祁连山大野口流域土壤温度空间变化特征

Spatial Variation Characteristics of Soil Temperature in Dayekou Basin of Qilian Mountains

选择祁连山大野口为试验流域,研究土壤温度在海拔、坡向、坡度、深度等空间的变化特征。结果表明:1.土壤温度随海拔升高呈波动性降低,降低率约为0.74℃/(100 m);2.阳坡土壤温度比半阳坡高1.3倍、比半阴坡高2.2倍,半阳坡土壤温度比半阴坡高1.6倍;3.土壤温度随坡度增大而略呈降低趋势;4.土壤温度与深度关系为Sdt=-0.0536d+9.192(R^2=0.994),温度随深度降低率约为0.536℃/(10 cm),呈线性函数关系;5.亚高山灌丛林比乔木林土壤温度低1.6倍、比草地低2.3倍,乔木林土壤温度比草地低1.4倍;6.从土壤温度的变化程度分析,高海拔半阴坡灌丛林土壤温度变化最剧烈,低海拔阳坡草地土壤温度变化较小;在0~80 cm土层范围内,表层土壤温度变化最剧烈,40~60 cm土层的温度变化最小。研究可为流域水源涵养功能、水资源管理及利用、林分结构调控及土壤水资源植被承载力等研究提供基础数据和参考资料。

It was more important that monitoring and research on soil temperature under the background of global warming. Dayekou basin of Qilian Mountains in Gansu, China had been chosen the test basin and studied on spatial variation characteristics of soil temperature in this paper. Results showed that： 1. Soil temperature was volatility declining with altitude increased, and soil temperature reduction was about 0.74℃ with the altitude was increased 100 m;2. The soil temperature was 1.3 times higher on sunny slope than half sunny slope, and 2.2 times higher than half shady slope. The soil temperature was 1.6 times higher on half sunny than half shady slope;3. The soil temperature decreased with the slope greater; 4. The relation between soil temperature and its depth was Sat = 0. 0536 d ＋ 0. 0536 （ R2 = 0. 994 ）, and every additional 10 cm soil depth, the temperature decreased about 0. 536 ℃, and the relation function was linear;5. The soil temperature under sub alpine was 1.6 times lower than arbor forest, and 2.3 times lower than grassland. The soil temperature under arbor forest was 1.4 times than grassland ;6. From analysis on degree of spatial variation of soil temperature, the variation of soil temperature under sub alpine was the most severe on high altitude and half shady slope, and the variation of soil temperature under grass- land was the lowest on low altitude slope and sunny or half sunny slope; The variation of surface soil temperature was most severe, and the variation of temperature under soil lay from 40 cm to 60 cm was the lowest. The research conclusion had provided basic data and resources for fiver basin water balance and water conservation function, the adjusting and management stand structure and utilization water resources and studying soil water.