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通过网格(5 m×5 m)取样,用地统计学方法研究了喀斯特峰丛洼地4个典型植被类型表层土壤(0～10 cm)水分的空间导质特征,探讨了其生态学过程和机制。结果表明,随着干扰强度的降低,植被产生了由农作物(Ⅰ)→人工林(Ⅱ)→次生林(Ⅲ)→原生林(Ⅳ)的变化,土壤水分显著提高,空间变导特征明显不同,Ⅰ、Ⅱ、Ⅲ和Ⅳ分别符合指数模型、高斯模型、指数模型和球状模型,块金值与基台值之比(C_0/(C_0+C))在0.269～0.500之间,具有中等的空间相关性,Ⅰ和Ⅳ土壤水分的空间结构相似,(C_0/(C_0+C))值较大,随机因素和自相关异质性各占50%,分维数D值较大,空间依赖性较小,Ⅱ和Ⅳ相反;农业耕作区土壤水分的空间延续范围较大,变程达252.9 m,其他3个植被类型的变程均较小(141.2～163.2 m);Kriging等值线图从不同位置和方向上清楚地表明Ⅰ和Ⅳ土壤水分的空间分布均呈凸型分布,Ⅱ呈单峰分布,Ⅲ呈凹型分布;影响土壤水分空间分布的因子很多,其中干扰通过对植被的调控发挥了关键作用,降低干扰是喀斯特峰丛洼地脆弱生态系统水资源改善、合理利用及生态恢复重建的重要举措。
Through the grid (5 m × 5 m) sampling, the spatial characteristics of water content in the topsoil (0 ~ 10 cm) of four typical vegetation types in the karst peak cluster depression were studied by geostatistics method, and the ecological process and mechanism were discussed . The results showed that with the decrease of disturbance intensity, the vegetation changed from crop (Ⅰ) → plantation (Ⅱ) → secondary forest (Ⅲ) → primary forest (Ⅳ), the soil moisture increased obviously and the spatial variability was obviously different. Ⅰ, Ⅱ, Ⅲ and Ⅳ are in accordance with the exponential model, the Gaussian model, the exponential model and the spherical model respectively. The ratio of the gold value to the base station value (C_0 / (C_0 + C)) is between 0.269 and 0.500, (C_0 / (C_0 + C)), the stochastic and autocorrelation heterogeneity accounted for 50%, the fractal dimension D was large and the spatial dependence And the opposite of Ⅱ and Ⅳ. The spatial extent of soil moisture in agricultural cultivation area is larger, with a variation range of 252.9 m and a smaller variation of the other three vegetation types (141.2 to 163.2 m). Kriging contour map from The different locations and orientations clearly show that the spatial distributions of soil water in Ⅰ and Ⅳ are all convex distribution, the distribution of Ⅱ is single peak, and the distribution of Ⅲ is concave. There are many factors influencing the spatial distribution of soil moisture, of which interference plays a role in the regulation of vegetation A key role in reducing disturbance is the improvement of water resources in fragile ecosystems of karst peaks and valleys Rational utilization and ecological restoration and reconstruction of important initiatives.