浑太河流域氮磷空间异质性及其对土地利用结构的响应

利用2009年8月和2010年6月浑太河流域河流水体采样数据,结合GIS技术和地统计学方法,分析了汛期TN(总氮)、NH4+-N(氨氮)、NO3--N(硝酸盐氮)、TP(总磷)和PO43-(磷酸盐)在地表水体中的空间变异特征,并探讨了流域尺度上土地利用对氮磷营养物质的影响.结果表明:NH4+-N、PO43-和TN均受到结构性因素的影响,表现出一定空间相关性变异特征;NO3--N和TP主要受到随机性因素的影响,表现出极弱的空间相关性变异特征.汛期流域林地、农田和居民用地比例与氮素呈显著相关,农田和草地用地比例与氮磷均呈显著相关.可以初步推测,林地、农田和居民用地是控制氮素空间分异特征的结构性因素,农田和草地是控制磷素空间分异特征的结构性因素.

Spatial Variability Analysis of Water Nitrogen and Phosphorus and Their Response to Land-Use Structures in the Huntai River Basin

Water samples were collected in the Huntai River basin in August 2009 and June 2010, and the spatial variabilities of TN, ammonia-nitrogen, nitrate, TP and phosphate during flood season were analyzed by using GIS technique and geostatistics method. The influence of land use on nitrogen and phosphorus distribution was analyzed at sub-basin scales. The results indicated that distributions of TN, ammonia-nitrogen and phosphate had a certain spatial-related variability which were influenced by certain structural factors; and, distributions of nitrate and TP had a very weak spatial-related variability which may be affected by random factors. The results of the analysis of the influence of land use on TN, ammonia-nitrogen, nitrate, TP and phosphate indicated that the structure of land use had important influence on these parameters. Percentage of forested land, cultivated land and settlement land were significantly correlated with nitrogen, while percentage of grassland and cultivated land were both significantly correlated with nitrogen and phosphorus. The results concluded that forest, farmland and settlements are structural factors to nitrogen, while farmland and grassland are the structural factor to phosphorus.