBaer, S.G. uhttp://opensiuc.lib.siu.edu/theses/1338/00309nas a2200109 4500008004100000245002400041210002400065260003800089100001500127700001700142856004000159 2013 eng d00aRestoration Ecology0 aRestoration Ecology aNew YorkbOxford University Press1 aBaer, S.G.1 aGibson, D.J. uhttp://www.oxfordbibliographies.com02099nas a2200217 4500008004100000245009900041210006900140300001500209490000800224520142500232653001901657653002301676653001401699653001501713653002101728100001801749700001501767700001701782700001601799856006601815 2013 eng d00aTemporal dynamics of plant community regeneration sources during tallgrass prairie restoration0 aTemporal dynamics of plant community regeneration sources during a1169 -11800 v2143 a

Ecological restoration aims to augment and steer the composition and contribution of propagules for community regeneration in degraded environments. We quantified patterns in the abundance, richness, and diversity of seed and bud banks across an 11-year chronosequence of restored prairies and in prairie remnants to elucidate the degree to which the germinable seed bank, emerged seedlings, belowground buds, and emerged ramets were related to community regeneration. There were no directional patterns in the abundance, richness, or diversity of the germinable seed bank across the chronosequence. Emerged seedling abundance of sown species decreased during restoration. Richness and diversity of all emerged seedlings and non-sown emerged seedling species decreased across the chronosequence. Conversely, abundance and richness of belowground buds increased with restoration age and belowground bud diversity of sown species increased across the chronosequence. Numbers of emerged ramets also increased across the chronosequence and was driven primarily by the number of graminoid ramets. There were no temporal changes in abundance and richness of sown and non-sown emerged ramets, but diversity of sown emerged ramets increased across the chronosequence. This study demonstrates that after initial seeding, plant community structure in restored prairies increasingly reflects the composition of the bud bank.

10achronosequence10aCommunity assembly10adiversity10aPropagules10aSpecies richness1 aWilland, J.E.1 aBaer, S.G.1 aGibson, D.J.1 aKlopf, R.P. uhttps://link.springer.com/article/10.1007%2Fs11258-013-0241-702491nas a2200229 4500008004100000245006900041210006900110260004000179300001300219520176800232653001602000653002102016653002802037653002602065653001602091653003002107100001502137700001702152700001502169700001302184856006402197 2012 eng d00aApplying soil ecological knowledge to restore ecosystem services0 aApplying soil ecological knowledge to restore ecosystem services aOxford, UKbOxford University Press a377 -3933 aEcological restoration is human-facilitated improvement of a degraded environment. This chapter synthesizes the relevance of soil ecological knowledge to restoration along a continuum of ecosystem degradation and in the context of novel ecosystems. At one end of the continuum, mining can result in severe soil degradation and contamination with metals. Restoration of mined sites often focuses on decontamination, and success can be affected by soil heterogeneity, organic matter content, and refugia for soil biota that possess biodegradation pathways. Former agricultural sites can exhibit a wide range of soil and ecosystem legacies, with restoration goals ranging from simply reducing erosion with perennial plants to establishing a suite of historic ecosystem attributes and services through the re-introduction of many species. Although recovery of soil structure and function can coincide with plant establishment, knowledge of soil processes and plant–soil feedbacks have been applied to promote resource heterogeneity and plant diversity, and to reduce non-native species in restored agricultural systems. Even in relatively undisturbed sites with high legacy of native plants and soil, invasions of undesirable species may occur. Restoration of invaded systems may necessitate knowledge of how invaders impact resource availability and capture, as well as potentially complex multi-trophic interactions and feedbacks with soil. Last, restoration of novel ecosystems with new and self-sustaining assemblages of plant species in no-analog environments may require sophisticated consideration of biogeochemistry, plant population and community dynamics, and soil ecology to reintroduce and sustain native species long extirpated from local environments.10aagriculture10aInvasive species10amining; novel ecosystem10aplant–soil feedback10arestoration10asoil ecological knowledge1 aBaer, S.G.1 aHeneghan, L.1 aEviner, V.1 aWall, D. uhttp://dx.doi.org/10.1093/acprof:oso/9780199575923.003.003203088nas a2200157 4500008004100000245011300041210006900154300001300223490000800236520254300244100001702787700001802804700001502822700001602837856007702853 2012 eng d00aEffects of foundation species genotypic diversity on subordinate species richness in an assembling community0 aEffects of foundation species genotypic diversity on subordinate a496 -5070 v1213 a

Foundation (dominant or matrix) species play a key role in structuring plant communities, influencing processes from population to ecosystem scales. However, the effects of genotypic diversity of foundation species on these processes have not been thoroughly assessed in the context of assembling plant communities. We modified the classical filter model of community assembly to include genotypic diversity as part of the biotic filter. We hypothesized that the proportion of fit genotypes (i.e. competitively superior and dominant) affects niche space availability for subordinate species to establish with consequence for species diversity. To test this hypothesis, we used an individual-based simulation model where a foundation species of varying genotypic diversity (number of genotypes and variability among genotypes) competes for space with subordinate species on a spatially heterogeneous lattice. Our model addresses a real and practical problem in restoration ecology: choosing the level of genetic diversity of re-introduced foundation and subordinate species. Genotypic diversity of foundation species significantly affected equilibrium community diversity, measured as species richness, either positively or negatively, depending upon environmental heterogeneity. Increases in genotypic diversity gave the foundation species a wider niche breadth. Under conditions of high environmental heterogeneity, this wider niche breadth decreased niche space for other species, lowering species richness with increased genotypic diversity until the genotypes of the foundation species saturated the landscape. With a low level of environmental heterogeneity, increasing genotypic diversity caused the foundation species niche breadth to be overdispersed, resulting in a weak positive relationship with species richness. Under these conditions, some genotypes are maladapted to the environment lowering fitness of the foundation species. These effects of genotypic diversity were secondary to the larger effects of overall foundation species fitness and environmental heterogeneity. The novel aspect of incorporating genotype diversity in combination with environmental heterogeneity in community assembly models include predictions of either positive or negative relationships between species diversity and genotypic diversity depending on environmental heterogeneity, and the conditions under which these factors are potentially relevant. Mechanistically, differential niche availability is imposed by the foundation species.

1 aGibson, D.J.1 aAlstadt, A.J.1 aBaer, S.G.1 aGeisler, M. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/j.1600-0706.2011.19447.x02500nas a2200205 4500008004100000245008700041210006900128300001300197490000700210520182800217653003302045653002802078653002902106653002902135653002202164100001502186700001502201700001202216856006602228 2012 eng d00aPlant and soil responses to high and low diversity grassland restoration practices0 aPlant and soil responses to high and low diversity grassland res a412 -4240 v493 a

The USDA’s Conservation Reserve Program (CRP) has predominantly used only a few species of dominant prairie grasses (CP2 practice) to reduce soil erosion, but recently has offered a higher diversity planting practice (CP25) to increase grassland habitat quality. We quantified plant community composition in CP25 and CP2 plantings restored for 4 or 8 years and compared belowground properties and processes among restorations and continuously cultivated soils in southeastern Nebraska, USA. Relative to cultivated soils, restoration increased soil microbial biomass (P = 0.033), specifically fungi (P < 0.001), and restored soils exhibited higher rates of carbon (C) mineralization (P = 0.010). High and low diversity plantings had equally diverse plant communities; however, CP25 plantings had greater frequency of cool-season (C3) grasses (P = 0.007). Older (8 year) high diversity restorations contained lower microbial biomass (P = 0.026), arbuscular mycorrhizal fungi (AMF) biomass (P = 0.003), and C mineralization rates (P = 0.028) relative to 8 year low diversity restorations; older plantings had greater root biomass than 4 year plantings in all restorations (P = 0.001). Low diversity 8 year plantings contained wider root C:N ratios, and higher soil microbial biomass, microbial community richness, AMF biomass, and C mineralization rate relative to 4 year restorations (P < 0.050). Net N mineralization and nitrification rates were lower in 8 year than 4 year high diversity plantings (P = 0.005). We attributed changes in soil C and N pools and fluxes to increased AMF associated with C4 grasses in low diversity plantings. Thus, reduced recovery of AMF in high diversity plantings restricted restoration of belowground microbial diversity and microbially-mediated soil processes over time.

10aConservation reserve program10aNitrogen mineralization10aPhospholipid fatty acids10aSoil microbial community10atallgrass prairie1 aBach, E.M.1 aBaer, S.G.1 aSix, J. uhttps://link.springer.com/article/10.1007%2Fs00267-011-9787-004916nas a2200133 4500008004100000245011700041210006900158260004300227490001400270520442400284100001504708700001504723856004404738 2012 eng d00aResponse of regional sources of tallgrass prairie species to variation in climate and soil microbial communities0 aResponse of regional sources of tallgrass prairie species to var aManhattan, KSbKansas State University0 vMS Thesis3 a

Restoration of resilient plant communities in response to environmental degradation is a critical task, and a changing climate necessitates the introduction of plant communities adapted to anticipated future conditions. Ecotypes of dominant species can affect associated organisms as well as ecosystem function. The extent of ecotypic variation in dominant tallgrass prairie species and the consequences of this variation for ecosystem functioning were studied by manipulating two potential drivers of plant community dynamics: climate and the soil microbial community. Climate was manipulated indirectly through the use of reciprocal restorations across a rainfall gradient where regional sources of dominant grasses Andropogon gerardii and Sorghastrum nutans were seeded with 8 other native species that occur in tallgrass prairie. Four dominant grass sources (originating from central Kansas [CKS], eastern Kansas [EKS], southern Illinois [SIL], or a mixture of these) were reciprocally planted within four sites that occurred across a precipitation gradient in western KS (Colby, KS), CKS (Hays, KS), EKS (Manhattan, KS) and SIL (Carbondale, IL). The three grass sources and mixture of sources were sown into plots according to a randomized complete block design at each sites (n=16, 4 plots / block at each site). Aboveground net primary productivity (ANPP) was measured at the end of the 2010 and 2011 growing season at each site. In 2010, total ANPP declined from western to eastern Kansas, but increased across the geographic gradient in 2011. The dominant grasses did not comprise the majority of community ANPP in WKS, CKS or SIL in either year but did contribute most to total ANPP at the EKS site in 2011. In 2010, volunteer forbs comprised the largest proportion of ANPP in WKS, whereas and in both years planted forbs comprised the largest proportion of ANPP in SIL. Ecotypic variation in ANPP of A. gerardii was not evident, but Sorghastrum nutans ANPP exhibited a site by source effect in 2010 that did not suggest a home site advantage. Variation in the competitive environment at each site may have masked ecotypic variation during community assembly. Further, ANPP responses suggest that grasslands in early stages of establishment may respond more stochastically to climatic variation than established grasslands. Longer term studies will clarify whether ecotypes of dominant prairie grasses affect ecosystem function or community trajectories differently during restoration. Ecotypes of dominant species may support different soil microflora, potentially resulting in plant-soil feedback. A second experiment tested for local adaptation of prairie plant assemblages to their soil microbial community. Native plant assemblages from Kansas and Illinois were tested for local adaptation to their `home' soil by reciprocally crossing soil and plant source in a greenhouse experiment. Seeds and soil were obtained from two remnant prairies, one in eastern Kansas and one in central Illinois, with similar species composition but differing climate. Seeds of four species (Andropogon gerardii, Elymus canadensis, Lespedeza capitata, Oligoneuron rigidum) common to both locations were collected, germinated, and transferred to pots to create 4-species assemblages from each region. Non-prairie (NP) soil from the edge of an Illinois agricultural field was also included as an inoculum treatment to increase relevance to restoration. Kansas and Illinois plant assemblages were subjected to a fully factorial combination of soil inocula [with associated microbial communities] (3 sources: KS, IL, NP) and soil sterilization treatment (sterilized or live). Plants were harvested after 20 weeks and soil was analyzed for microbial composition using phospholipid fatty acid (PLFA) markers. Soil sources had different nutrient concentrations and sterilization resulted in a flush of NH4+, which complicated detection of soil microbial effects. However, plant sources did exhibit variation in productivity responses to soil sources, with Kansas plants more responsive to live soil sources than Illinois plants. Despite confounding variation in soil fertility, soil inoculation was successful at manipulating soil microbial communities, and plant sources responded differently to soil sources. Consideration of feedback between soil and plants may be a missing link in steering restoration trajectories.

1 aGoad, R.K.1 aBaer, S.G. uhttp://opensiuc.lib.siu.edu/theses/922/02404nas a2200229 4500008004100000245015000041210006900191300001100260490000700271520161900278653002401897653001801921653001901939653001601958653002801974653002302002653002202025100001802047700001502065700001702080856007702097 2011 eng d00aIntraspecific Variation in Ecophysiology of Three Dominant Prairie Grasses Used in Restoration: Cultivar Versus Non‐Cultivar Population Sources0 aIntraspecific Variation in Ecophysiology of Three Dominant Prair a43 -520 v193 a

Dominant species play crucial roles in determining plant community structure and ecosystem function. Cultivars of the dominant prairie grasses are widely used in prairie restoration and are selected for characters such as high biomass production, increased reproductive output, and stress tolerance. Genetic differences exist between cultivar and non-cultivar population sources of dominant tallgrass prairie species, which may have implications for plant performance in prairie restoration. We measured net photosynthesis (Anet), stomatal conductance (gs), and water use efficiency (WUE) in cultivar and non-cultivar dominant tallgrass prairie species Andropogon gerardii Vitman, Sorghastrum nutans (L.) Nash, and Schizachyrium scoparium (Michx.) Nash in both a greenhouse experiment and an experimental tallgrass prairie restoration. We found indicators of enhanced physiological performance (higher Anet, gs, and/or WUE) in cultivar population sources of all three dominant grass species relative to non-cultivars. For A. gerardii, cultivars exhibited higher Anet and WUE than non-cultivars. For S. nutans, cultivars exhibited higher gs, whereas non-cultivars showed higher WUE. Lastly, cultivars of S. scoparium showed higher WUE than non-cultivar population sources. Our results show that population selection of dominant species in restoration can have consequences for plant performance, which may have implications for competitive interactions that affect community structure (i.e. diversity) and ecosystem function (i.e. aboveground net primary production) during the reassembly of prairie systems.

10aAndropogon gerardii10aEcophysiology10aphotosynthesis10arestoration10aSchizachyrium scoparium10aSorghastrum nutans10atallgrass prairie1 aLambert, A.M.1 aBaer, S.G.1 aGibson, D.J. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/j.1526-100X.2010.00673.x02531nas a2200193 4500008004100000245014200041210007100183300001300254490000700267520185900274653001302133653002102146653001802167653001002185653003402195100001602229700001502245856007702260 2011 eng d00aRoot dynamics of cultivar and non‐cultivar population sources of two dominant grasses during initial establishment of tallgrass prairie0 aRoot dynamics of cultivar and non‐cultivar population sources of a112 -1170 v193 a

Dominance of warm-season grasses modulates tallgrass prairie ecosystem structure and function. Reintroduction of these grasses is a widespread practice to conserve soil and restore prairie ecosystems degraded from human land use changes. Seed sources for reintroduction of dominant prairie grass species include local (non-cultivar) and selected (cultivar) populations. The primary objective of this study was to quantify whether intraspecific variation in developing root systems exists between population sources (non-cultivar and cultivar) of two dominant grasses (Sorghastrum nutans and Schizachyrium scoparium) widely used in restoration. Non-cultivar and cultivar grass seedlings of both species were isolated in an experimental prairie restoration at the Konza Prairie Biological Station. We measured above- and belowground net primary production (ANPP and BNPP, respectively), root architecture, and root tissue quality, as well as soil moisture and plant available inorganic nitrogen (N) in soil associated with each species and source at the end of the first growing season. Cultivars had greater root length, surface area, and volume than non-cultivars. Available inorganic N and soil moisture were present in lower amounts in soil proximal to roots of cultivars than non-cultivars. Additionally, soil NO3–N was negatively correlated with root volume in S. nutans cultivars. While cultivars had greater BNPP than non-cultivars, this was not reflected aboveground root structure, as ANPP was similar between cultivars and non-cultivars. Intraspecific variation in belowground root structure and function exists between cultivar and non-cultivar sources of the dominant prairie grasses during initial reestablishment of tallgrass prairie. Population source selection should be considered in setting restoration goals and objectives.

10acultivar10adominant grasses10alocal ecotype10aRoots10atallgrass prairie restoration1 aKlopf, R.P.1 aBaer, S.G. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/j.1526-100X.2009.00539.x03035nas a2200229 4500008004100000245009300041210006900134300001500203490000700218520227700225653001502502653003902517653002202556653002902578653003102607653002202638100001502660700001502675700001602690700001202706856008702718 2011 eng d00aSoil texture affects soil microbial and structural recovery during grassland restoration0 aSoil texture affects soil microbial and structural recovery duri a2182 -21910 v423 a

Many biotic and abiotic factors influence recovery of soil communities following prolonged disturbance. We investigated the role of soil texture in the recovery of soil microbial community structure and changes in microbial stress, as indexed by phospholipid fatty acid (PLFA) profiles, using two chronosequences of grasslands restored from 0 to 19 years on silty clay loam and loamy fine sand soils in Nebraska, USA. All restorations were formerly cultivated fields seeded to native warm-season grasses through the USDA’s Conservation Reserve Program. Increases in many PLFA concentrations occurred across the silty clay loam chronosequence including total PLFA biomass, richness, fungi, arbuscular mycorrhizal fungi, Gram-positive bacteria, Gram-negative bacteria, and actinomycetes. Ratios of saturated:monounsaturated and iso:anteiso PLFAs decreased across the silty clay loam chronosequence indicating reduction in nutrient stress of the microbial community as grassland established. Multivariate analysis of entire PLFA profiles across the silty clay loam chronosequence showed recovery of microbial community structure on the trajectory toward native prairie. Conversely, no microbial groups exhibited a directional change across the loamy fine sand chronosequence. Changes in soil structure were also only observed across the silty clay loam chronosequence. Aggregate mean weighted diameter (MWD) exhibited an exponential rise to maximum resulting from an exponential rise to maximum in the proportion of large macroaggregates (>2000 μm) and exponential decay in microaggregates (<250 μm and >53 μm) and the silt and clay fraction (<53 μm). Across both chronosequences, MWD was highly correlated with total PLFA biomass and the biomass of many microbial groups. Strong correlations between many PLFA groups and the MWD of aggregates underscore the interdependence between the recovery of soil microbial communities and soil structure that may explain more variation than time for some soils (i.e., loamy fine sand). This study demonstrates that soil microbial responses to grassland restoration are modulated by soil texture with implications for estimating the true capacity of restoration efforts to rehabilitate ecosystem functions.

10aAggregates10aConservation Reserve Program (CRP)10aMicrobial biomass10aPhospholipid fatty acids10aSoil microbial communities10atallgrass prairie1 aBach, E.M.1 aBaer, S.G.1 aMeyer, C.K.1 aSix, J. uhttps://www.sciencedirect.com/science/article/abs/pii/S0038071710003020?via%3Dihub02931nas a2200169 4500008004100000245011900041210006900160300000800229490000600237520236600243100001502609700001602624700001502640700001602655700001202671856007802683 2010 eng d00aContrasting ecosystem recovery on two soil textures: implications for carbon mitigation and grassland conservation0 aContrasting ecosystem recovery on two soil textures implications a5 -0 v13 a

Understanding processes that promote or constrain ecosystem recovery from disturbance is needed to predict the restorative potential of degraded systems. We quantified a suite of ecosystem properties and processes across two chronosequences of restored grasslands on contrasting soil textures to test the hypothesis that restorations on silty clay loam soil would exhibit greater recovery of soil carbon (C) and nitrogen (N) pools and fluxes than on loamy fine sand because soil with higher clay content possesses a greater capacity to physico-chemically protect organic matter. Warm-season grass aboveground net primary productivity was similar between the two soil textures. Root biomass increased and root quality (as indexed by C:N ratio) decreased across both chronosequences. An asymptote in the accumulation of N in roots in the silty clay loam chronosequence resulted in wider C:N ratios of roots than in the loamy fine sand chronosequence. Total soil C (TC) and microbial biomass C (MBC) increased across the silty clay loam chronosequence at 21.2 and 5.7 g C·m−2·yr−1, respectively, and contained >6 times the amount of C in large macroaggregates and nearly 3 times the aggregate mean weighted diameter (MWD) relative to cultivated soil following 15 yrs of restoration. In contrast, there were no changes in TC, MBC, or MWD in the loamy fine sand chronosequence. Total and microbial biomass N increased at 2.0 and 0.27 g N·m−2·yr−1, respectively, across the silty clay loam chronosequence, and restored soil contained nearly 6 times large macroaggregate N than cultivated soil following 15 yrs of restoration. Potential net N mineralization rates declined with years of grass establishment in both soil textures, but overall rates were lower in the silty clay loam soil relative to the loamy fine sand, which was attributed to lower quality root systems, more improved soil structure, and larger microbial biomass. Thus, the potential for restored agricultural lands to mitigate CO2 emissions over the short term cannot be generalized across all soils. Lastly, the low restorative potential of cultivated loamy fine sand soil through grassland restoration within two decades (relevant to many conservation programs) underscores the need to prioritize preservation of remnant sand prairies.

1 aBaer, S.G.1 aMeyer, C.K.1 aBach, E.M.1 aKlopf, R.P.1 aSix, J. uhttps://esajournals.onlinelibrary.wiley.com/doi/full/10.1890/ES10-00004.102329nas a2200229 4500008004100000245007600041210006900117300001100186490000700197520162000204653002401824653001601848653001401864653003201878653002101910653002001931100001901951700001501970700002001985700001702005856007702022 2010 eng d00aDominant grasses suppress local diversity in restored tallgrass prairie0 aDominant grasses suppress local diversity in restored tallgrass  a40 -490 v183 a

Warm-season (C4) grasses commonly dominate tallgrass prairie restorations, often at the expense of subordinate grasses and forbs that contribute most to diversity in this ecosystem. To assess whether the cover and abundance of dominant grass species constrain plant diversity, we removed 0, 50, or 100% of tillers of two dominant species (Andropogon gerardii or Panicum virgatum) in a 7-year-old prairie restoration. Removing 100% of the most abundant species, A. gerardii, significantly increased light availability, forb productivity, forb cover, species richness, species evenness, and species diversity. Removal of a less abundant but very common species, P. virgatum, did not significantly affect resource availability or the local plant community. We observed no effect of removal treatments on critical belowground resources, including inorganic soil N or soil moisture. Species richness was inversely correlated with total grass productivity and percent grass cover and positively correlated with light availability at the soil surface. These relationships suggest that differential species richness among removal treatments resulted from treatment induced differences in aboveground resources rather than the belowground resources. Selective removal of the dominant species A. gerardii provided an opportunity for seeded forb species to become established leading to an increase in species richness and diversity. Therefore, management practices that target reductions in cover or biomass of the dominant species may enhance diversity in established and grass-dominated mesic grassland restorations.

10aAndropogon gerardii10aCompetition10adiversity10amesic grassland restoration10aPanicum virgatum10aspecies removal1 aMcCain, K.N.S.1 aBaer, S.G.1 aBlair, John, M.1 aWilson, G.T. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/j.1526-100X.2010.00669.x00670nas a2200181 4500008004100000245011900041210006900160300001300229490000700242100001500249700001400264700001800278700002000296700001800316700001900334700001600353856011900369 2009 eng d00aNon-target and invasive species in rehabilitated production systems: Ecological impacts, management and future use0 aNontarget and invasive species in rehabilitated production syste a189 -1960 v431 aBaer, S.G.1 aEngle, D.1 aKnops, J.M.H.1 aLangeland, K.A.1 aMaxwell, B.D.1 aMenalled, F.D.1 aSymstad, A. uhttp://knz.lternet.edu/content/non-target-and-invasive-species-rehabilitated-production-systems-ecological-impacts02838nas a2200133 4500008004100000245010600041210006900147300001500216490000700231520235700238100001502595700002002610856007402630 2008 eng d00aGrassland establishment under varying resource availability: A test of positive and negative feedback0 aGrassland establishment under varying resource availability A te a1859 -18710 v893 a

The traditional logic of carbon (C) and nitrogen (N) interactions in ecosystems predicts further increases or decreases in productivity (positive feedback) in response to high and low fertility in the soil, respectively; but the potential for development of feedback in ecosystems recovering from disturbance is less well understood. Furthermore, this logic has been challenged in grassland ecosystems where frequent fires or grazing may reduce the contribution of aboveground litter inputs to soil organic matter pools and nutrient supply for plant growth, relative to forest ecosystems. Further, if increases in plant productivity increase soil C content more than soil N content, negative feedback may result from increased microbial demand for N making less available for plant growth. We used a field experiment to test for feedback in an establishing grassland by comparing aboveground net primary productivity (ANPP) and belowground pools and fluxes of C and N in soil with enriched, ambient, and reduced N availability. For eight years annual N enrichment increased ANPP, root N, and root tissue quality, but root C:N ratios remained well above the threshold for net mineralization of N. There was no evidence that N enrichment increased root biomass, soil C or N accrual rates, or storage of C in total, microbial, or mineralizable pools within this time frame. However, the net nitrogen mineralization potential (NMP) rate was greater following eight years of N enrichment, and we attributed this to N saturation of the microbial biomass. Grassland developing under experimentally imposed N limitation through C addition to the soil exhibited ANPP, root biomass and quality, and net NMP rate similar to the ambient soil. Similarity in productivity and roots in the reduced and ambient N treatments was attributed to the potentially high nitrogen-use efficiency (NUE) of the dominant C4 grasses, and increasing cover of legumes over time in the C-amended soil. Thus, in a developing ecosystem, positive feedback between soil N supply and plant productivity may promote enhanced long-term N availability and override progressive N limitation as C accrues in plant and soil pools. However, experimentally imposed reduction in N availability did not feed back to reduce ANPP, possibly due to shifts in NUE and functional group composition.

1 aBaer, S.G.1 aBlair, John, M. uhttps://esajournals.onlinelibrary.wiley.com/doi/abs/10.1890/07-0417.102116nas a2200241 4500008004100000245007000041210006900111300001300180490000700193520139600200653002401596653001401620653001701634100001701651700001501668700001501683700001901698700001901717700001801736700001901754700002401773856007701797 2008 eng d00aIntegrating soil ecological knowledge into restoration management0 aIntegrating soil ecological knowledge into restoration managemen a608 -6170 v163 a

The variability in the type of ecosystem degradation and the specificity of restoration goals can challenge restorationists’ ability to generalize about approaches that lead to restoration success. The discipline of soil ecology, which emphasizes both soil organisms and ecosystem processes, has generated a body of knowledge that can be generally useful in improving the outcomes of restoration despite this variability. Here, we propose that the usefulness of this soil ecological knowledge (SEK) for restoration is best considered in the context of the severity of the original perturbation, the goals of the project, and the resilience of the ecosystem to disturbance. A straightforward manipulation of single physical, chemical, or biological components of the soil system can be useful in the restoration of a site, especially when the restoration goal is loosely defined in terms of the species and processes that management seeks to achieve. These single-factor manipulations may in fact produce cascading effects on several ecosystem attributes and can result in unintended recovery trajectories. When complex outcomes are desired, intentional and holistic integration of all aspects of the soil knowledge is necessary. We provide a short roster of examples to illustrate that SEK benefits management and restoration of ecosystems and suggest areas for future research.

10aecosystem processes10afeedbacks10aSoil ecology1 aHeneghan, L.1 aMiller, S.1 aBaer, S.G.1 aCallaham, M.A.1 aMontgomery, J.1 aRhoades, C.C.1 aRichardson, S.1 aPauvo-Zuckerman, M. uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/j.1526-100X.2008.00477.x02664nas a2200241 4500008004100000245013500041210006900176300001300245490000700258520183200265653001402097653002102111653001602132653002302148653001602171653002202187100001502209700002402224700002002248700001602268700002002284856011802304 2005 eng d00aSoil heterogeneity effects on tallgrass prairie community heterogeneity: anapplication of ecological theory to restoration ecology0 aSoil heterogeneity effects on tallgrass prairie community hetero a413 -4240 v133 aSpatial heterogeneity of resources can influence plant community composition and diversity in natural communities. We manipulated soil depth (two levels) and nutrient availability (three levels) to create four heterogeneity treatments (no heterogeneity, depth heterogeneity, nutrient heterogeneity, and depth + nutrient heterogeneity) replicated in an agricultural field seeded to native prairie species. Our objective was to determine whether resource heterogeneity influences species diversity and the trajectory of community development during grassland restoration. The treatments significantly increased heterogeneity of available inorganic nitrogen (N), soil water content, and light penetration. Plant diversity was indirectly related to resource heterogeneity through positive relationships with variability in productivity and cover established by the belowground manipulations. Diversity was inversely correlated with the average cover of the dominant grass, Switchgrass (Panicum virgatum), which increased over time in all heterogeneity treatments and resulted in community convergence among the heterogeneity treatments over time. The success of this cultivar across the wide range of resource availability was attributed to net photosynthesis rates equivalent to or higher than those of the native prairie plants in the presence of lower foliar N content. Our results suggest that resource heterogeneity alone may not increase diversity in restorations where a dominant species can successfully establish across the range of resource availability. This is consistent with theory regarding the role of ecological filters on community assembly in that the establishment of one species best adapted for the physical and biological conditions can play an inordinately important role in determining community structure.10agrassland10aPanicum virgatum10arestoration10asoil heterogeneity10aswitchgrass10atallgrass prairie1 aBaer, S.G.1 aCollins, Scott., L.1 aBlair, John, M.1 aFiedler, A.1 aKnapp, Alan, K. uhttp://knz.lternet.edu/content/soil-heterogeneity-effects-tallgrass-prairie-community-heterogeneity-anapplication03493nas a2200205 4500008004100000245009200041210006900133300001300202490000800215520280200223653001403025653001403039653001303053653002203066100001503088700002003103700002403123700002003147856012003167 2004 eng d00aPlant community responses to resource availability and heterogeneity during restoration0 aPlant community responses to resource availability and heterogen a617 -6290 v1393 aAvailability and heterogeneity of resources have a strong influence on plant community structure in undisturbed systems, as well as those recovering from disturbance. Less is known about the role of resource availability and heterogeneity in restored communities, although restoration provides a valuable opportunity to test our understanding of factors that influence plant community assembly. We altered soil nitrogen (N) availability and soil depth during a prairie restoration to determine if the availability and/or heterogeneity of soil resources influenced plant community composition in restored grassland communities. Plant community responses to three levels of N availability (ambient, enriched by fertilization, and reduced by carbon amendment) and two levels of soil depth (deep and shallow) were evaluated. In addition, we evaluated plant community responses to four whole plot heterogeneity treatments created from the six possible combinations of soil N availability and soil depth. The soil depth treatment had little influence on community structure during the first 3 years of restoration. Total diversity and richness declined over time under annual N enrichment, whereas diversity was maintained and richness increased over time in soil with reduced N availability. Non-native species establishment was lowest in reduced-N soil in the initial year, but their presence was negligible in all of the soil N treatments by the second year of restoration. Panicum virgatum, a native perennial C4 grass, was the dominant species in all soil N treatments by year three, but the magnitude of its dominance was lowest in the reduced-N soil and highest in enriched-N soil. Consequently, the relative cover of P. virgatum was strongly correlated with community dominance and inversely related to diversity. The differential growth response of P. virgatum to soil N availability led to a higher degree of community similarity to native prairie in the reduced-N treatment than in the enriched-N treatment. There were no differences in plant community structure among the four whole plot-level heterogeneity treatments, which all exhibited the same degree of similarity to native prairie. Diversity and community heterogeneity in the whole-plot treatments appeared to be regulated by the dominant species’ effect on light availability, rather than soil N heterogeneity per se. Our results indicate that a strong differential response of a dominant species to resource availability in a restored community can regulate community structure, diversity, and similarity to the native (or target) community, but the importance of resource heterogeneity in restoring diversity may be dampened in systems where a dominant species can successfully establish across a range of resource availability.10adiversity10agrassland10anitrogen10atallgrass prairie1 aBaer, S.G.1 aBlair, John, M.1 aCollins, Scott., L.1 aKnapp, Alan, K. uhttp://knz.lternet.edu/content/plant-community-responses-resource-availability-and-heterogeneity-during-restoration03030nas a2200169 4500008004100000245009400041210006900135300001300204490000700217520241300224653002202637100001502659700002002674700002002694700002402714856012202738 2003 eng d00aSoil resources regulate productivity and diversity in newly established tallgrass prairie0 aSoil resources regulate productivity and diversity in newly esta a724 -7350 v843 aIn native tallgrass prairie, soil depth and nitrogen (N) availability strongly influence aboveground net primary productivity (ANPP) and plant species composition. We manipulated these factors in a newly restored grassland to determine if these resources similarly constrain productivity and diversity during the initial three years of grassland establishment. Four types of experimental plots with six treatment combinations of deep and shallow soil at reduced-, ambient-, and enriched-N availability formed the basis of this study. The soil responses to the experimental treatments were examined over three years, and patterns in diversity and productivity were examined in year 3. The soil depth treatment did not significantly affect soil carbon (C) and N pools or ANPP and diversity. A pulse amendment of C added to the soil prior to planting increased soil microbial biomass and decreased potential net N mineralization rates to effectively reduce N availability throughout the study. Nitrogen availability declined over time in nonamended soils as a result of plant establishment, but adding fertilizer N alleviated the increasing immobilization potential of the soil. The level of ANPP was lowest and diversity highest in the reduced-N treatment, whereas the enriched-N treatment resulted in high productivity, but low diversity. As a result, diversity was inversely correlated with productivity in these newly established communities. The same mechanism invoked to explain decreased diversity under nutrient enrichment in old-field ecosystems and native grasslands (e.g., reduced light availability with increased production) was supported in the restored prairie by the positive relationship between ANPP and intercepted light, and a strong correlation between light availability and diversity. The effects of nutrient availability on plant community composition (diversity and richness) were due primarily to the responses of prairie species, as the productivity of early successional, nonprairie species was less than 1% of total ANPP after three years of establishment. These results show that the effects of resource availability on productivity and diversity are similar in young and mature grasslands, and that manipulation of a limiting nutrient during grassland establishment can influence floristic composition, with consequences for long-term patterns of diversity in restored ecosystems.10atallgrass prairie1 aBaer, S.G.1 aBlair, John, M.1 aKnapp, Alan, K.1 aCollins, Scott., L. uhttp://knz.lternet.edu/content/soil-resources-regulate-productivity-and-diversity-newly-established-tallgrass-prairie02696nas a2200205 4500008004100000245009500041210006900136300001500205490000700220520202100227653001402248653001302262653001402275653001402289100001502303700001802318700002002336700001702356856011702373 2002 eng d00aChanges in ecosystem structure and function along a chronosequence of restored grasslands0 aChanges in ecosystem structure and function along a chronosequen a1688 -17010 v123 aChanges in aboveground vegetation, roots, and soil characteristics were examined from a 12-yr chronosequence of formerly cultivated fields restored to native C4 grasses through the Conservation Reserve Program (CRP). Following 6–8 yr in the CRP, the native grasses dominated vegetation composition, and the presence of forbs was negligible. Productivity of the restored grasslands did not exhibit any directional changes with the number of years in the CRP, and productivity was generally higher than native prairie in this region. Over time, the restored grasslands accumulated root biomass of decreasing quality as indicated by increasing root biomass and C:N ratio of roots along the 12-yr chronosequence. Root biomass, root C:N ratio, C storage in roots, and N storage in roots of restored grasslands approached that of native tallgrass prairie within the 12 yr of restoration. Establishment of the perennial vegetation also affected soil physical, chemical, and biological characteristics. Soil bulk density in the surface 10 cm decreased with time since restoration. Total C, microbial biomass C, and C mineralization rates increased as a function of time since restoration. The greatest change in total C occurred in the surface 5 cm, where total C was 26% greater in 12- vs. 2-yr restored grasslands. Extractable soil nitrate and soil N transformations (i.e., net N mineralization rates and net nitrification rates) declined over the restoration chronosequence, but these values were not representative of steady-state conditions due to the high variability in these measures among the native prairies. Although complete restoration of ecosystem structure and function was not the primary intention of the CRP, this study demonstrates that establishment of the matrix vegetation (i.e., native C4 grasses) drives ecosystem processes in the trajectory of the original system. Moreover, restoration may hasten the recovery of soil C pools relative to formerly cultivated systems undergoing natural succession.10aecosystem10afunction10agrassland10astructure1 aBaer, S.G.1 aKitchen, D.J.1 aBlair, John, M.1 aRice, C., W. uhttp://knz.lternet.edu/content/changes-ecosystem-structure-and-function-along-chronosequence-restored-grasslands00614nas a2200133 4500008004100000245013300041210006900174260004300243300001100286490002100297653002200318100001500340856012500355 2001 eng d00aChanges in ecosystem function and effects of environmental complexity on foristic diversity during tallgrass prairie restoration0 aChanges in ecosystem function and effects of environmental compl aManhattan, KSbKansas State University a1 -2040 vPhD Dissertation10atallgrass prairie1 aBaer, S.G. uhttp://knz.lternet.edu/content/changes-ecosystem-function-and-effects-environmental-complexity-foristic-diversity-during01409nas a2200145 4500008004100000245008900041210006900130300001300199490000700212520093600219100001501155700001701170700002001187856005601207 2000 eng d00aAssessment of soil quality in fields with short- and long-term enrollment in the CRP0 aAssessment of soil quality in fields with short and longterm enr a142 -1460 v553 aSurface [5 to10 cm, (2 to 4 in) depth] soil quality was examined from fields representing short and long term enrollment in the Conservation Reserve Program (CRP). Total carbon (C) and nitrogen (N) amounts were similar in soil with recent and long term enrollment in the CRP and were lower than a native prairie field. Active pools of C and N, however, did increase through the CRP. Soil with long term establishment of native grasses in the CRP exhibited 141% and 33% greater microbial biomass C and N, respectively, than soil recently enrolled in the CRP. Total inorganic N was significantly lower in CRP soil with ten versus no growing seasons and was more representative of levels in a native prairie due to reductions in nitrate availability. Our study indicates that CRP promotes soil restoration; however, ten growing seasons are not adequate for recovery of total soil C and N pools at this depth to pre-cultivation levels.1 aBaer, S.G.1 aRice, C., W.1 aBlair, John, M. uhttp://www.jswconline.org/content/55/2/142.abstract02807nas a2200241 4500008004100000245008300041210006900124260005100193300001100244520196600255653003202221653003902253653001702292653002302309653001902332653001802351653002202369100001502391700002002406700002002426700001902446856010002465 1999 eng d00aManipulation of soil resource heterogeneity in a tallgrass prairie restoration0 aManipulation of soil resource heterogeneity in a tallgrass prair aKearney, NEbUniversity of Nebraska at Kearney a78 -873 aPlant species diversity in native prairie ecosystems is influenced by heterogeneity of soil resources, which results from interactions among plant communities, soil properties, topography, and disturbance. Key factors which promote plant diversity in native prairie include soil moisture, rooting depth, and nutrient availability. Most prairie restorations in the Great Plains occur on former agricultural land and the soil template for these restorations has been physically homogenized through tillage practices. The reduction in soil resource heterogeneity in restored prairies may be causally related to low plant species diversity commonly encountered in these sites. To examine the role of soil heterogeneity in restoring prairie ecosystems, replicated blocks (n=4) of 4 plots consisting of different levels of soil heterogeneity were established in an agricultural field. The 4 plot types included: control (least heterogeneous with respect to soil resources), altered plant rooting depth, altered nutrient availability, and combined variation in plant rooting depth and nutrient availability (maximum heterogeneity). Plant rooting depth was varied by burying limestone barriers at 25 cm to create alternating strips of deep and shallow soil. Variation in soil nutrient (inorganic N) availability was established via increased N (+fertilizer), decreased N (+ recalcitrant C), and no change in N. All plots were seeded with the dominant native grasses and >30 forb species. Incorporation of recalcitrant C reduced total inorganic N availability 90% as a result of 98% reduction in available nitrate. Plots containing strips of low N availability exhibited significantly (p < 0.05) greater spatial variability than plots without this manipulation. Thus, the experimental design and methods implemented have increased heterogeneity of soil nutrients, and this will enable us to address the role of variation in soil resources on restoring tallgrass prairie.10aaltered plant rooting depth10aaltered soil nutrient availability10aGreat Plains10alimestone barriers10arecalcitrant C10asoil template10aSpecies diversity1 aBaer, S.G.1 aBlair, John, M.1 aKnapp, Alan, K.1 aSpringer, J.T. uhttp://images.library.wisc.edu/EcoNatRes/EFacs/NAPC/NAPC16/reference/econatres.napc16.sbaer.pdf