基于地统计学及GIS的西昌地区中生代红层区紫色土营养元素空间变异性及影响因素研究

Study on Spatial Variability and Influencing Factors of Nutrient Elements in Purple Soil in Mesozoic Red Layer Region in Xichang Area Based on Geostatistics and GIS

基于大凉山生态地质调查获取的48个岩石—土壤剖面数据,通过地质建造单元调查、土壤类型划分及元素地球化学测试,采用地统计学方法和GIS技术对西昌地区中生代泥质岩类地质建造区紫色土中4种微量营养元素Cu、Zn、Mo和B的空间变异及分布特征展开研究,并讨论了不同影响因素下4种营养元素的含量特征。结果表明:①4种营养元素整体属于中等强度变异,高斯模型和指数模型可以很好地反映研究区4种营养元素的空间变异特征;②4种营养元素整体处于丰富等级,Cu、Zn和B营养元素含量高值区主要集中分布在西昌地区东北—西南带状区域内,Mo元素含量在全区范围内含量较高;③不同地质条件(海拔高度、地层、岩性、地质时代)和不同植被覆盖类型共同制约着Cu、Zn、Mo和B植物生长所需的营养元素含量及空间分布特征。此外,紫色土剖面土壤层4种营养元素的含量特征还受到一定的人类活动影响。研究结果可以对当地农林业发展及土地资源的合理利用提供一定参考。

Based on the data of 48 rock-soil profiles obtained from the ecological,geological survey of Daliang Mountain,the geological formation unit survey,soil type division,and geochemical element test,the spatial variation and distribution characteristics of four micronutrient elements,Cu,Zn,Mo,and B,in purple soil in a Mesozoic argillaceous rock geological formation zone in Xichang area were studied by geostatistics and GIS technology,The content characteristics of four nutrient elements under different influencing factors were discussed.The results show that①the four nutrient elements belong to medium intensity variation,and the Gaussian and exponential models can accurately reflect the spatial variation characteristics of the four nutrient elements in the study area;②the four nutrient elements are at a rich level.The high-value areas of Cu,Zn,and B nutrient elements are mainly distributed in the northeast—southwest belt zone of the study area;the Mo content is high in the whole area;③different geological conditions(altitude,stratum,lithology,and geological age)and vegetation cover types jointly restrict the content and spatial distribution characteristics of nutrient elements required for the growth of Cu,Zn,Mo,and B plants.In addition,the content characteristics of the four nutrient elements in the soil layer of the purple soil profile were also affected by human activities.These results can provide a reference for developing local agriculture and forestry and the rational utilization of land resources.