喀斯特木论自然保护区旱季土壤水分的空间异质性

采用经典统计学和地统计学方法，分段研究了喀斯特木论自然保护区典型峰丛坡地和洼地旱季表层土壤水分（0～5 cm和5～10 cm）的空间异质性.结果表明：研究区旱季表层土壤水分仍然较高，总体上具有良好的半方差结构;坡地和洼地0～5 cm和5～10 cm土层土壤水分的空间分布均符合指数模型，同一立地条件下两土层土壤含水量具有相似的空间结构和分布格局，相同土层不同立地条件下的差异明显;坡地土壤水分含量的空间相关性中等且连续性好，具有明显的斑块分布格局，其Moran I值的变化相对缓慢;洼地土壤水分含量具有强烈的空间自相关，但变程很短，其Moran I值的波动较大，斑块比较破碎.地形、微地貌、降雨、人为干扰特别是植被是保护区土壤含水量空间变异的重要影响因素，保存完好的原始森林对土壤水分空间异质性具有良好的调控作用.

Spatial heterogeneity of surface soil moisture content in dry season in Mulun National Natural Reserve in Karst area.

By the methods of classical statistics and geostatistics, the spatial heterogene ity of surface soil (0〖KG-*2〗-〖KG-*7〗5 cm and 5〖KG-*2〗-〖KG-*7〗10 cm laye rs) moisture content in dry season in the typical sloping fields and depressions in Mulun National Natural Reserve in Karst area were studied. The results indic ated that in study area, the surface soil moisture content in dry season was sti ll higher, and showed a fine semivariogram structure as a whole. The spatial distribution of moisture cont ent in 0〖KG-*2〗-〖KG-*7〗5 cm and 5〖KG-*2〗-〖KG-*7〗10 cm soil layers, both for sloping fields and for depressio ns, fitted exponential model well. Under the same stand conditions, the moisture content in the two soil layers had the similar spatial structure and distributi on pattern; while under different stand conditions, there existed obvious differ ence in the same soil layer. The spatial pattern of surface soil moisture conten t in sloping fields was characterized by medium spatial autocorrelation, clear p atches with well continuum, relatively slow variation of Moran’s I index, while that in depressions was characterized by strong spatial autocorrelation, larger variation of Moran’s I index, and more fragmented patches. Therefore, topograp hy, micro-physiognomy, precipitation, human disturbance, and especially vegetat ion were the most important factors affecting the spatial pattern of soil moistu re content in the Mulun National Natural Reserve, and to preserve primary forest should have favorable effect on the regulation of the spatial heterogeneity of soil moisture content in the Reserve.