科尔沁沙地小叶锦鸡儿群落生长季土壤水分动态和蒸散量估算

Soil Moisture Dynamics and Evapotranspiration of Caragana Microphylla Communities in Growing Season on Horqin Sandy Land

以流动沙丘和不同恢复年限的人工和天然小叶锦鸡儿群落为研究对象,从土壤水分平衡角度对小叶锦鸡儿群落生长季土壤水分动态和蒸散量进行了研究。结果表明,与天然小叶锦鸡儿群落的土壤含水量相比,人工小叶锦鸡儿群落内土壤含水量较低,且呈现出随植被生长发育年限的增加而不断减少的趋势;从土层垂直方向看,流动沙丘土壤含水量较稳定,6年生和天然小叶锦鸡儿群落土壤含水量大致随深度的增加而逐渐增加,但11年生和22年生小叶锦鸡儿群落土壤含水量基本呈下降趋势,绝大多数土层含水量均低于1.50%,水分状况较差;在生长季,人工植被区绝大部分的降雨都通过蒸散丧失,在时间分布上,各样地蒸散量呈现单峰型曲线模式。

Soil moisture dynamics and evapotranspiration of Caragana microphylla communities with different ages were studied based on the soil water balance theory. Results showed that compared with natural C. microphylla community, the soil moisture content of artificial vegetation was lower and continually de- creased along with increase in age. The vertical change of soil moisture showed the tendency of increasing with soil depth in the 6-year-old and natural C. microphylla communities, while performed a reserved trend in the 11 and 22-year-old C. microphylla communities, and their soil moisture content in most layers were lower than 1.50%. Most precipitation lost through evapotranspiration during growing season and the temporal distribution of evapotranspiration had a single-peak curve.