粤西桉树人工林土壤水分空间异质性分析

Spatial Analysis of Soil Moisture in Eucalyptus Plantations in West Guangdong

依据2 hm2样方的调查数据,结合经典统计学与地统计学方法对广东省肇庆市三叉顶自然保护区桉树人工林土壤水分的空间异质性进行了研究.结果表明,随着林龄的增长,土壤水分含量有增加的趋势;不同林龄桉树林不同土层水分含量差异明显（p〈0.05）.1年生桉树林0－25,25－50 cm层土壤水分变异函数的最佳拟合模型均为指数模型,3年生桉树林各层土壤水分变异函数的最佳拟合模型均为球状模型.空间自相关分析表明,同林龄桉树林各层土壤水分均具有强烈的空间自相关性,且自相关部分的空间变异性在总的空间变异性中占主要部分.同林龄桉树林在不同土层土壤水分具有相似的空间自相关变化趋势,不同林龄桉树林相同土层土壤水分的空间自相关变化趋势差异明显.Kriging插值分析显示,1年生桉树林各层土壤水分空间变异性小,空间依赖性小,破碎化程度相对较高.3年生桉树林各层土壤水分空间变异性大,空间依赖性相对较高,破碎化程度较低.

Based on 2 hm2 sample plots,soil moisture spatial characteristics is investigated in the Eucalyptus plantations in West Guangdong.The results show that mf the total carbon storageysteme environmental factors.nd krigingies analysis（ISA）nalyses including analysis of variance（the difference of soil moisture content in eucalyptus forest is significant（P〈0.05）.Geostatistics analyzes indicated that soil moisture content in 3 years stand was best fitted by the exponential model;whereas soil moisture content in 1 year stand was best fitted by the spherical model.Soil moisture in each soil layer of two stands all exhibited similar spatial structures with strong strength.A kriging map for the soil moisture in each of the soil layer in different stand showed in details smaller spatial heterogeneity and interdependance and higher fragmentation for the 0～25 cm and 25～50 cm soil layers in 1 year stand,and similar spatial variabilty and interdependance and lower fragmentation for the 0～25 cm and 25～50 cm in 3 years stand.