http://hdl.handle.net/2027.42/49252 2013-05-24T18:28:49Z http://hdl.handle.net/2027.42/97540 Leaf color polymorphism as a mechanism of within-individual resource partitioning in the purple pitcher plant, Sarracenia purpurea. Effinger, Kendall Resource partitioning occurs when two or more species have evolved traits that allow them to use a shared limiting resource in different ways, thereby reducing competition and promoting coexistence. In principle, the same phenomenon could occur between tissues of a single individual, if those tissues shared a limiting resource. In nitrogen deficient environments, like bogs, carnivorous plants such as Sarracenia purpurea, the purple pitcher plant, have evolved leaves modified to capture insects and acquire nitrogen from insects. Unlike most plants, whose leaves are nearly identical in appearance, individual pitcher plants have leaves (pitchers) that differ substantially in relative amounts of red and green coloration, i.e. they display leaf color polymorphism. This study addresses the possibility that pitcher plants use leaf color polymorphism as a mechanism of within-individual resource partitioning. I sampled the contents and photographed the hoods of 31 S. purpurea (five pitchers per plant) in Mud Lake Bog in Cheboygan, MI in order to determine the relationship between within-plant color variation and the biomass and types of prey captured. Plants with greater leaf color polymorphism captured significantly more overall prey biomass, hymenopteran biomass, and dipteran biomass, and more species of Hymenoptera, Coleoptera, Hemiptera, and Arachnida. In no case was biomass or number of species negatively correlated with within-plant color variation, suggesting that there is no substantial cost of leaf color polymorphism. These results suggest that purple pitcher plants have pitchers that vary in color, at least in part, because such variation is a mechanism of within-individual resource partitioning Senior Honor's Thesis, Program in the Environment; REU student, summer 2012. 2013-01-01T00:00:00Z http://hdl.handle.net/2027.42/97299 Changes in tree composition of two forestry plots in a northern hardwood forest in Michigan from 1934-1980. Ebbers, Bert C. Tree composition of two forestry plots was studied in a northern hardwood forest in Michigan from 1934-1980. One plot had been selectively thinned from 1934•1954; the other plot was unmanipulated (control). Sugar maple was the leading dominant in both plots. Basswood was second most dominant in the thinned plot and beech was second most dominant in the control plot. As sugar maple increased in importance, beech and ironwood decreased in importance. Sugar maple may limit beech and ironwood due to more successful competition for resources. Basswood decreased in importance after conclusion of cutting in the thinned plot which may relate successful growth of basswood to canopy holes left after cutting. Both plots decreased in diversity from 1934-1980. Big-toothed aspen, white birch, red oak and possibly basswood are only present as large trees in the canopy and are expected to leave the forest as these large trees die (no successful reproduction due to shading out of seedlings). Density decreased as basal area increased for the control plot. Density and basal area decreased due to cutting in the thinned plot (1934-1954); density increased from 1954-1980 to approximately 3/4 of the original density before cutting in 1934. As the thinned plot matures density is expected to decrease. Biogeochemistry of Northern Forests 1980-01-01T00:00:00Z http://hdl.handle.net/2027.42/96208 Effects of anthropogenic structures and a wetland on macroinvertebrate diversity and water chemistry along the Maple River. Alanouf, Carly; Cote, Meredith; Henke, Sam; Hsieh, Ching-Han Aquatic systems play an integral role in wide ranging ecological contexts by providing an outlet of nutrient and chemical buildup. Rivers are particularly vulnerable to deleterious anthropogenic effects given their popularity as transit and recreation waterways. The health of a stream can accurately be assessed using an index of macroinvertebrate diversity as well as a battery of chemical concentration tests. Our study found that the Maple River shows few negative effects of anthropogenic structures on macroinvertebrate health and on overall stream health. The presence of a wetland may also have served to mitigate the possible human effects. General Ecology 2012-01-01T00:00:00Z http://hdl.handle.net/2027.42/96207 The effects of varying coffee ground amendments on earthworm Eisenia fetida biomass in vermicomposting. Fink, Sarah; Hong, Lauryn; Morrison, Izzy; Wang, Yishi The process of vermicomposting with Eisenia fetida has been regarded as a viable solution to the frequent disposal and waste of used coffee grounds. The effects of coffee grounds on earthworms have yet to be fully understood. In a manipulative experiment with varying ratios of coffee grounds and earthworms, we investigate how the amount of coffee grounds affect total earthworm biomass and also how E. fetida affects the initial nitrogen content of each ratio treatment. It was found that there are no significant relationships between E. fetida biomass and soil/coffee ground mixture pH levels and between E. fetida biomass and the percentage of soil/coffee ground mixture nitrogen. Vermicomposting with coffee grounds continues to stand as a valuable waste reducing process that requires furthering studying to provide conclusive results regarding the optimal quantities of coffee grounds for greater earthworm biomass and the relationships among soil pH, nitrogen content and earthworm biomass. General Ecology 2012-01-01T00:00:00Z