西昌市耕地土壤有效钼空间变异特征及影响因素分析

采用GIS和地统计相结合的方法,对西昌市耕地土壤耕层有效钼含量的空间分布特征及影响因素进行分析.结果表明:该区域内耕层土壤有效钼含量为( 0.27±0.15 )mg/kg,其空间分布呈带状,土壤有效钼含量变异函数曲线的理论模型能较好地符合指数模型;块金值与基台值之比为6.1％,具有强烈的空间相关性,表明受母质、地形、土壤类型等结构性因素影响较大；不同海拔高度对土壤有效钼含量的影响存在显著差异;不同地貌类型中土壤有效钼含量为平原＞丘陵＞山地,平原与山地之间土壤有效钼含量存在显著差异,但平原与丘陵、丘陵与山地之间无显著差异;成土母质也是影响土壤有效钼空间分布的主要因素.

Analysis on Spatial Variability and Affecting Factors of Available Molybdenum in Cultivated Soil of Xichang City

The spatial distribution characteristics of available molybdenum content in topsoil soil sampled from Xichang city were analyzed using Geostatisitics and GIS methods,as well as factors affecting available molybdenum content.The results showed that the content of available molybdenum in the studied region was(0.27±0.15)mg / kg;and spatial distribution of available molybdenum was belt-shaped.The theoretical mode of variogram curve of available molybdenum fitted the exponential model.The ratio of nugget and sill was 6.1% which had a strong spatial correlation.It showed that available molybdenum was strongly influenced by the structural factors such as parent material,topography,soil type and so on.The content of available molybdenum had significant difference between different altitudes.The order of available molybdenum content was plain> hills> mountain;and there was significant different between plain and mountain.Soil parent material was one of the main factors influencing the spatial distribution patterns of available molybdenum.