测定尺度对所测土壤导水参数及其空间变异性的影响
作者:
作者单位:

作者简介:

通讯作者:

中图分类号:

基金项目:

该项目系美国农业部资助项目“Determination of soil hydraulic properties at different scales”,编号为“USDA-NRICGP, 1996-1999”


Effect of Measurement Scales on Measured Soil Hydraulic Properties and Their Spatial Variability
Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    用3种盘径(14.4,20,30cm)的负压入渗仪在2个供水负压(1和10cm)下,在65个测点测定了 田间水分入渗。基于入渗数据,计算了宏观毛管上升高度和2个基模吸力的导水率。导水率和宏观毛管 上升高度的值呈对数正态分布。用大盘径负压入渗仪测定获得的导水率和宏观毛管上升高度的空间连续 性最好。当供水负压为 1cm,盘径为 14.4cm(小盘径),导水率和宏观毛管上升高度的空间连续性没有表 现出来。导水率的均值随测定尺度增加而趋于减少,宏观毛管上升高度的均值和标准偏差均随测定尺度 增加而趋于减小。导水率和宏观毛管上升高度的样本半方差,半方差金砖方差(nugget)和平台方差(sill)随 测定尺度增加而减少。

    Abstract:

    A field experiment was conducted to study the spatial variability and scale dependence of soil hydraulic properties. Infiltrometers with three disc diameters (14. 4,20,and 30 cm)and 2 tensions(1 and 10 cm)were used to measure infiltration at 65 locations. With the infiltration data,hydraulic conductivity and macroscopic capillary length were calculated. The frequency distribution of hydraulic conductivity and macroscopic capillary length was log-normal. The spatial continuity of soil hydraulic conductivity and macroscopic capillary length was better displayed by measurements with large disc sizes. When tension was 1cm and disc diameter was 14. 4 cm,the spatial structure of hydraulic conductivity was not displayed. The mean of hydraulic conductivity and macroscopic capillary length tended to decrease as measurement scale (disc sizes)increased. The values of nuggets and sills of the sample variograms of hydraulic conductivity and macroscopic capillary length decreased as measurement scale increased.

    参考文献
    相似文献
    引证文献
引用本文

薛绪掌,张仁铎,桂胜祥.测定尺度对所测土壤导水参数及其空间变异性的影响[J].水土保持通报,2001,(3):47-50

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2001-01-15
  • 最后修改日期:
  • 录用日期:
  • 在线发布日期: 2014-11-28
  • 出版日期: