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土壤水分含量是荒漠植被发育的主要制约因子。对古尔班通古特沙漠南缘个体、群落、丘间地0~100cm干季土壤水分含量的空间异质性进行分析。结果表明:(1)同尺度下,土壤水分含量随土层深度增加呈显著升高趋势,且表层土壤水分含量的变异系数高于其他土层。(2)个体尺度,梭梭树干基部周围土壤水分含量在垂直和水平方向存在格局分异。垂直方向,土壤水分含量随土层深度增加呈升高趋势。水平方向,随距树干基部距离增加,坡顶土壤水分含量呈升高趋势,坡中和坡底土壤水分含量呈降低趋势,但没有显著差异。(3)梭梭群落尺度上土壤水分含量异质性较强,且呈斑块状分布。(4)地形是影响丘间地尺度土壤水分含量空间分异的主要因素,形成坡底土壤水分含量最高、坡中次之、坡顶最低的空间分布格局。
Soil moisture content is a major constraint on the development of desert vegetation. Spatial heterogeneity of soil water content in 0-100 cm dry season in individuals, communities and mound in the southern edge of the Gurbantunggut desert was analyzed. The results showed that: (1) Under the same scale, the soil moisture content increased significantly with the depth of soil layer, and the coefficient of variation of surface soil moisture content was higher than other soil layers. (2) At the individual scale, soil water content around the base of Haloxylon ammodendron varied in different vertical and horizontal directions. In the vertical direction, soil moisture content increased with soil depth increasing. In the horizontal direction, the soil water content at the top of the hillside increased with increasing distance from the base of the trunk, and the soil water content in the middle slope and bottom of the hillside showed a decreasing trend, but there was no significant difference. (3) The soil moisture content of Haloxylon ammodendron was highly heterogeneous and patchy. (4) The topography is the main factor that affects the spatial heterogeneity of soil water content at the inter-mound scale, and forms the spatial distribution pattern with the highest soil moisture content at the bottom of the slope, the second highest in the slope, and the lowest slope top.