Reproductive output--number of flowering heads: Soil Heterogeneity With Disturbance

This study is one of six experiments (E086, E103, E104, E105, E106, E107, E108) 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. This fifth experiment is a disturbance gradient and this experiment (E107) has three levels of soil heterogeneity (variance from the mean) for both nitrogen and pH.

本研究属于包含E086、E103、E104、E105、E106、E107、E108在内的六项实验之一，旨在探究多种因素对草原植物群落多样性与丰度的影响。每个“群落”均指代一块面积为2.25平方米的样地，该样地均播种等量的59种不同植物的种子。第一项实验为氮-火-水三因素析因实验；第二项实验为氮-pH值析因实验；第三项实验为氮素梯度实验；第四项实验为每年添加不同多样性种子的氮素梯度实验；第五项实验为干扰梯度实验，其中本次实验（E107）针对氮素与pH值设置了三个土壤异质性水平（即相对于均值的方差变异）。