水土保持研究2024，Vol.31Issue(6)：96-102,108,8.DOI:10.13869/j.cnki.rswc.2024.06.008
渭河流域植被变化调控输沙的覆盖度阈值
Influence and Threshold of Vegetation Change on Sediment Load in the Weihe River Basin
摘要
Abstract
[Objective]The aims of this study are to analyze the spatiotemporal variation characteristics of vegetation coverage in the Weihe River Basin,to explore the correlation between vegetation coverage and sediment yield at the watershed scale,and to reveal the threshold of vegetation coverage based on sediment reduction benefits under the background of sediment load changes in the Weihe River.[Methods]The Weihe River Basin,a first-level tributary of the Yellow River,was selected.The vegetation change was analyzed,and the regulation effect of vegetation on sediment transport in the Weihe River Basin was quantified by using linear regression,F-test and piecewise linear regression.[Results]The vegetation coverage of Weihe River Basin showed a significant increasing trend from 2000 to 2019,and the average annual vegetation coverage growth rate was 0.005 5/a.The average annual sediment yield in the study area was higher in the north and lower in the south,and showed a decreasing trend except Juhe River.The main sediment source area was located in the upper reaches of Malian River and Beiluo River in the loess hilly and gully region.The sediment yield decreased with the increase of vegetation coverage,showing a negative exponential correlation,when the vegetation coverage reached to 45％,it could effectively control sediment load in the watershed.Vegetation coverage in Weihe River Basin could be divided into four coverage zones:low coverage zone(0～20％),transition coverage zone(20％～45％),high coverage zone(45％～70％)and very high coverage zone(70％～100％).The vegetation sediment reduction efficiency decreased stepwise with the increase of the coverage zone,and the vegetation sediment reduction efficiency in the very high coverage zone was only 1.9％and 6.0％of that in the low coverage zone and transition coverage zone.[Conclusion]The future vegetation restoration of the Loess Plateau should not only consider the difference of threshold of vegetation coverage in different regions,but also take into account the structure and function of vegetation restoration,so as to improve the diversity and stability of regional vegetation ecosystem.关键词
渭河流域/NDVI/植被覆盖度阈值/输沙量Key words
Weihe River Basin/NDVI/vegetation threshold/sediment loads分类
农业科学引用本文复制引用
赵彦博,赵广举,穆兴民,田鹏,耿韧,毕博..渭河流域植被变化调控输沙的覆盖度阈值[J].水土保持研究,2024,31(6):96-102,108,8.基金项目
国家自然科学基金(U2243211 （）
42177323 （）
42077076) （）
