REU: Competitive Dominance at Two Soil Resource Levels: An Experimental Investigation of an Old-Field Community

施肥可以显著改变植物的结构， 草本植物群落和土壤的处理 生育力水平可以让我们深入了解 在自然中共存。 该项目将通过实验测试 竞争与土壤肥力的相互作用 场共同体通过操纵双方的存在占主导地位 物种和土壤资源水平。 实验将 包括完全或部分去除两个主要的 种，鸭茅和一枝黄花，单独 在低（对照）和高（富集）土壤肥力下 程度. 对物种丰富度、多样性和其他 社区的财产将被没收。 以互补 实验中，将不同数量的鸭茅种子播种在一个 新开垦的土地，以测试对社区发展的影响 一个优势物种的初始存在和丰度。 的 这项研究将首次尝试调查 与优势种的竞争对 群落结构在高土壤资源水平下高于低土壤资源水平下。 这些实验的数据将测试一些主要的， 关于共存基础的先前未经检验的理论 在自然群落中的植物中。

Fertilization can dramatically alter the structure of herbaceous plant communities, and the manipulation of soil fertility levels can offer insight into the mechanisms of species coexistence in nature. This project will experimentally test the interaction between competition and soil fertility in an old- field community by manipulating both the presence of dominant species and the level of soil resources. Experiments will consist of complete or partial removals of the 2 dominant species, Dactylis glomerata and Solidago altissima, alone together at low (control) and high (enriched) soil fertility levels. The effect on species richness, diversity, and other community properties will be followed. In complementary experiments, varying amounts of Dactylis seed will be sown in a newly plowed field to test the effects on community development of the initial presence and abundance of a dominant species. The study will be the first attempt to investigate whether competition with the dominant species has a different effect on community structure at high than at low soil resource levels. The data from these experiments will test a number of major, previously untested theories regarding the basis for coexistence among plants in natural communities.