呼伦贝尔道路对草地土壤表层颗粒组成空间变异的影响

[目的]揭示呼伦贝尔草地不同道路影响下路边土壤表层颗粒组成的空间变异特征,为道路沿线水土流失治理提供科学依据。[方法]对省道S203和土路的坡顶、坡底、轮坑以及0—30 m样带和30—210m样带进行实地采样,经风干处理后用吸管法测定了颗粒组成,采用ArcGIS 10.0软件进行的克里金插值和半方差分析。[结果]省道S203,路边土壤粉粒和石砾含量空间变异较大,变异系数分别为95.96%和80.05%。道路边坡附近粉粒和黏粒含量少,随着与路边距离的增加,粉粒和黏粒含量增加;而土路对路边土壤黏粒含量的影响较大,车轮碾压轮坑附近黏粒含量多;道路和沿线人类活动对石砾和粉粒含量的影响强至中等。[结论]受人类活动影响,研究区道路沿线土壤表层不同颗粒组成空间分布发生变化,而黏粒含量形成了沿着道路呈带状分布的空间分布特征。

Influences of Roads on Spatial Variance of Top Soil Particle Size Distribution of Hulunbeier Grassland

[Objective] Studying the influences of different roads on spatial variance of top soils particle size distribution of Hulunbeier grassland to provide basis for soil erosion control. [Methods] Roadside top soil(1-10 cm) samples were collected at the top and bottom of road bank, the wheel rolling pit, the 0-30 m belts, and the 30-210 m belts from provincial road S203 and unsurfaced road. The soil samples were air dried and then the particle size distribution was measured by pipette method. All data were analyzed by GIS based techniques including Kriging interpolation and semivariance analysis. [Results] There was a significant spatial variance for silt and gravel in the provincial road S203; the coefficients of variation were 95.96% and 80.05%, respectively. Near the road bank, the soils'' contents of silt and clay were smaller than other sampling sites, but gravel contents were lager than others. The larger of distance between sampling sites and road, the greater of contents of silt and clay. The soil contents of clay and silt near the wheel rolling pits were lager than other sampling sites for the unsurfaced road. The influences of roads on the contents of silt and gravel in roadside top soil were between strongly to moderately. [Conclusion] Affected by human activities, the particle size distribution patterns of top soils in studying area were reformed, and the contents of clay showed a zonal distribution patterns along the roadsides.