@article {KNZ00758,
	title = {Different behavioral patterns of the earthworms Octolasion tyrtaeum and Diplocardia spp . in tallgrass prairie soils: potential influences on plant growth},
	journal = {Biology and Fertility of Soils},
	volume = {34},
	year = {2001},
	pages = {49 -56},
	abstract = {This study addressed differences between Diplocardia spp. (a native North American earthworm) and Octolasion tyrtaeum (an introduced European species), with respect to behavior, influence on soil microbial biomass, and plant uptake of N in tallgrass prairie soils. We manipulated earthworms in PVC-encased soil cores (20 cm diameter) over a 45-day period under field conditions. Treatments included: (1) control with no earthworms, (2) Diplocardia spp. only, and (3) O. tyrtaeum only. Prior to addition of earthworms, seedlings of Andropogon gerardii (a dominant tallgrass) were established in each core, and a dilute solution of 13C-labeled glucose and 15N-labeled (NH4)2SO4 was added to the soil to facilitate examination of earthworm/microbe/plant interactions. We found that Diplocardia spp. were significantly more active than O. tyrtaeum, and quickly assimilated 13C and 15N from the tracer. Individuals of Diplocardia spp. were present at shallower soil depths than O. tyrtaeum throughout the study. Contrary to expectation, this greater activity of Diplocardia spp. did not result in increased plant productivity. Rather, the activity of Diplocardia spp. was associated with less plant growth and smaller amounts of N acquired by A. gerardii seedlings compared to controls or O. tyrtaeum treatments. We observed few significant influences of earthworm treatments on microbial biomass C or N pool sizes, but the microbial C/N ratio was consistently greater in the presence of Diplocardia spp. relative to O. tyrtaeum. Results of this study indicate that activity of earthworms may enhance competition for N between microbes and plants during the growing season in tallgrass prairie.},
	keywords = {LTER-KNZ, grassland, Microbial biomass, nitrogen, Soil invertebrates, Stable isotopes},
	doi = {10.1007/s003740100370},
	author = {Callaham, M.A. Jr. and John M. Blair and Hendrix, P.F.}
}
@inbook {KNZ00721,
	title = {Responses of grassland soil invertebrates to natural and anthropogenic disturbances},
	booktitle = {Invertebrates as Webmasters in Ecosystems},
	year = {2000},
	pages = {43 -71},
	publisher = {CAB International Press},
	organization = {CAB International Press},
	address = {New York, NY},
	abstract = {his chapter aims to (1) summarize the major factors influencing invertebrate abundance and distribution in tallgrass prairie soils, focusing on the responses of selected soil invertebrate groups to natural disturbances (such as fire, grazing and drought); (2) identify potential linkages between changes in soil communities and the effects of disturbances on key plant and soil characteristics or processes; and (3) to discuss potential effects of novel anthropogenic perturbations (altered amounts of precipitation, elevated CO2 and increased N inputs) on soil communities and processes. It focuses on North American tallgrass prairies and draws upon studies undertaken at the Konza Prairie Long-Term Ecological Research site, with results from other grasslands where appropriate.},
	keywords = {LTER-KNZ},
	doi = {10.1079/9780851993942.0043},
	author = {John M. Blair and Todd, T.C. and Callaham, M.A.},
	editor = {Coleman, D.C. and Hendrix, P.F.}
}
@inbook {KNZ00477,
	title = {Influences of earthworms on biogeochemistry},
	booktitle = {Earthworm Ecology and Biogeography in North America},
	year = {1995},
	pages = {125 -156},
	publisher = {CRC Press Inc. Lewis Publishers},
	organization = {CRC Press Inc. Lewis Publishers},
	keywords = {LTER-KNZ},
	author = {John M. Blair and Parmelee, R.W. and Lavelle, P.},
	editor = {Hendrix, P.F.}
}
