中文摘要：

积雪对温带中高纬度地区早春土壤温度和水分具有调控作用，并对土壤呼吸具有重要影响。利用箱式法观测2012年早春积雪融化阶段古尔班通古特沙漠南缘典型温带荒漠梭梭群落内土壤呼吸的动态变化。结果表明：春季融雪期梭梭群落土壤呼吸变异极大，变化范围为0．2—1．2μmol·m^-2·s^-1，日平均土壤呼吸速率变化呈先增后减趋势，但土壤最大呼吸速率随土壤含水量的减少而减少。融雪期灌丛内外土壤呼吸变化规律相同，梭梭灌丛内土壤呼吸速率显著高于灌丛外。融雪期土壤含水量与最大土壤呼吸具有显著的相关关系，但在日尺度上土壤温度与土壤呼吸具有显著的相关关系。研究表明：积雪融化对土壤呼吸具有显著的激发效应，早春积雪变化对土壤呼吸速率将产生重要影响。

英文摘要：

Snowmelt affects highly the change of soil moisture content and temperature in topsoil in snow thawing season, and hence affects soil respiration in temperate arid land. In snow thawing season in early spring 2012, a carbon flux chamber was used to observe the dynamic change of soil respiration in Haloxylon ammodendron commu- nity in southern marginal zone of the Gurbantonggut Desert. The results showed that the variation of soil respiration rate was significant and ranged from 0.2 to 1.2 μmol · m ^-2 . s ^- 1. In snow thawing season, the mean soil respira- tion rate was increased at first and then decreased, and its maximum value was decreased with the decrease of soil moisture content. Soil respiration under bushwood was significantly higher than that out of the bushwood, and its variation under and out of the bushwood was similar. There was a significant correlation between soil moisture con- tent and maximum soil respiration in snow thawing season, and also a significant correlation between soil tempera- ture and soil respiration at daily scale. The study results revealed that there was a stimulating effect of snow thawing on soil respiration, and the change of snow cover in early spring affected significantly soil respiration in the Gurban- tonggut Desert.