地理研究 ›› 2004, Vol. 23 ›› Issue (1): 63-70.doi: 10.11821/yj2004010008

• 论文 • 上一篇    下一篇

太湖流域典型地区土壤全氮的空间变异特征

刘付程1,2, 史学正1, 于东升1, 潘贤章1   

  1. 1. 中国科学院南京土壤研究所,江苏南京210008;
    2. 安徽师范大学,安徽芜湖241000
  • 收稿日期:2003-03-03 修回日期:2003-07-26 出版日期:2004-02-15 发布日期:2004-02-15
  • 作者简介:刘付程(1971-),男,安徽枞阳县人,讲师,博士研究生。主要从事土壤资源管理研究。
  • 基金资助:

    国家重点基础研究规划项目(G1999011810);中国科学院知识创新工程重大项目(KZCX1SW0119)资助

Characteristics of spatial variability of total soil nitrogen in the typical area of Taihu Lake basin

LIU Fu-cheng1,2, SHI Xue-zheng1, YU Dong-sheng1, PAN Xian-zhang1   

  1. 1. Institute of Soil Science, CAS,Nanjing 210008, China;
    2. Anhui Normal University,Wuhu 241000, China
  • Received:2003-03-03 Revised:2003-07-26 Online:2004-02-15 Published:2004-02-15

摘要:

在地理信息系统的支持下 ,运用地统计学方法分析了太湖流域典型地区耕层土壤全氮的空间变异特征 ,并在此基础上利用BlockKriging法绘制了土壤全氮的空间分布图。结果表明 ,研究区域土壤全氮具有明显的空间自相关性 ,自相关距离在 16km左右。在 4 0km步长变化范围内 ,土壤全氮的空间变异表现为明显的各向同性特征 ,超出此范围 ,各向异性趋向明显。Kriging插值结果表明 ,土壤全氮含量在江阴和宜兴境内要高于锡山和武进境内 ,且高值斑块区主要分布在地势低洼的圩田区。

关键词: 土壤全氮, 地统计学, 空间变异, Kriging

Abstract:

Nonpoint sources of nitrogen (N) in agricultural soils have been identified as one of the main causes of freshwater eutrophication. Studies have showed that decades of N fertilization at rates exceeding the amount removed by crops have resulted in widespread accumulation of N in agricultural soils in Taihu Lake basin, and the accumulation of N will increase the potential of soil N loss to surface and ground waters. Therefore studying the spatial variability of soil N at large scale will be helpful to develop optimal management practices for controlling agricultural nonpoint N pollution. Geostatistics has proven to be useful for characterizing and mapping spatial variability of soil properties. In this paper, a geostatistics method, combined with Geographic Information System (GIS), was applied to analyze the spatial variability of total soil N in topsoil in the typical area of Taihu Lake basin. The results showed that the spatial variability of total soil N was apparent in isotropy within the maximum lag extent of 40km, beyond which the anisotropy of spatial variability was increasing due to the change of soil parent materials in the direction of NE34°. The isotropic semivariograms showed that the ratio of nugget to sill of the total soil N was about 0.5,indicating that the total soil N had a relatively good spatial autocorrelation in the study area, and the range of autocorrelation extended to about 16km. The map of the total soil N interpolated through Block Kriging based on the fitted exponential model depicted that the soils in Jiangyin and Yixing counties generally had much more N than that in the other counties,which was mainly contributed to the different application levels of N fertilizers;and the "hot spots" of high soil N content were apparent in low-lying polderland, which probably was the results of interaction of topography and human factors such as fertilization.

Key words: total soil nitrogen, geostatistics, spatial variability, Kriging