论文部分内容阅读
采用地理信息系统(GIS)和地统计学方法,研究了太湖流域宜兴地区不同土地利用方式下土壤氮、磷的空间变异特性。结果表明,研究区土壤全氮、速效磷含量均处于I级水平,不同利用方式的土壤全氮变异系数在30%左右,速效磷处于25%~65%间,空间分布不均匀。与1982年监测结果相比,土壤全氮、速效磷含量均得到提高,其中速效磷含量提高226%,增幅十分显著。水稻田的全氮含量、菜园土的速效磷含量均显著高于其他土壤,达到极显著水平。菜园土全氮和速效磷半方差函数模型的块基比分别为44.87%和58.82%,空间相关性最弱,而人工管理措施最少的果园土其空间相关性最强,块基比分别为26.45%和21.88%。宜兴地区土壤氮磷含量分布不均,与种植制度、肥料施用量等农业管理措施有关。土壤全氮、速效磷含量分布特性与其利用方式关系密切,不同利用方式下土壤的空间相关性有明显差异。宜兴境内太湖沿岸区域土壤氮磷含量过高,需要控制肥料的施加量,提高利用率,减少农业面源污染。
Using GIS and geostatistics methods, the spatial variability of soil nitrogen and phosphorus under different land use patterns in Yixing, Taihu Lake region was studied. The results showed that the contents of total nitrogen and available phosphorus in soil were all at level I. The coefficient of variation of soil total nitrogen was about 30% and the available phosphorus was between 25% and 65% under different utilization patterns. The spatial distribution was not uniform. Compared with the monitoring result in 1982, the content of soil total nitrogen and available phosphorus increased, and the content of available phosphorus increased by 226%, showing a significant increase. Total nitrogen content in paddy soils and available phosphorus in vegetable soils were significantly higher than those in other soils, reaching extremely significant levels. The vegetable-soil total nitrogen and available phosphorus semi-variance function model of the block basis ratio were 44.87% and 58.82%, the spatial correlation is the weakest, while the man-made orchard with the least man-made management measures the spatial correlation of strongest, block base ratio was 26.45 % And 21.88%. The distribution of nitrogen and phosphorus in soil in Yixing is uneven, which is related to agricultural management measures such as cropping system and fertilizer application. Soil nitrogen content and available phosphorus content were closely related to their utilization patterns. There were significant differences in soil spatial correlation under different utilization patterns. The content of nitrogen and phosphorus in soils along Taihu Lake coast in Yixing is too high, so it is necessary to control the amount of fertilizer applied, increase the utilization rate and reduce agricultural non-point source pollution.