【摘要】 草原群落蒸发蒸腾是一个由各种因素综合影响的复杂问题。本文在羊草草原退化群落系列上 ,用土柱称重法进行群落蒸发蒸腾日进程观测 ,同时调查群落的有关特征特性 ,深入分析了羊草草原退化群落系列上群落蒸发蒸腾及其影响因素 ,得出 :影响群落蒸发蒸腾的首要因素是大气蒸发力与植物根际土壤含水量。当植物根际土壤供水不足时 ,群落蒸发蒸腾日进程曲线普遍出现双峰值。就植物群落自身特征而言 ,不同退化程度的群落蒸腾不但与群落生物量有关 ,而且还与高蒸腾速率植物种在群落中所占比例大小有关。一般随着放牧强度的增加 ,群落生物量减少 ,群落蒸腾减弱 ,群落蒸散没有明显下降更多还原

【Abstract】 The evaporation and transpiration of the steppe communities is a complex problem that is influenced by many factors.The paper surveyed the daily courses of community evaporation and community transpiration of the steppe by measuring soil column and the relevant characteristics of the communities,and further studied the daily courses and the main factors that influenced the community evaporation and community transpiration on the deteriorrated series of natural Leymus chinensis steppe.The results are as follows;the first factor that influences the community evaporation and community transpiration of the steppe.The results are as follows;the first factor that influences the community evaporation and community transpiration of the steppe is atmospheric evaporation strength and the soil water content in the rhizosphere.The daily course curves of community evaporation and community transpiration of the steppe show doublet bimodal value when soil water content in the rhizosphere is not enough.For characteristics of the community itself.the community transpirations on different deteriorated gradients are relevant not only to community biomass but also to proportoin of the plants that have higher transpiration rates.Generally speaking.with increase of grazed strength,both community transpiration and community biomass decrease,and community evapotranspiration is not decrease obviously.更多还原