干旱区生态环境知识资源中心(Arid): Quantifying the effects of climate and environmental changes on evapotranspiration variability in the Sahel

Arid

DOI	10.1016/j.jhydrol.2024.131874
	Quantifying the effects of climate and environmental changes on evapotranspiration variability in the Sahel
	Nkiaka, Elias; Bryant, Robert G.; Dembele, Moctar; Yonaba, Roland; Priscilla, Aigbedion Imuwahen; Karambiri, Harouna
通讯作者	Nkiaka, E
来源期刊	JOURNAL OF HYDROLOGY
ISSN	0022-1694
EISSN	1879-2707
出版年	2024
卷号	642
英文摘要	Whilst considerable research has been carried out to understand the effects of reforestation on evapotranspiration (ET), such studies are generally absent in the Sahel even though the region is currently undergoing extensive reforestation to halt desertification and land degradation. The objective of this study is to identify and quantify the dominant climatic and environmental factors influencing ET variability in the Sahel. However, achieving this goal in the Sahel is hindered by a lack of in situ monitoring data. To overcome this challenge, this study adopts geospatial datasets along with analytical methods to assess the climatic and environmental factors affecting ET in 45 watersheds in the Sahel over a period of four decades (1982-2021). Analyses show significant increasing trends in annual ET in more than 90% of the watersheds. Precipitation and mean temperature show significant increasing trends in all watersheds while windspeed, vapour pressure, solar radiation, specific humidity, and atmospheric evaporative demand show mixed results with both increasing and decreasing trends in different watersheds. Environmental variables including soil moisture, and vegetation cover measured using the normalised difference vegetative index (NDVI) also show consistent increasing trends in all watersheds. Statistical analyses further show that climatic and environmental factors contribute about 80% of ET variance. The relative contribution of climatic variables on ET variance is 75.11% while that of environmental variables is 24.71%. This suggests that climatic factors have a higher influence on ET variability than environmental factors. Analyses using the double logarithm elasticity model show that vapour pressure has the highest positive elasticity coefficient (2.58) on ET while net radiation has the highest negative elasticity coefficient (-9.58). This is the first study to cover the whole Sahelian belt from west to east and the results may be crucial for adopting climate-smart reforestation policies, enhance regional water management and improve our knowledge of vegetation- hydrology-climate interactions in the Sahel.
英文关键词	Analytical methods Elasticity concept Partial correlation coefficient Least square and double logarithm elasticity models Great green wall initiative NDVI
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:001301476300001
WOS关键词	GLOBAL EVAPOTRANSPIRATION ; VEGETATION ; STREAMFLOW ; IMPACTS ; DROUGHT ; TRENDS
WOS类目	Engineering, Civil ; Geosciences, Multidisciplinary ; Water Resources
WOS研究方向	Engineering ; Geology ; Water Resources
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/404613
推荐引用方式 GB/T 7714	Nkiaka, Elias,Bryant, Robert G.,Dembele, Moctar,et al. Quantifying the effects of climate and environmental changes on evapotranspiration variability in the Sahel[J],2024,642.
APA	Nkiaka, Elias,Bryant, Robert G.,Dembele, Moctar,Yonaba, Roland,Priscilla, Aigbedion Imuwahen,&Karambiri, Harouna.(2024).Quantifying the effects of climate and environmental changes on evapotranspiration variability in the Sahel.JOURNAL OF HYDROLOGY,642.
MLA	Nkiaka, Elias,et al."Quantifying the effects of climate and environmental changes on evapotranspiration variability in the Sahel".JOURNAL OF HYDROLOGY 642(2024).