摘要
基于蒸散发(ET)、归一化植被指数(NDVI)及土地利用数据利用M-K检验、Sen趋势分析等方法,研究2001-2015年黄河流域ET时空分布及不同植被覆盖/土地利用下的ET变化规律。结果表明:(1)黄河流域年均ET呈东南高西北低的空间分布格局,与植被覆盖和土地利用的关系具有较好的一致性;(2)黄河流域ET、NDVI均呈现波动式增长状态,土地利用除草地外其他类型面积均有增加,上中下游的变化具有明显差异;(3)流域大部分地区ET与植被呈正相关关系,植被变化是影响ET的主要因素之一;(4)黄河流域土地利用类型对ET的响应时空差异比较明显。
The Yellow River Basin is mainly distributed in arid,semi-arid,and semi-humid areas with a fragile ecological environment,which has become the most serious soil erosion area in China and even in the world.Evapotranspiration(ET)is an essential part of the land water and energy cycle,playing a vital role in the global ecosystem regulation and the hydrological cycle.ET is mainly composed of vegetation and transpiration of soil water and different vegetation cover or land-use types,showing different spatial-temporal distribution characteristics.Accurate exploration of the ET’s spatial-temporal distribution and its response relationship is conducive to mastering regional surface water and heat balance law.Remote sensing has been widely used in ET’s dynamic monitoring on a global or regional scale.Analyzing the ET’s spatial-temporal changes in the Yellow River Basin promotes understanding the impact of vegetation and land-use changes on the water cycle and the rational allocation of water resources.On the basis of ET-MODIS data,normalized difference vegetation index(NDVI),and land-use products as data sources,we studied the ET’s spatial-temporal change pattern in the Yellow River Basin from 2001 to 2015 using the Manner-Kendall test and Sen’s trend analysis.We discussed ET’s impact and the different change characteristics under different NDVI conditions and land-use types.We found the following results:(1)The ET distribution pattern in the Yellow River Basin is obvious,gradually decreasing from southeast to northwest.The average ET value in the study area is 319.24 mm,and the average NDVI is 0.59.The high values of ET and NDVI are concentrated on the downstream areas,and their spatial distribution is in good consistent.(2)The time series of ET and NDVI in the Yellow River Basin all showed a fluctuant growth state,and the changes in each river segment were significantly different from 2001 to 2015.In inter-annual changes,the trends of ET and NDVI are the same,and they have a significantly increased level in the middle reaches.(3)Vegetation change is the main factor affecting ET,positively correlating with ET in most Yellow River Basin areas.(4)From 2001 to 2015,the area of land cover types in the Yellow River Basin except the weeding areas showed an increasing trend,in which the ET response in different river reaches was different to some extent.The spatial-temporal differences in land-use types in response to ET are obvious.It is of great significance for ecosystem protection and water resources management to comprehensively analyze the variation law of evaporation in the upper,middle,and lower reaches of the Yellow River Basin and provide a reference for promoting the sustainable development of the regional economy and society.
作者
谷佳贺
薛华柱
董国涛
周利娟
李静茹
党素珍
李尚志
GU Jiahe;XUE Huazhu;DONG Guotao;ZHOU Lijuan;LI Jingru;DANG Suzhen;LI Shangzhi(School of Surveying and Land Information Engineering,Henan Polytechnic University,Jiaozuo 454000,Henan,China;Yellow River Institute of Hydraulic Research,Zhengzhou 450003,Henan,China;Heihe Water Resources and Ecological Protection Research Center,Lanzhou 730030,Gansu,China)
出处
《干旱区地理》
CSCD
北大核心
2021年第1期158-167,共10页
Arid Land Geography
基金
国家自然科学基金面上项目(51779099)
中国保护黄河基金会项目(CYRF2018002)
中央级公益性科研院所基本科研业务费专项(HKY-JBYW-2017-10)。
关键词
蒸散发
植被覆盖
NDVI
土地利用
黄河流域
evapotranspiration
vegetation cover
NDVI
land use
Yellow River Basin
