黑河流域中部土壤微量元素有效态含量的空间变异及丰缺评价

基于G IS技术,通过地统计学方法对张掖临泽、山丹、民乐县和甘州区农田表层土壤有效Fe、Cu、Zn、Mn、N i和Co含量的空间变异、丰缺状况及影响因素进行了研究。结果表明:有效Fe含量的最适模型为球状模型,Cu、Zn和N i为指数模型,Mn和Co为高斯模型;有效N i和Mn具有强烈空间相关性,有效Fe、Cu、Zn和Co具有中等空间相关性;各微量元素有效态含量均具有各向异性。研究区域有效Fe、Cu、Zn和N i含量在甘州区最高,有效Mn和Co含量由东南到西北逐渐减小;有效Cu和N i含量大部分面积处于中等及丰富水平,而有效Fe、Zn和Mn含量为中等及偏低水平。土壤有机质与六种微量元素有效态含量均呈显著或极显著正相关;pH与有效Fe、Cu、Zn和N i含量呈显著或极显著负相关。

Spatial variability and abundance evaluation of available microelements in the middle reaches of Heihe River

Geostatistics combined with GIS was applied to study the spatial variability,level status and influencing factors of available Fe,Cu,Zn,Mn,Ni and Co in soils in the Linze,Shandan,Minle County and Ganzhou of Zhangye city.The results showed that better theoretical semivariogram models of available microelements were spherical model for Fe,exponential model for Cu,Zn and Ni,and Gaussian model for Mn and Co.Available Ni and Mn had a strong spatial correlation,indicating that their contents were affected by structural factors.The content of available Fe,Cu,Zn and Co had a moderate spatial correlation,indicating that their contents were affected by structural factors and random factors.All available trace elements expressed anisotropy.By kriging interpolation,the contents of available Fe,Cu,Zn and Ni were the hightest in Ganzhou district,the distribution of Mn and Co presented continous zonal distribution obviously,and the decreasing trend was found from southeast to northwest.The contents of available Cu and Ni were moderate or rich,while the contents of available Fe,Zn and Mn were moderate or low in the soils.The soil organic matter had a significant positive correlation with six available microelements,and pH had a significant negative correlation with available Fe,Cu,Zn,and Ni.