State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, China.
Int J Environ Res Public Health. 2011 Aug;8(8):3299-317. doi: 10.3390/ijerph8083299. Epub 2011 Aug 15.
The study presented in this paper attempts to evaluate the spatial pattern of soil available phosphorus, as well as the relation between soil available phosphorus and environment factors including elevation, slope, precipitation, percentage of cultivated land, percentage of forest land, percentage of construction land and NDVI using statistical methods and GIS spatial analysis techniques. The results showed that the Spline Tension method performed the best in the prediction of soil available phosphorus in the Chaohu Lake watershed. The spatial variation of surface soil available phosphorus was high in Chaohu Lake watershed and the upstream regions around Chaohu Lake, including the west of Chaohu lake (e.g., southwest of Feixi county, east of Shucheng county and north of Lujiang county) and to the north of Chaohu Lake (e.g., south of Hefei city, south of Feidong county, southwest of Juchao district), had the highest soil available phosphorus content. The mean and standard deviation of soil available phosphorus content gradually decreased as the elevation or slope increased. The cultivated land comprised 60.11% of the watershed and of that land 65.63% belonged to the medium to very high SAP level classes, and it played a major role in SAP availability within the watershed and a potential source of phosphorus to Chaohu Lake resulting in eutrophication. Among the land use types, paddy fields have some of the highest maximum values and variation of coefficients. Subwatershed scale soil available phosphorus was significantly affected by elevation, slope, precipitation, percentage of cultivated land and percentage of forest land and was decided by not only these environmental factors but also some other factors such as artificial phosphorus fertilizer application.
本文旨在运用统计方法和 GIS 空间分析技术，评估土壤有效磷的空间分布格局以及土壤有效磷与包括海拔、坡度、降水、耕地比例、林地比例、建设用地比例和 NDVI 等环境因子之间的关系。结果表明，样条张力法在预测巢湖流域土壤有效磷方面表现最佳。巢湖流域及其上游地区（如肥西县西南、舒城县东部和庐江县北部）和巢湖北部（如合肥市南部、肥东县南部、居巢区西南部）表层土壤有效磷空间变异性较大，土壤有效磷含量较高。随着海拔或坡度的增加，土壤有效磷含量的平均值和标准差逐渐降低。耕地占流域面积的 60.11%，其中 65.63%属于中到高 SAP 水平类，在流域内 SAP 有效性方面发挥着重要作用，也是导致巢湖富营养化的潜在磷源。在土地利用类型中，稻田的最大值和变异系数较高。子流域尺度的土壤有效磷受海拔、坡度、降水、耕地比例和林地比例的显著影响，不仅受这些环境因子的影响，还受人为施磷等其他因子的影响。
