干旱区研究 ›› 2023, Vol. 40 ›› Issue (3): 481-491.doi: 10.13866/j.azr.2023.03.14

• 生态与环境 • 上一篇    下一篇

基于组合熵权RSR法的董志塬沟谷发育评价

崔帅(),许强(),袁爽,蒲川豪,陈婉琳,纪续   

  1. 成都理工大学,地质灾害防治与地质环境保护国家重点实验室,四川 成都 610059
  • 收稿日期:2022-08-02 修回日期:2022-10-01 出版日期:2023-03-15 发布日期:2023-03-31
  • 通讯作者: 许强. E-mail: xq@cdut.edu.cn
  • 作者简介:崔帅(1999-),男,硕士研究生,研究方向为地质灾害. E-mail: 1458069577@qq.com
  • 基金资助:
    国家自然科学基金重大项目(41790445)

Evaluation of Dongzhi Loess Plateau Gully development based on combined entropy weight Rank-Sum Ratio method

CUI Shuai(),XU Qiang(),YUAN Shuang,PU Chuanhao,CHEN Wanlin,JI Xu   

  1. State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, Sichuan, China
  • Received:2022-08-02 Revised:2022-10-01 Online:2023-03-15 Published:2023-03-31

摘要:

黄土沟谷的发育演化进程研究对于发掘沟谷形成与土壤侵蚀的内在机理,指导黄土地区生态修复有深刻的指导意义。基于沟谷水平空间、气候、沟谷点线面特征选取10个沟谷发育程度量化指标,利用组合熵权RSR法优异的多因子综合性分档评价能力建立董志塬沟谷发育阶段分级评价模型,探究黄土沟谷的发育演化及分布规律。研究发现:(1) 基于熵权法计算归一化植被指数(NDVI)所占权重最高为16.08%,其次为沟谷密度(15.621%),两者是判断沟谷发育程度的重要指标。(2) 基于组合熵权RSR法将董志塬82条沟谷发育程度分为幼年期、青年期、壮年期和老年期,壮年期和老年期沟谷面积占比为88.48%,董志塬东部及北部发育程度较高,对于塬面侵蚀强烈。(3) 沟谷发育程度与其下伏古地貌、构造地质和黄土厚度有着高度相关性。(4) 模型方差一致性检验显著性水平P<0.001,线性回归拟合优度R2为0.986,评价模型表现良好。

关键词: 黄土, 量化指标体系, 组合熵权RSR法, 沟谷发育分级评价, 董志塬

Abstract:

As a typical erosion geomorphic unit in the loess areas, gullies continuously erode loess surface under the action of internal and external forces, rainfall, and other factors. There are significant differences in the degree of development of gullies and valleys. Evaluating the development pattern of gullies and valleys can enhance the understanding of their organized, systematic formation and evolution. In addition, comprehensive quantitative indexes can facilitate the understanding of the longitudinal, lateral, and horizontal characteristics of gullies and valleys from multiple perspectives, which can help in the accurate and effective implementation of gully consolidation and loess protection projects, and reduce the constraints on development caused by this fragile geological environment. Evaluating the development of loess valleys is also crucial for exploring the intrinsic mechanism of valley formation, soil erosion, and guiding the ecological restoration of loess areas. In this study, ten quantitative indicators of gully development were selected based on the horizontal spatial, climatic, and point-line characteristics of the gullies, and used to establish an indexed evaluation model of the developmental stages of Dongzhi Loess Plateau gullies based on the efficient multi-factor comprehensive indexing evaluation capacity of the combined entropy-weight rank-sum ratio (RSR) method. Results showed that: (1) The highest weight of 16.08% could be attributed to the normalized vegetation index (NDVI) based on the entropy weighting method, followed by gully density (15.621%), both of which are important indicators for predicting the degree of gully development. (2) The combined entropy weighting RSR method could classify the 82 gullies of Dongzhi Loess Plateau into juvenile, youth, prime, and old age categories, with the percentage of gully area under the prime and old age categories accounting for 88.48% and 88.48%, respectively, while the eastern and northern parts of Dongzhi Loess Plateau exhibited more developed features and strong erosion on the loess surface. (3) The degree of gully development was highly correlated with the underlying palaeomorphology, tectonic geology, and loess thickness. (4) A significant model variance consistency test at P<0.001, with a linear regression R2 fit of 0.986 was observed, which indicated a good performance of the model.

Key words: loess, quantitative index system, combined entropy-weighted RSR method, graded evaluation of gully development, Dongzhi Loess Plateau