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中国沙漠 ›› 2014, Vol. 34 ›› Issue (1): 16-22.DOI: 10.7522/j.issn.1000-694X.2013.00280

• 沙漠与沙漠化 • 上一篇    下一篇

包兰铁路沙坡头段防护体系内的风沙沉降规律

张加琼1, 张春来1, 吴晓旭1, 李君丞2   

  1. 1. 北京师范大学 地表过程与资源生态国家重点实验室/防沙治沙教育部工程研究中心, 北京 100875;
    2. 成都市金牛区环境保护局, 四川 成都 610036
  • 收稿日期:2013-02-25 修回日期:2013-04-07 出版日期:2014-01-20 发布日期:2014-01-20
  • 作者简介:张加琼(1984- ),女,四川小金人,博士研究生,研究方向为土壤风蚀。Email:jqzhang@mail.bnu.edu.cn
  • 基金资助:
    国家自然科学基金项目(41171004)资助

Aeolian Deposition in the Protective System of Shaopotou Section of the Baotou-Lanzhou Railway

Zhang Jiaqiong1, Zhang Chunlai1, Wu Xiaoxu1, Li Juncheng2   

  1. 1. State Key Laboratory of Earth Surface Processes and Resource Ecology/MOE Engineering Center of Desertification and Blown-sand Control, Beijing Normal University, Beijing 100875, China;
    2. Jinniu District Environmental Protection Agency of Chengdu, Chengdu 610036, China
  • Received:2013-02-25 Revised:2013-04-07 Online:2014-01-20 Published:2014-01-20
  • Contact: 张春来,clzhang@bnu.edu.cn

摘要: 对沙坡头铁路防护体系内的风沙沉降进行了断面观测,据此分析了沉降速率、粒度组成和物源的时空变化规律。结果显示:防护体系前沿流沙区、防护距离50~300 m的植被区和300 m以外的植被区风沙沉降速率分别为108.6、17.1 kg·m-2·a-1和1.5 kg·m-2·a-1。随防护距离增大,沉降颗粒逐渐变细,分选变差,跃移组分含量逐渐减少而悬移组分含量逐渐增大,沉降来源逐渐由前沿流沙区近地面风沙运动颗粒转变为以大气降尘为主的悬移颗粒。年内风沙沉降的高峰期为3-5月,6-8月沉降减弱,9月至次年2月风沙沉降最弱,3个阶段内防护体系植被区月均沉降量分别为0.59、0.10 kg·m-2和0.04 kg·m-2。3-5月风沙沉降以上风向邻近区域的风蚀起沙为主,6-8月较远源的大气降尘相对增加而上风向邻近区域的风蚀起沙相对减少,9月至次年2月风沙沉降物源以大气降尘为主。

关键词: 防护体系, 风沙沉降, 粒度, 物源, 时空变化

Abstract: This paper investigated spatial and temporal distribution of the aeolian deposition in the protective system of Shapotou section of Baotou-Lanzhou Railway and analyzed the deposition rate, grain size composition and material source. The results show that the deposition rate is 108.6, 17.1 kg·m-2·a-1 and 1.5 kg·m-2·a-1 in the front moving sand area, the area of protective distance between 50 m and 300 m and the area of protective distance larger than 300 m in the protective system, respectively. The grain size of the aeolian deposition increases along the cross section and the sorting gets worse. The content of suspension particles increases while that of the saltation particle decreases with undulation caused by the fixed and semi-fixed dunes in the protective system. The aeolian deposition concentrates from March to May and reduces from June to August, whereas the other months experience the least deposition. The monthly aeolian deposits in the protective system during these three durations are 0.59, 0.1 kg·m-2 and 0.04 kg·m-2, respectively. The main source of the aeolian deposition from March to May is the saltation sands from the adjacent upwind moving sand area. Dust fall increases relatively and the sands from the adjacent upwind moving sand area reduce from June to August. From September to February of the next year, dust fall transported from long distance areas becomes the main source of the aeolian deposition.

Key words: protective system, aeolian deposition, grain size, material source, temporal and spatial distribution

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