干旱区研究 ›› 2023, Vol. 40 ›› Issue (12): 2016-2030.doi: 10.13866/j.azr.2023.12.14 cstr: 32277.14.j.azr.2023.12.14

• 生态与环境 • 上一篇    下一篇

浑善达克沙地西部新月形沙丘和抛物线沙丘共存区的地貌特征

任孝宗(),王嵩松,王亚梅,罗进洪,马永桃   

  1. 太原师范学院地理科学学院,山西 晋中 030619
  • 收稿日期:2023-04-20 修回日期:2023-10-04 出版日期:2023-12-15 发布日期:2023-12-18
  • 作者简介:任孝宗(1983-),男,博士,副教授,主要研究方向为风沙地貌、干旱区环境演变和水文地球化学. E-mail: renxzmail@126.com
  • 基金资助:
    山西省哲学社会科学规划课题(2023YY228);太原师范学院基础教育教学改革项目

Geomorphologic characteristics of the co-existence zone of barchan and parabolic dunes in western Hunshandake Sandy Land

REN Xiaozong(),WANG Songsong,WANG Yamei,LUO Jinhong,MA Yongtao   

  1. Taiyuan Normal University, School of Geographical Sciences, Jinzhong 030619, Shanxi, China
  • Received:2023-04-20 Revised:2023-10-04 Published:2023-12-15 Online:2023-12-18

摘要:

新月形沙丘和抛物线沙丘可以相互转化和共存,对共存区地貌特征的研究有助于对其形成原因的理解和为防沙治沙提供科学依据。本文基于Esri历史影像服务,对浑善达克沙地西部新月形沙丘和抛物线沙丘共存区3个时期(2008年1月15日、2011年6月4日和2016年9月20日)的沙丘形态参数进行了提取,并计算了沙丘的移动方向和移动速度。结果表明:典型新月形沙丘集中分布于沙地西部的15个与干湖盆有关的区域,雏形新月形沙丘和雏形抛物线沙丘则依次分布在干湖盆外围,干湖盆的出现是浑善达克沙地典型新月形沙丘发育的关键因素,对湖泊干涸引起的沙漠化应引起足够重视。对共存区最典型的5区分析发现,典型新月形沙丘和雏形新月形沙丘在涉及到两翼的形态参数分布模式上与雏形抛物线沙丘有明显差异。进一步对沙丘形态参数间的相关性分析发现,从新月形沙丘向抛物线沙丘的转变过程中,迎风坡长、背风坡长和底面积的变化具有继承性,两翼在该过程中变化最大。此外,3类沙丘的移动方向在数值上差异不大并与合成输沙势方向(RDD)的变化一致,但三者的移动速度差异明显,且影响不同类型沙丘移动速度的因素也不相同。其中,植被对植被覆盖状况相对良好的雏形抛物线沙丘影响最明显,表现为其移动速度与同时期的沙地NDVI变化趋势一致;而风速对植被覆盖较低的典型新月形沙丘和雏形新月形沙丘影响更显著,表现为其移动速度与同时期输沙势(DP)和合成输沙势(RDP)的变化趋势一致。此外,地形、沙源和人类活动对共存区沙丘的形态和移动均有影响。

关键词: 新月形沙丘, 抛物线沙丘, 共存, 形态和移动, 浑善达克沙地

Abstract:

Barchan and parabolic dunes can be transformed into each other and coexist in the same area, resulting in a unique landscape in which typical barchan dunes coexist with embryonic barchan and parabolic dunes. It is helpful to understand the causes of their formation and execute targeted desertification prevention and control projects after studying their spatial distribution, morphological characteristics, and migration. Based on the Esri historical image service (World Imagery Wayback), the morphological parameters of the dunes in the coexistence zone of the barchan and parabolic dunes, west of Hunshandake Sandy Land, were extracted in three periods: January 15, 2008, June 4, 2011, and September 20, 2016, and the direction and velocity of the dune migration were calculated. The results indicate that typical barchan dunes are concentrated in 15 areas related to the dry lake bed in the western part of the sandy land, whereas embryonic barchan and parabolic dunes are sequentially distributed around the periphery of the dry lake bed. The appearance of the dry lake bed was a key factor in the development of the typical barchan dunes in the Hunshandake Sandy Land. Therefore, more attention should be paid to the desertification caused by the lake drying up. The analysis of morphological parameters of sand dunes in the fifth zone, where the co-existence of barchan and parabolic dunes is typically found, indicates that the typical barchan and embryonic barchan dunes significantly differ from embryonic parabolic dunes. The correlation analysis between the morphological parameters of sand dunes indicates that toss slope length, lee slope length, and bottom area are inherited from the barchan to parabolic dunes, with horns experiencing the greatest changes during this process. Furthermore, the migration directions of the three types of dunes are almost equal but have varying migration velocities, as well as the factors that affect the migration of sand dunes. The most significant impact on the embryonic parabolic dunes, whose vegetation cover is relatively high, was the vegetation cover, whose variation was consistent with that of NDVI during the same period. The most significant impact on the typical barchan and embryonic barchan dunes, whose vegetation cover is relatively low, was wind speed, whose variation was consistent with that of DP and RDP during the same period. Additionally, other factors, including terrain, sand sources, and human activities, can influence the morphology and migration of barchan-parabolic dunes.

Key words: barchan dunes, parabolic dunes, coexistence, morphology and migration, Hunshandake Sandy Land