湖北省两种地形区耕地土壤肥力指标空间格局与主控因素

Spatial Patterns and Main Control Factors of Soil Fertility Indicators in Arable Land in Two Topographic Regions of Hubei Province

[目的]研究湖北省2种地形的土壤肥力指标分异空间格局及主控因素差异,为不同地形区土壤质量改良,农业生态环境及耕地质量提升提供一定理论依据。[方法]选取土壤有机质、全氮、全磷、全钾4种土壤肥力指标,并收集整理土地利用类型、成土母质、土壤类型、高程(DEM)、地表起伏度、坡度、植被覆盖度指数(NDVI)、平均气温、平均降水量以及道路、工矿用地、城镇居民点、河流水库13种环境影响因子,利用基本统计学、地统计学、反距离权重和地理探测器模型,分析不同地形区每种土壤肥力指标的空间分布特征以及每种土壤肥力指标与环境因子之间的相关性,并识别对比不同地形区土壤肥力指标含量分异的主控因子。[结果]襄州区土壤肥力指标主控因素主要有降水量、平均气温,以及道路用地、城镇居民点用地、工矿用地、河流水库距离;房县土壤肥力指标主控因素主要有降水量、平均气温、坡度、坡向、地表起伏度以及河流水库距离。[结论]襄州区与房县因地形因素影响其土壤肥力指标空间格局分异主控因素存在差异,平原区更易受人类活动影响。

[Objective]The spatial pattern of a soil fertility index and differences in the main controlling factors for two topographical areas in Hubei Province was determined in order to provide a theoretical basis for soil quality improvement,agroecological environment,and arable land quality enhancement in different topographical areas.[Methods]Data for four soil fertility indicators(soil organic matter,total nitrogen,total phosphorus,and total potassium),along with 13 environmental impact factors〔land use type,soil-forming parent material,soil type,elevation(DEM),surface relief,slope,normalized difference vegetation index(NDVI),average temperature,average precipitation,roads,industrial and mining sites,urban settlements,and rivers and reservoirs〕,were collected and compiled.Basic statistics,geostatistics,inverse distance weighting,and a geographic detector model were used to analyze the spatial distribution characteristics of each soil fertility index in different topographic areas and to determine the correlation between each soil fertility index and environmental factors.The main controlling factors of the soil fertility index content differentiation in different topographic areas were identified and compared.[Results]The main controlling factors for the soil fertility indexes in Xiangzhou District were precipitation,average temperature,and the distance of road land,urban settlement land,industrial and mining land,and rivers and reservoirs.The main controlling factors for soil fertility indexes in Fang County were precipitation,average temperature,slope,slope direction,surface relief,and the distance of rivers and reservoirs.[Conclusion]The spatial patterns of soil fertility indicators in Xiangzhou District and Fang County differed in their main controlling factors due to topographic factors,and the plain areas were more susceptible to human activities.