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青藏高原高寒草原区,由于长期冻融和地下冰的存在形成了独特的生态水文结构,土壤水分是控制高寒草原生态过程的关键因子。利用地统计学对多年冻土区高寒草原土壤表层含水量和植被盖度的空间变异性进行研究,结果表明,高寒草原生态系统浅层剖面(0~50 cm)土壤水分和植被盖度均符合正态分布,土壤含水量沿垂直方向逐渐增大,介于19.43%~25.37%之间,变异系数介于23.77%~40.92%;植被盖度具有强变异性,变异系数为47.99%。0~50 cm土壤含水量具有高度的空间异质性,其中91.1%的空间异质性是由空间自相关部分引起的,主要体现在10~190 m的中尺度上;植被盖度在研究尺度上具有中等程度的空间自相关,植被盖度随机部分的空间变异性占总空间变异性的比例为34.2%,主要体现在<10 m的尺度内。各向异性分析表明,土壤水分和植被盖度具有明显的各向异性,其空间格局有明显的差异。
The alpine steppe area of the Qinghai-Tibet Plateau forms a unique eco-hydrological structure due to the long-term freeze-thaw and underground ice. Soil moisture is the key factor controlling the ecological process in the alpine steppe. The spatial variability of surface soil moisture and vegetation coverage of alpine steppe in permafrost regions was studied using geostatistics. The results showed that the soil moisture and vegetation coverage in shallow section (0 ~ 50 cm) Normal distribution, soil moisture content along the vertical direction gradually increased, ranging from 19.43% to 25.37%, the coefficient of variation ranged from 23.77% to 40.92%; vegetation cover has strong variability, the coefficient of variation was 47.99%. The spatial heterogeneity of soil water content in 0 ~ 50 cm depth was high, of which 91.1% spatial heterogeneity was caused by spatial autocorrelation, which mainly reflected in the mesoscale 10 ~ 190 m. The vegetation coverage in the study scale Had a moderate degree of spatial autocorrelation. The spatial variability of random parts of vegetation cover accounted for 34.2% of the total spatial variability, mainly in the scale of <10 m. Anisotropy analysis shows that soil moisture and vegetation coverage have obvious anisotropy, and the spatial pattern has obvious difference.