Master's research:

My thesis project investigated relationships between productivity and spider diversity in an agricultural spider community. I conducted my fieldwork in no-till soy fields at Miami University's (http://www.units.muohio.edu/erc/index.htm) Ecology Research Center. Because spiders are food-limited in the field, productivity in this experiment meant food (insect prey) available to spiders. I added detritus (a 50/50 mixture of chopped potatoes and mushrooms) to plots in no-till soy fields in an attempt to create an experimental gradient of productivity. I added detritus twice (in June and July) and sampled insects and spiders three times (July, August, September). Although previous studies have established strong linkages between detritus, the soil detritivote community, and spiders, my detritus additions did not affect insects or spiders. Even though the experiment did not experimentally increase productivity, I found strong relationships between Diptera abundance and spider abundance and diversity. Specifically, the abundance of spiders overall and the sheet-web weaver family (Linyphiidae) were both positively associated with Diptera abundance. The dominant species in the plots, Erigone autumnalis (Araneae:Linyphiidae) was also more abundant where there were more Diptera, which was reflected in a positive relationship between Simpson's index and Diptera abundance. Shannon diversity and evenness were both negatively associated with Diptera, and since richness was not related to Diptera, these relationships are due to shifts in relative abundance rather than a loss or gain of species at different productivity levels.

Meeting presentations:

Riem, J.G., C.M. Buddle, and A.L. Rypstra. 2006. Seasonal and productivity effects on spider abundance and diversity in an annual agricultural ecosystem. Oral presentation at the American Arachnological Society annual meeting, Baltimore, MD.

Riem, J.G., C.M. Buddle, and A.L. Rypstra. 2005. Effects of detritus subsidy on the abundance
and diversity of spiders in an agricultural ecosystem. Oral presentation at the American Arachnological Society annual meeting, Akron, OH.

Riem, J.G., C.M. Buddle, and A.L. Rypstra. 2005. Seasonality and productivity affect ground-
dwelling spider abundance and diversity. Poster presented at the Ecological Society of America annual meeting, Montreal, QC.