Abstract: With the analysis to the change modes of biomasses of Trfolium repens and Lolium perenne on the gradients of the ratio between quick-acting-phosphorus and nitrogen in soil, tilman’s theory of mineral nutrition ratio on the changes of community compositions was verified.The outcomes of binary linear regression between the biomasses of two forage species and quick - acting-phosphours and nitrogen indicated that phosphorus and nitrogen are the factors limiting growths of Trdelium repens and Lolium perenne respectively.Consequently, clover and ryegrass can coexist in the pasture communities by niche differentiation on soil nutrient elements.

Key words: Trifolium repens, Lolium perenne, Quick-acting phosphorus, Quick-acting nitrogen, Niche differentiation

摘要： 通过对白三叶和多年生黑麦草生物量在上壤速效磷氛比例梯度上变化模式的分析,验证了Tilman的群落组成变化的矿质营养比例学说。“以两种牧草生物量分别对土壤速效磷和速效氮二元线性回归的结果表明:磷和氮分别是白三叶和多年生黑麦草生长的限制因子。由此,二者可实现在土壤营养元素上的生态位分化而得以在人工草地群落中共存。

关键词: 白三叶, 多年生黑麦草, 速效磷, 速效氮, 生态位分化