干旱区生态环境知识资源中心(Arid): Monitoring the Dynamics of Ephemeral Rivers from Space: An Example of the Kuiseb River in Namibia

Arid

DOI	10.3390/w14193142
	Monitoring the Dynamics of Ephemeral Rivers from Space: An Example of the Kuiseb River in Namibia
	Normandin, Cassandra; Paillou, Philippe; Lopez, Sylvia; Marais, Eugene; Scipal, Klaus
通讯作者	Normandin, C
来源期刊	WATER
EISSN	2073-4441
出版年	2022
卷号	14 期号:19
英文摘要	Ephemeral rivers are characterized by brief episodic flood events, which recharge subterraean alluvial aquifers that sustain humans, riparian vegetation, and wildlife in the hyper-arid Namib Desert. Yet we only have a poor understanding of the dynamics and feedback mechanisms in these hydrological systems as arid and semi-arid zones are typically poorly equipped with reliable in situ monitoring stations to provide necessary information. The main objective of our study is to show the potential of satellite data to monitor the dynamics of ephemeral rivers, such as the Kuiseb located in Namibia, since remotesensing offers the advantage of adapted spatial and temporal resolutions. For this study, multi-spectral imagery (Sentinel-2), Synthetic Aperture Radar (SAR, Sentinel-1), and SAR interferometry (Sentinel-1) data were used to produce Normalized Difference Vegetation Index (NDVI) maps, backscattering maps (as sigma(0)), and interferograms, respectively. These parameters provide information on the hydrologic and vegetation dynamics of the river. Strong variations in NDVI, sigma(0), and interferograms are observed during March-April 2017 and June-July 2018 in a tributary of the Kuiseb in the central Namib Desert. In those years, rain events caused the reactivation of the tributary. However, during a major flood in 2021, when no rain occured, no variations in NDVI were detected in this tributary, unlike the sigma(0) and interferogram anomalies after the flood. Thus, these variations cannot be explained by rains, which were non-existent during this period, but seem to be linked to the dynamics of the aquifer of the Kuiseb River, wherein floods recharge the alluvial aquifers and the rising water table levels produce a signal that is measurable by satellite radar sensors. All these results present a preliminary work that might be used by water resource managers to automate the processing and methods used to create an ephemeral river monitoring tool.
英文关键词	fluvial aquifer hydrology groundwater monitoring multispectral imagery radar backscattering interferometry
类型	Article
语种	英语
开放获取类型	gold
收录类别	SCI-E
WOS记录号	WOS:000867114000001
WOS关键词	RECHARGE ; WATER
WOS类目	Environmental Sciences ; Water Resources
WOS研究方向	Environmental Sciences & Ecology ; Water Resources
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/394837
推荐引用方式 GB/T 7714	Normandin, Cassandra,Paillou, Philippe,Lopez, Sylvia,et al. Monitoring the Dynamics of Ephemeral Rivers from Space: An Example of the Kuiseb River in Namibia[J],2022,14(19).
APA	Normandin, Cassandra,Paillou, Philippe,Lopez, Sylvia,Marais, Eugene,&Scipal, Klaus.(2022).Monitoring the Dynamics of Ephemeral Rivers from Space: An Example of the Kuiseb River in Namibia.WATER,14(19).
MLA	Normandin, Cassandra,et al."Monitoring the Dynamics of Ephemeral Rivers from Space: An Example of the Kuiseb River in Namibia".WATER 14.19(2022).