不同尺度下低山茶园土壤阳离子交换量空间变异性研究

Study on the Spatial Variability of the Soil Cation Exchange Capacity in Hilly Tea Plantation Soils with Different Sampling Scales

【目的】研究茶园土壤阳离子交换量(CEC)的空间变异性特征,可以为茶园生态建设以及茶园土壤肥力管理提供理论依据。【方法】本文利用地统计学方法探讨了两个取样尺度下四川蒙顶山茶园土壤CEC的空间变异性特征。【结果】(1)小尺度下,茶园土壤CEC具有强烈的空间相关性(C0/(C0+C)值为18.84%),相关距离高达1818m,结构性因子是影响其空间变异的主要因素;(2)微尺度下,茶园土壤CEC仍具有强烈的空间相关性(C0/(C0+C)值为16.52%),空间相关距离达311m,结构性因子是影响其空间变异的主要因素。【结论】小尺度下土壤CEC在坡度方向变异明显,横坡方向变异最弱;普通Kriging插值分析表明其在东北至西南方向呈明显的条带状分布,并在垂直方向随海拔高度的上升而增加;微尺度下土壤CEC的变异方向与小尺度下不同,在接近坡度的方向空间变异明显,接近横坡方向变异最弱;土壤CEC沿横坡方向呈条带状分布并伴随部分斑块状分布,从坡面至上而下,呈先增加后减少再增加的趋势。

【Objective】Studies about the spatial variability of the soil cation exchange capacity（CEC）could provide a theoretical basis for the construction of ecological tea plantation and management of soil fertilizer in tea plantation.【Method】 Geostatistics were used for the analysis of the spatial variability of soil CEC in tea plantation in Mengding mountain in Sichuan province with two sampling scales.【Result】（1）In the tea plantation at small scale,the soil CEC was strongly and spatially dependent,the rate of nugget to sill was 18.84%,the range of spatially dependent was 1 818 m.Structural factors were the main factors which affected the spatial variability of the soil CEC.（2）In the tea plantation at micro scale,the soil CEC was strongly and spatially dependent,too,and the rate of nugget to sill was 16.52%,the range of spatially dependent was 311 m.Structural factors were the main factors which affected the spatial variability of the soil CEC.【Conclusion】In the tea plantation at small scale,the soil CEC had a stronger anisotropic structure in the aspect of the slope,and a weaker one at the aclinic aspect of the slope.According to the Ordinary Kriging method,the equivalence of the soil CEC was distributed along the aclinic aspect of the slope from northeast to southwest,and the soil CEC content was reduced as the elevation went down.In the tea plantation at micro scale,the anisotropic Structure was different with a small scale,it had a stronger anisotropic structure in the aspect which near the aspect of slope,and a weaker one near the aclinic aspect of the slope.The soil CEC distributed along the aclinic aspect of the slope and some distributed like spots.From top to down of the slope,the soil CEC increased first,then reduced,and finally increased.