基于NDVI的清江流域植被覆被变化水沙效应分析  

Based on NDVI of Qingjiang River Basin under Vegetation Cover Change Analysis of Water and Sediment Effect

作　　者：刘昊 薛兴华 Liu Hao;Xue Xinghua(College of Forestry and Horticulture,Hubei University for Nationalities,Enshi 445000;Key Laboratory of Biological Resources Protection and Utilization,Enshi 445000)

机构地区：[1]湖北民族大学林学园艺学院,恩施445000 [2]生物资源保护与利用湖北省重点实验室,恩施445000

出　　处：《湖北林业科技》2025年第1期14-22,共9页Hubei Forestry Science and Technology

基　　金：国家自然科学基金项目(编号31460132)。

摘　　要：研究流域植被覆被变化下的河流水沙响应,阐明水沙效应的影响机制,进而为河流水沙治理提供科学支撑。结合1981—2002年清江流域长阳站径流泥沙资料,利用年均NDVI、年降水量、年径流量和年输沙量从年尺度,利用月均NDVI、月降水量、月径流量和月输沙量从季节尺度表征植被覆被变化与河流水沙的响应关系及植被覆被变化和降水量与河流水沙的综合响应关系。结果表明:(1)1981—2002年,植被覆被状况以每年0.004的趋势增加(P<0.01),年径流量、年输沙量按指数函数呈3.72亿m^(3)·a^(-1)、350400 t·a^(-1)的趋势减少(P<0.01)。(2)年尺度上,年均NDVI每增加0.1,年径流量减少约1771.48亿m^(3),年输沙量减少约32006800 t;年降水量每增加1 mm,年径流量增加约0.31亿m^(3),年输沙量增加约5100 t。河流水沙与植被覆被变化的相关性在变异年份(1990年)后增强,与降水量的相关性开始减弱,但综合来看,降水在调控河流水沙过程中仍起主导作用。(3)季节尺度上,植被物候冬季、雨季河流水沙响应敏感,径流量与植被覆被变化、降水量的相关性在变异月份(1月)之后开始减弱,而输沙量与其的相关性在变异月份(5月)之后开始增强,但综合来看,在属于植被物候夏季和雨季的6月,河流水沙响应特征尤为复杂多变。在水沙治理中,需特别关注植被物候夏季和雨季中的降水过程。The response relationship between vegetation cover change and river water and sediment was studied,and the influence mechanism of water and sediment effect was clarified,so as to provide scientific support for river water and sediment control.Based on the runoff and sediment data of Changyang station from 1981 to 2002,using the annual average NDVI,annual precipitation,annual runoff and annual sediment discharge from the annual scale,using the monthly average NDVI,monthly precipitation,monthly runoff and monthly sediment discharge from the seasonal scale,the response relationship between vegetation cover change and river water and sediment and the comprehensive response relationship between vegetation cover change and precipitation and river water and sediment were characterized.The results show that:(1)From 1981 to 2002,the vegetation cover increased with a trend of 0.004/a(P<0.01),and the annual runoff and annual sediment transport decreased by an exponential function of 372 million m^(3)·a^(-1) and 350400 t·a^(-1)(P<0.01).(2)On the annual scale,when the average annual NDVI increases by 0.1,the annual runoff decreases by about 177.148 billion m^(3),and the annual sediment discharge decreases by about 32006800 t.For every 1 mm increase in annual precipitation,the annual runoff increases by about 31 million m^(3),and the annual sediment transport increases by about 5100 t.The correlation between river flow and sediment and vegetation cover change increased after the variation year(1990),and the correlation with precipitation began to weaken.However,in general,precipitation still plays a leading role in regulating river flow and sediment.(3)On the seasonal scale,vegetation phenology is sensitive to river water and sediment in winter and rainy season.The correlation between runoff and vegetation cover change and precipitation began to weaken after the variation month(January),while the correlation between sediment discharge and sediment discharge began to increase after the variation month(May).However,on the whol

关 键 词：植被覆被变化 NDVI 降水量 水沙效应 清江流域 

分 类 号：P333[天文地球—水文科学]