Abstract: By analyzing the above-ground biomass and the growth rate of that of the M.sativa communities,and the plant height of M.sativa,and the coverage of the communities in the Chaidamu Basin,the author concludes that the above ground biomass and growth rate of M.sativa communities in the third crop year are more than those of M.sativa communities in the second crop year;there isn't s ignificant difference among the plant height of M.sativa communities(P>0.05)；the coverage of the mixted sowing communities is more than that of the monosowing communities;the proportion of the available grass of the mixted sowing communities keep stable,that of the monosowing communities unstable.

Key words: Chaidamu Basin, Medicago sativa, Biomass, Mixture sowing, Monosowing

摘要： 研究柴达木盆地二龄 、三龄混播与单播紫花苜蓿群落地上生物量、生长速率、株高 、盖度的季节动态变化,结果表明,三龄紫花苜蓿生物量、生长速率均高于二龄,但株高间差异不显著(P>0.05)。混播的盖度高于单播、三龄的盖度高于二龄。混播苜蓿的牧草保持稳定比例,单播则变化较大。

关键词: 柴达木盆地, 紫花苜蓿, 生物量, 混播, 单播