Distribution Characteristics of Soil Moisture for Different Types of Sand Dunes in the Central of Mu Us Sandy Land(PDF)
《地球科学与环境学报》[ISSN:1672-6561/CN:61-1423/P]
- Issue:
- 2015年第04期
- Page:
- 74-83
- Research Field:
- 水资源与环境
- Publishing date:
Info
- Title:
- Distribution Characteristics of Soil Moisture for Different Types of Sand Dunes in the Central of Mu Us Sandy Land
- Author(s):
- FU Chao-feng; ZHAO Jing-bo; BIAN Zi-hao; ZUO Jun
- 1. Key Laboratory of Western Mineral Resources and Geological Engineering of Ministry of Education, Chang’an University, Xi’an 710054, Shaanxi, China; 2. School of Tourism and Environment, Shaanxi Normal University, Xi’an 710119, Shaanxi, China; 3. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710061, Shaanxi, China
- Keywords:
- soil moisture; sand dune; inter-dune lowland; windward slope; leeward slope; vegetation; granularity; Mu Us sandy land
- PACS:
- P641.69
- DOI:
- -
- Abstract:
- The study area is located in the central of Mu Us sandy land, which belongs to the semiarid climate area with the annual precipitation of 350-400 mm. On the basis of the field investigation in late April 2009, the sand dunes were divided into bare migratory dune, shrub-covered dune and tree-covered dune according to the vegetation form and vegetation coverage on the surface of sand dunes, and the samples of drilling holes in the depth of 4 m at different microtopographies of sand dunes including windward slope, leeward slope and inter-dune lowland were taken for analyzing the changes of soil moisture and soil granularity characteristics. The results show that the average soil moistures of different microtopographies for shrub-covered dune and tree-covered dune in descending order are inter-dune lowland, windward slope and leeward slope; the average soil moistures in inter-dune lowland are higher than those in leeward slope and windward slope in bare migratory dune, but the changes of average soil moistures of leeward slope and windward slope are irregular; the differences of soil moistures of sampling sites in vertical subsections from the microtopographies of sand dunes are significant, and the variation trends are diverse; vegetation form and surface coverage significantly affect the change of soil moistures under the same microtopography of sand dunes, and the effect of shrub is more than that of tree; soil moistures of leeward slope and windward slope in vegetation-covered dune are generally higher than those in bare migratory dune, and the shallow bedrock aquifuge affects sharply soil moisture in inter-dune lowland; the relationship between soil moistures in vegetation-covered dune and contents of fine-sized soil (clay and silt, etc.) is significantly positive, and the surface vegetation improves the volume fraction of clay by means of trap fine-grained atmospheric dust and holds moisture.
Last Update: 2015-07-20