Soil Respiration Rates and Carbon Isotope Emissions under Differing Herbivory and Plant Diversity Treatments in a Restoration Prairie

Abstract

<p>As we attempt to restore native habitat, particularly in the Midwestern United States, we cannot overlook the importance soil microbes play in carbon cycling. Agricultural fields provide different ecosystems for microbes and may have long term effects on restoration efforts. By measuring soil respiration rates and carbon isotope emissions, it is possible to gage variations in the sources of respired carbon. In this project we looked at these two factors under herbivory and non-herbivory condition as well as low and high plant species diversity conditions to examine how these treatments effect sources and pool size of rapidly-cycling carbon. We hypothesize that herbivory will increase soil microbial respiration due to plant over compensation, where plants respond to damage by increasing growth rates, and increased species turnover, a change in species composition and abundance due to disturbance. We also hypothesize that the highest difference in carbon isotopes (C3 versus C4) will be the high diversity regions of herbivory plots. This is because the high diversity sections have a much greater forbes to grass species ratio and herbivory, as stated above, is predicted increases turnover. Understanding long term impacts of agriculture on belowground communities may allow us to improve management of restoration prairies.</p>