摘要
围绕土壤结皮生物是否可以对夜间土壤吸附水输入产生响应展开研究。假定-1.5 MPa作为土壤水分有效性的临界值,通过观测降水后清晨和午后0～3 cm土壤含水量,分析土壤水分的有效性和空间异质性;并利用连续记录气象数据,建立表层土壤含水量与水汽压饱和差数量关系。结果表明：土壤吸附作用提高了土壤水分对土壤结皮生物的有效性,并延长了土壤结皮生物对降水脉冲的响应时段。在古尔班通古特沙漠东南部的不同部位,凝结吸附作用对沙面水分条件影响很大（特别是干旱季节）,水分条件由好到坏依次为：沙垄西坡面、沙垄垄顶、沙垄东坡面和垄间低地。
This study focused the effect of soil moisture sorption on soil microbiotic crust. It was presumed that - 1.5 MPa was the critical value of the soil moisture availability for soil microbiotic crust. After measuring soil （0 - 3 cm in depth） moisture content at 19：00 and 7：00 and recording the meteorological parameters, the soil moisture availability and its spatial heterogeneity were analyzed, and the quantitative relationship between vapor pressure deficit of air and soil moisture content was established. The results reveal that soil moisture sorption can prolong the effect of precipitation pulse and increase the soil moisture availability for soil microbiotic crust. It is also revealed that there is an obvious heterogeneity of soil sorption at the different sites of the longitudinal dune-chains and inter-dune lowlands in the southeastern part of the Gurbantonggut Desert, especially in dry season, and soil moisture content is in an order of dune-chain west slope 〉 dune-chain top 〉 dune-chain east slope 〉 inter-dune lowland.
出处
《干旱区研究》
CSCD
北大核心
2009年第5期744-749,共6页
Arid Zone Research
基金
国家自然科学基金(40725002)
中国科学院重要方向项目(KZCX2-YW-431)
