黄土丘陵区达乌里胡枝子人工草地生产力与土壤水分特征研究

对黄土丘陵区川地和坡地达乌里胡枝子(Lespedezadavurica)人工草地生产力与土壤水分状况的季节变化动态进行比较研究。结果表明,川地达乌里胡枝子人工草地生产力显著高于山坡地,单位面积干重约为山坡地的3倍。不同立地下达乌里胡枝子耔实部分约占地上部分最终生物量得到30%￣40%。川地与山地叶片水分利用效率相近,因而川地达乌里胡枝子在维持高生产力情况下,260cm以下土壤层出现雨季期间及休闲期后均不能够恢复的稳定低湿层。

Study on the Aboveground Biomass Production and Soil Water of Artificial Lespedeza davurica Grasslands in Loess hilly-gully Region

Yearly and seasonal changes of soil water and aboveground biomass of artificial Lespedeza davurica grasslands at different habitats in loess hilly-gully region were comparatively studied. The results showed that the productivity of the lowland Lespedeza davurica grassland was more than 3 times that of planted in slope land; the reproductive part accounted for 30%~40% of total biomass; the leaf water use efficiency of Lespedeza davurica at different habitats were not significantly different, so under high productivity, the soil water below the 260cm maintains at 5.0% yearly and cannot be renewed after rainy and fallow seasons.