干旱区研究 ›› 2019, Vol. 36 ›› Issue (6): 1325-1332.

• 水土资源 • 上一篇    下一篇

西北干旱区土壤水力参数空间变异与模拟

李祥东1, 2,邵明安1, 2, 3,赵春雷3   

  1. 1.中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,陕西 杨凌 712100;

    2.中国科学院大学资源与环境学院,北京 100190; 

    3.中国科学院地理科学与资源研究所,北京 100101

  • 收稿日期:2019-01-17 修回日期:2019-03-04 出版日期:2019-11-15 发布日期:2019-11-15
  • 通讯作者: 邵明安
  • 作者简介:李祥东(1990-),男,博士研究生,主要从事土壤物理研究. E-mail: xiangdong90@gmail.com
  • 基金资助:

    国家自然科学基金项目(4153085441571130081)资助

Spatial Variability and Simulation of Soil Hydraulic Parameters in Arid Northwest China

LI Xiang-dong1, 2, SHAO Ming-an1, 2, 3, ZHAO Chun-lei3   

  1. 1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, Shaanxi Province, China;
    2. College of Natural Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China;
    3. Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China

  • Received:2019-01-17 Revised:2019-03-04 Online:2019-11-15 Published:2019-11-15

摘要:

为探明西北干旱区土壤水力参数的空间分布特征,在新疆地区布设107个样点,获取表层(0~5 cm)Ks(土壤饱和导水率)、FC(田间持水量)和PWP(永久萎蔫系数)数据,采用经典统计学和地统计学分析土壤水力参数的空间变异特征,并利用逐步回归和传递函数方程对Ks、FC和PWP进行模拟。结果表明:新疆地区Ks、FC和PWP平均值分别为10.999 mm·h-1、0.162 g·g-1 和0.077 g·g-1,变异系数为39.88% ~ 96.07%,均表现为中等程度变异。在区域尺度上Ks、FC和PWP具有强空间依赖性,变程为97 ~ 291 km。与经自变量数据转换构建的传递函数方程相比,多元逐步回归方程预测土壤水力参数精度更高,且方程使用更便利。基于土地利用、容重、土壤质地、有机碳含量和坡向的多元逐步回归方程,预测Ks、FC和PWP的决定系数R2分别为0.290、0.494和0.491,均方根误差(RMSE)分别为2.540 mm·h-1,0.039 g·g-1和0.023 g·g-1。这些方程的建立,有利于西北干旱区土壤水力参数的快速估算,同时可为该地区的农业灌溉和生态水文模型提供关键参数。

关键词: 土壤饱和导水率, 田间持水量, 永久萎蔫系数, 区域尺度, 多元逐步回归, 新疆

Abstract: Soil saturated hydraulic conductivity (Ks), field capacity (FC) and permanent witling percentage (PWP) are the important soil hydraulic parameters. These parameters are also the critical factors in bio-hydrologic models. In order to understand the regional-scale spatial variability of these hydraulic parameters, the Ks, FC and PWP data (0-5-cm soil layer in depth) were obtained from 107 sampling sites in Xinjiang. Both traditional statistics and geostatistics were used to explore the spatial variations of Ks, FC and PWP. Estimations of these parameters were further conducted by multiple stepwise regression (MSR) and pedotransfer functions (PTFs). The results indicated that the mean values of Ks, FC and PWP were 10.999 mm·h-1, 0.162 g·g-1 and 0.077 g·g-1 respectively. These three hydraulic parameters varied moderately with Cvs of 39.88%-96.07%, and had strong spatial correlations in a range of 97-291 km in Xinjiang. MSR performed better than PTFs in estimating soil hydraulic parameters. Based on the land use, bulk density, soil texture, soil organic carbon content and slope aspect, the determination coefficients of the MSR models for Ks, FC and PWP were 0.290, 0.494 and 0.491, and the root mean square errors were 2.540 mm·h-1,0.039 g·g-1 and 0.023 g·g-1, respectively. The development of these equations is beneficial to the rapid estimation of soil hydraulic parameters and can thus provide the key parameters for the agricultural irrigation and eco-hydrological models in arid northwest China.

Key words: soil saturated hydraulic conductivity, field capacity, permanent witling percentage; regional scale, multiple stepwise regression, Xinjiang