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土壤中的磷是衡量土壤肥力的重要指标,其含量的高低对土壤理化性质、植物生长以及微生物的活动等都有重要影响.本文以周口黄泛区土壤为例,通过土样采集和室内试验分析,运用地统计分析及GIS空间模拟等方法,分析土壤全磷和速效磷的空间分布特征.结果表明:研究区土壤全磷和速效磷含量比较高,且表层(0~20 cm)含量均高于第二层含量(20~40 cm).两层土壤全磷和速效磷均属于中等程度变异,并且速效磷的变异程度高于全磷;两层土壤全磷为中等程度的各向异性,最适模型为高斯模型,表层具有较强的空间相关性,第二层则具有中等的空间相关性.两层土壤速效磷的各向异性均较弱,最适模型为线性模型,两层均呈现较弱的空间相关性.两层全磷含量从西南到东北方向呈现缓慢上升的变异趋势,而从西北到东南方向呈逐渐下降的变异趋势.表层速效磷含量在西南到东北方向先升后降,在东南到西北方向呈先降后升的变异趋势;第二层速效磷含量在西南到东北方向上呈现先降后升的趋势,而在西北到东南方向则呈上升趋势.表层土壤全磷含量较高,第二层含量属于中等水平;表层速效磷含量较高,而第二层含量较低.土地利用方式、耕作制度和施肥等人为因素是影响该区土壤磷分布趋势和空间变异的主要因素.
Soil phosphorus is an important indicator of soil fertility, and its content has an important impact on soil physical and chemical properties, plant growth and microbial activity, etc. In this paper, The spatial distribution characteristics of total phosphorus and available phosphorus in soil were analyzed by means of geostatistical analysis and GIS spatial simulation.The results showed that the contents of total phosphorus and available phosphorus in soil were relatively high and the contents of surface layer (0-20 cm) Higher than that of the second layer (20-40 cm). The total phosphorus and available phosphorus in the two soil layers all belonged to a moderate degree of variation, and the variation of available phosphorus was higher than that of total phosphorus. The total phosphorus in the two layers was moderately anisotropic , The optimum model is Gaussian model, the surface has strong spatial correlation, the second layer has a moderate spatial correlation.The two layers of soil available phosphorus anisotropy weaker, the optimal model for the linear model, two layers Showed a weaker spatial correlation.The total P content in the two layers showed a slowly increasing trend from southwest to northeast and a decreasing trend from northwest to southeast.The content of available phosphorus in the surface layer ranged from southwest to northeast The content of available phosphorus in the second layer showed the trend of first decreasing and then increasing in the southwest to the northeast and rising in the northwest to the southeast. The content of total phosphorus in the surface soil was higher, the content of the second layer was middle level, the content of available phosphorus in the surface was higher and the content of the second layer was lower.The human factors such as land use, farming system and fertilization were the trend of soil phosphorus distribution And the main factor of spatial variation.