地理科学 ›› 2003, Vol. 23 ›› Issue (6): 728-733.doi: 10.13249/j.cnki.sgs.2003.06.728

• 论文 • 上一篇    下一篇

撂荒后黄土高原坡耕地土壤透水性和抗冲性的变化

罗利芳1, 张科利1,2, 李双才1   

  1. 1. 北京师范大学资源与环境科学系, 北京 100875;
    2. 黄土高原土壤侵蚀 与旱地农业国家重点实验室, 陕西 杨陵 712100
  • 收稿日期:2002-11-21 修回日期:2003-03-15 出版日期:2003-11-20 发布日期:2003-11-20
  • 基金资助:
    国家自然科学基金重大项目(40235056)、黄土高原土壤侵蚀和旱地农业国家重点实验室基金(10501-110)资助。

Change in Soil Permeability and Anti-scourability of Farmland after Abandonment

LUO Li-Fang1, ZHANG Ke-Li1,2, LI Shuang-Cai1   

  1. 1. The Department of Resource and Environmental Science, Beijing Normal University, Beijing 100875;
    2. State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau, Yangling, Shaanxi 712100
  • Received:2002-11-21 Revised:2003-03-15 Online:2003-11-20 Published:2003-11-20

摘要: 退耕政策实施后,黄土高原部分坡耕地以撂荒形式来恢复其生态环境,而有关撂荒后土壤性质动态变化的研究还很少。土壤透水性和抗冲性是两个与水土流失关系最为密切的土壤性状指标。通过对黄土高原典型退耕区不同年限撂荒地的表土透水性和抗冲性及其它土壤性质的研究,表明土壤抗冲性随撂荒时间延长变化最大,其次为透水性、非毛管孔隙度和有机质,而容重、饱和含水量、毛管含水量、田间持水量、总孔隙度、毛管孔隙度等随撂荒时间变化相对很小。随着撂荒时间的延长,土壤的抗冲性、透水性都明显的增强。撂荒5年后,水土流失得到很大程度控制,土壤质量也可得到改善。

Abstract: The Loess Plateau is well known for its severe soil erosion because of the erodible soil, unreasonable land use and natural vegetation damage. Intense soil loss results in depletion in farmland, deteriorating ecological environment and plethoric silt in channel and so on. Therefore, an important policy was established to return the cropland to forest and grassland on the Loess Plateau. After carrying out the policy, most of croplands have been left alone in their wildness on the Loess Plateau. But little research has been conducted on the change of the soil properties on these lands, especially for the properties closely related to soil erosion. The permeability and anti-scourability are two very important indexes of soil properties. The permeability indicates the potential to produce runoff which is one of the main forces of soil erosion. The anti-courability is the ability of soil to defend the scouring of the flow. The typical region of Ansai was selected to study the permeability, anti-scourability and other soil properties of these lands after being wild for different years. Anti-scourability was measured in a hydraulic flume with slope gradient 15癮nd flow discharge of 1,2,3,4,5L/s. The saturated hydraulic conductivity, organic matter, bulk density, saturated water content, capillary water content and field capacity were aslo measured. The results indicated that the scoured soil module changed most markedly, and the saturated hydraulic conductivity, non-capillary porosity, and organic matter also varied greatly, with the indexes of bulk density, saturated water content, capillary water content, field capacity, total porosity, and capillary porosity altering comparatively little. The permeability linearly increased about 0.044mm/min a year after being wild with solidifying by plant roots, increasing organic matter and non-capillary porosity. The scoured soil module exponentially decreased. That is to say, the soil anti-scourabiltiy improved greatly with the increasing time of being wild, in which plant roots also play a very important role. In addition, soil bulk density indicated some relationship with the soil anti-scourabiltiy and permeability. It was shown that the soil and water loss was controlled to a great extent and soil quality also improved after being wild for over 5 years.

中图分类号: 

  • S157.1