Plant species percent cover data: The Diversity and Abundance of Prairie Plant Communties

This study is divided into six experiments that test the influence of many factors on the diversity and abundance of prairie plant communities. Each "community" is a 2.25 meter square plot seeded with the same amount of seeds from 59 different species of plants. The first experiment is a nitrogen-fire-water factorial. The second experiment is a nitrogen-pH factorial. The third experiment is a nitrogen gradient and the fourth experiment is a nitrogen gradient with a diversity of seeds added each year. The fifth experiment is a disturbance gradient and the last experiment has three levels of soil heterogeneity (variance from the mean) for both nitrogen and pH. See trmte86, trmte103, trmte104, trmte105, trmte106, trmte107 for plot layout.

本研究共设置六项实验，旨在探究多类因素对草原植物群落多样性与丰度的影响。每个“群落”为面积2.25平方米的方形样地，播撒来自59种不同植物的等量种子。第一项实验为氮素-火烧-水分全因子实验；第二项实验为氮素-pH值全因子实验；第三项实验为氮素梯度实验；第四项实验为氮素梯度实验，并于每年添加不同多样性水平的种子；第五项实验为干扰梯度实验；第六项实验针对氮素与pH值两个变量，设置了三级土壤异质性水平（即与均值的方差）。样地布局详见trmte86、trmte103、trmte104、trmte105、trmte106、trmte107。