干旱区绿洲农田土壤大孔隙与水分入渗特征
作者:
作者单位:

作者简介:

通讯作者:

中图分类号:

S152.7

基金项目:

国家自然科学基金项目(41877153,42071044)、中国科学院A类先导专项(XDA23060302)、中国科学院青年创新促进会会员(2020420)资助


Characteristics of Soil Macropores and Water Infiltration in Oasis Croplands in an Arid Region
Author:
Affiliation:

Fund Project:

National Natural Science Foundation of China (No. 41877153, 42071044), the Strategic Priority Research Program of the Chinese Academy of Sciences (No. XDA23060302), the Youth Innovation Promotion Association CAS (No. 2020420)

  • 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:

    土壤大孔隙虽然占土壤总孔隙的极少部分,但影响着土壤水分入渗途径和过程。本研究以干旱区山前绿洲、老绿洲、边缘绿洲三种典型绿洲农田为研究对象,通过原位染色示踪和CT扫描技术,定量研究了绿洲农田的大孔隙特征和土壤水分入渗性能。结果表明:绿洲农田的土壤大孔隙大多集中在0~20 cm土层,老绿洲农田的大孔隙三维结构较山前绿洲农田和边缘绿洲农田复杂,其土壤大孔隙度、分形维数、分支密度、连接点密度、连通性指数显著大于山前绿洲和边缘绿洲农田(P<0.05)。绿洲农田的稳定入渗率存在显著性差异(P<0.05),表现为:边缘绿洲(0.48 mm·min-1)>老绿洲(0.28 mm·min-1)>山前绿洲(0.16 mm·min-1)。绿洲农田水分的入渗特征呈现异质性,入渗的染色面积比随土层深度增加而减小,老绿洲的优先流长度指数、最大入渗深度显著高于山前绿洲和边缘绿洲(P<0.05),其优先流现象明显。在干旱区绿洲农田,土壤大孔隙是影响优先流的关键因素,土壤的大孔隙度高,且连通性好,更容易产生优先流。

    Abstract:

    [Objective] Soil macropores in oasis croplands account for a low ratio of the total soil porosity, but significantly influence the path and process of soil water infiltration. Therefore, it is necessary to explore or characterize soil macropores and their effects on the water infiltration process in arid regions.[Method] In this study, we selected three types of oasis croplands(piedmont oasis cropland, old oasis cropland, and marginal oasis cropland), using in-situ dye tracer experiment and a helical medical X-ray computed tomography (CT), the characteristics of soil macropores and water infiltration in the three oasis croplands were quantitatively investigated.[Result] The results showed that soil macropores in the oasis croplands were mainly concentrated in the 0-20 cm soil layer. The three-dimensional macropore structure in the old oasis cropland was more complex than those of piedmont oasis and marginal oasis croplands. Also, the soil macroporosity, fractal dimension, branch density, junction density, and connectivity density in the old oasis cropland were significantly (P<0.05) higher than those of piedmont oasis and marginal oasis. Besides, there was a significant (P<0.05) difference in the steady infiltration rates between the three types of oasis croplands. The steady infiltration rates were of the order marginal oasis cropland (0.48 mm ·min-1) > old oasis cropland (0.28 mm·min-1) > piedmont oasis cropland (0.16 mm·min-1). The dyed area of water infiltration in croplands decreased with the depth of the soil layer. Also, the maximum infiltration depth and preferential flow length index in old oasis cropland were significantly (P<0.05) higher than that in piedmont oasis and marginal oasis croplands, and the degree of preferential flow was also the highest.[Conclusion] In oasis croplands of arid regions, the characteristics of soil macropores are the key factors affecting preferential flow. The oasis soils with high macroporosity and connectivity are more likely to produce preferential flow, resulting in soil water moving to the deep soil layer. It was observed that old oasis cropland had higher macroporosity and pore connectivity than the other oasis croplands, and demonstrated the most obvious degree of preferential flow. This study provides an in-situ measurement technique and database for the study of preferential flow in arid regions.

    参考文献
    相似文献
    引证文献
引用本文

贾昂元,张勇勇,赵文智,康文蓉.干旱区绿洲农田土壤大孔隙与水分入渗特征[J].土壤学报,2022,59(2):486-497. DOI:10.11766/trxb202006180316 JIA Angyuan, ZHANG Yongyong, ZHAO Wenzhi, KANG Wenrong. Characteristics of Soil Macropores and Water Infiltration in Oasis Croplands in an Arid Region[J]. Acta Pedologica Sinica,2022,59(2):486-497.

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:2020-06-18
  • 最后修改日期:2021-01-11
  • 录用日期:2021-04-30
  • 在线发布日期: 2021-05-11
  • 出版日期: 2022-02-11