@article {KNZ002041, title = {Increasing effects of chronic nutrient enrichment on plant diversity loss and ecosystem productivity over time}, journal = {Ecology}, volume = {102}, year = {2021}, pages = {e03218}, abstract = {

Human activities are enriching many of Earth\’s ecosystems with biologically limiting mineral nutrients such as nitrogen (N) and phosphorus (P). In grasslands, this enrichment generally reduces plant diversity and increases productivity. The widely demonstrated positive effect of diversity on productivity suggests a potential negative feedback, whereby nutrient-induced declines in diversity reduce the initial gains in productivity arising from nutrient enrichment. In addition, plant productivity and diversity can be inhibited by accumulations of dead biomass, which may be altered by nutrient enrichment. Over longer timeframes, nutrient addition may increase soil fertility by increasing soil organic matter and nutrient pools. We examined the effects of 5-11 years of nutrient addition at 47 grasslands in twelve countries. Nutrient enrichment increased aboveground live biomass and reduced plant diversity at nearly all sites, and these effects became stronger over time. We did not find evidence that nutrient-induced losses of diversity reduced the positive effects of nutrients on biomass, however nutrient effects on live biomass increased more slowly at sites where litter was also increasing, regardless of plant diversity. This work suggests that short-term experiments may underestimate the long-term nutrient enrichment effects on global, grassland ecosystems.

}, keywords = {LTER-KNZ}, doi = {10.1002/ecy.3218}, url = {https://onlinelibrary.wiley.com/doi/10.1002/ecy.3218}, author = {Seabloom, E.W. and Adler, P.B. and Alberti, J. and Biederman, L. and Buckley, Y.M. and Cadotte, M.W. and S.L Collins and Dee, L. and Fay, P.A. and Firn, J. and Hagenah, N. and Harpole, W. S. and Hautier, Y. and Hector, A. and Hobbie, S.E. and Isbell, F. and Knops, J.M.H. and Kimberly J. Komatsu and Laungani, R. and MacDougall, A. and McCulley, R.L. and Moore, J.L. and Morgan, J.W. and Ohlert, T. and Prober, S.M. and Risch, A.C. and Schuetz, M. and Stevens, C.J. and Borer, E.T.} } @article {KNZ002042, title = {Nutrients cause grassland biomass to outpace herbivory}, journal = {Nature Communications}, volume = {11}, year = {2020}, pages = {6036}, keywords = {LTER-KNZ}, doi = {10.1038/s41467-020-19870-y}, url = {http://www.nature.com/articles/s41467-020-19870-y}, author = {Borer, E. T. and Harpole, W. S. and Adler, P. B. and Arnillas, C. A. and Bugalho, M. N. and Cadotte, M. W. and Caldeira, M. C. and Campana, S. and Dickman, C. R. and Dickson, T. L. and Donohue, I. and Eskelinen, A. and Firn, J. L. and Graff, P. and Gruner, D. S. and Heckman, R. W. and Koltz, A. M. and Kimberly J. Komatsu and Lannes, L. S. and MacDougall, A. S. and Martina, J. P. and Moore, J. L. and Mortensen, B. and Ochoa-Hueso, R. and Olde Venterink, H. and Power, S. A. and Price, J. N. and Risch, A. C. and Sankaran, M. and sch{\"u}tz, M. and Sitters, J. and Stevens, C. J. and Virtanen, R. and Wilfahrt, P. A. and Seabloom, E. W.} } @article {KNZ001985, title = {Soil net nitrogen mineralisation across global grasslands}, journal = {Nature Communications}, volume = {10}, year = {2019}, abstract = {

Soil nitrogen mineralisation (Nmin), the conversion of organic into inorganic N, is important for productivity and nutrient cycling. The balance between mineralisation and immobilisation (net Nmin) varies with soil properties and climate. However, because most global-scale assessments of net Nmin are laboratory-based, its regulation under field-conditions and implications for real-world soil functioning remain uncertain. Here, we explore the drivers of realised (field) and potential (laboratory) soil net Nmin across 30 grasslands worldwide. We find that realised Nmin is largely explained by temperature of the wettest quarter, microbial biomass, clay content and bulk density. Potential Nmin only weakly correlates with realised Nmin, but contributes to explain realised net Nmin when combined with soil and climatic variables. We provide novel insights of global realised soil net Nmin and show that potential soil net Nmin data available in the literature could be parameterised with soil and climate data to better predict realised Nmin.

}, keywords = {LTER-KNZ}, doi = {10.1038/s41467-019-12948-2}, url = {http://www.nature.com/articles/s41467-019-12948-2}, author = {Risch, A.C. and Zimmermann, S. and Ochoa-Hueso, R. and sch{\"u}tz, M. and Frey, B. and Firn, J. L. and Fay, P. A. and Hagedorn, F. and E.T. Borer and Seabloom, E. W. and Harpole, W. S. and Knops, J. M. H. and McCulley, R. L. and Broadbent, A. A. D. and Stevens, C. J. and Silveira, M. L. and P. Adler and B{\'a}ez, S. and L.A. Biederman and John M. Blair and Brown, C. S. and Caldeira, M. C. and Scott. L. Collins and Daleo, P. and di Virgilio, A. and Ebeling, A. and Eisenhauer, N. and Esch, E. and Eskelinen, A. and Hagenah, N. and Hautier, Y. and Kirkman, K. P. and MacDougall, A. S. and Joslin L. Moore and Power, S. A. and Prober, S. M. and Roscher, C. and Sankaran, M. and Siebert, J. and Speziale, K. L. and Tognetti, P. M. and Virtanen, R. and Yahdjian, L. and Moser, B.} } @article {KNZ001755, title = {Addition of multiple limiting resources reduces grassland diversity}, journal = {Nature}, volume = {537}, year = {2016}, pages = {93-96}, abstract = {

Niche dimensionality provides a general theoretical explanation for biodiversity\—more niches, defined by more limiting factors, allow for more ways that species can coexist1. Because plant species compete for the same set of limiting resources, theory predicts that addition of a limiting resource eliminates potential trade-offs, reducing the number of species that can coexist2. Multiple nutrient limitation of plant production is common and therefore fertilization may reduce diversity by reducing the number or dimensionality of belowground limiting factors. At the same time, nutrient addition, by increasing biomass, should ultimately shift competition from belowground nutrients towards a one-dimensional competitive trade-off for light3. Here we show that plant species diversity decreased when a greater number of limiting nutrients were added across 45 grassland sites from a multi-continent experimental network4. The number of added nutrients predicted diversity loss, even after controlling for effects of plant biomass, and even where biomass production was not nutrient-limited. We found that elevated resource supply reduced niche dimensionality and diversity and increased both productivity5 and compositional turnover. Our results point to the importance of understanding dimensionality in ecological systems that are undergoing diversity loss in response to multiple global change factors.

}, keywords = {LTER-KNZ}, doi = {10.1038/nature19324}, url = {https://www.nature.com/articles/nature19324}, author = {Harpole, W. S. and L.L. Sullivan and Lind, E.M. and Firn, J. and P. Adler and E.T. Borer and Chase, J. and Fay, P.A. and Hautier, Y. and Hillebrand, H. and MacDougall, A.S. and Seabloom, E.W. and Williams, R. and J.D. Bakker and Cadotte, M.W. and Chaneton, E.J. and Chu, C. and Cleland, E.E. and Antonio, C. and Davies, K.F. and Gruner, D.S. and Hagenah, N. and Kirkman, K. and Knops, J.M.H. and Kimberly J. La Pierre and McCulley, R.L. and Joslin L. Moore and J.W. Morgan and Prober, S.M. and A. Risch and Schuetz, M. and Stevens, C.J. and Wragg, P.D.} } @article {KNZ001747, title = {Climate modifies response of non-native and native species richness to nutrient enrichment}, journal = {Philosophical Transactions of the Royal Society B: Biological Sciences}, volume = {3719371}, year = {2016}, pages = {20150273}, abstract = {

Ecosystem eutrophication often increases domination by non-natives and causes displacement of native taxa. However, variation in environmental conditions may affect the outcome of interactions between native and non-native taxa in environments where nutrient supply is elevated. We examined the interactive effects of eutrophication, climate variability and climate average conditions on the success of native and non-native plant species using experimental nutrient manipulations replicated at 32 grassland sites on four continents. We hypothesized that effects of nutrient addition would be greatest where climate was stable and benign, owing to reduced niche partitioning. We found that the abundance of non-native species increased with nutrient addition independent of climate; however, nutrient addition increased non-native species richness and decreased native species richness, with these effects dampened in warmer or wetter sites. Eutrophication also altered the time scale in which grassland invasion responded to climate, decreasing the importance of long-term climate and increasing that of annual climate. Thus, climatic conditions mediate the responses of native and non-native flora to nutrient enrichment. Our results suggest that the negative effect of nutrient addition on native abundance is decoupled from its effect on richness, and reduces the time scale of the links between climate and compositional change.

}, keywords = {LTER-KNZ}, issn = {0962-8436}, doi = {10.1098/rstb.2015.0273}, url = {https://royalsocietypublishing.org/doi/10.1098/rstb.2015.0273}, author = {Flores-Moreno, H. and P.B. Reich and Lind, E.M. and L.L. Sullivan and Seabloom, E.W. and Yahdjian, L. and MacDougall, A.S. and Reichmann, L.G. and J. Alberti and B{\'a}ez, S. and J.D. Bakker and Cadotte, M.W. and Caldeira, M.C. and Chaneton, E.J. and D{\textquoteright}Antonio, C.M. and Fay, P.A. and Firn, J. and Hagenah, N. and Harpole, W. S. and Iribarne, O. and Kirkman, K.P. and Knops, J.M. H. and Kimberly J. La Pierre and Laungani, R. and Leakey, A.D. B. and McCulley, R.L. and Joslin L. Moore and Pascual, J. and E.T. Borer} }