多尺度环境因子对广州市流溪河河岸带土壤理化性质空间分异的影响

Effects of multi-scale environmental factors on spatial heterogeneity of soil physical and chemical properties of riparian zone in Liuxi River of Guangzhou

以广州市水源地流溪河二级支流的河岸带为研究对象,分析流域多尺度环境因子对河岸带土壤理化性质的影响,确定调控河岸带土壤理化性质的不同尺度景观因子,为河岸带管理和修复提供科学依据。结果表明,河岸带流域纵向尺度上的地形指数、坡度、海拔、土地利用类型等因子是影响土壤水分含量、土壤质地及p H的主要因素;河岸带横向断面尺度上距河边远近不同的景观位置及植被覆盖度因子是影响土壤可溶性有机碳、土壤硝态氮及土壤容重的主要因素;河岸带垂直剖面尺度上人为活动对土壤干扰强度大小、剖面根系分布情况及地下水位高低是影响土壤有机碳、总氮及铵态氮的主要因素。

The effects of multiscale catchment landscape features on soil physical and chemical properties of riparian zone along the secondorder tributaries of Liuxi River in Guangzhou City were analyzed. The objective of this study was to explore and identify the main factors that influence soil properties at different spatial scales and to provide scientific data for riparian zone management and restoration. The results showed that along the longitudinal direction of the riparian zone, topographic index, land slope, land elevation and landuse type were the governing factors on the spatial heterogeneity of soil water content, soil textures and pH. Along the transversal direction, the distance of a landscape from riverside and the vegetation coverage were the main factors affecting the spatial heterogeneity of soil dissolved organic carbon, nitrate nitrogen （NO3^--N） and bulk density. Along the vertical profile of the riparian zone, the intensity of human disturbance on soil, the root system distribution in soil profile and the groundwater tables were the major factors affecting the spatial heterogeneity of soil organic carbon, TN and NH4^＋-N in the riparian zone.