globalchange  > 气候变化与战略
DOI: 10.5194/hess-23-2679-2019
论文题名:
Distributive rainfall-runoff modelling to understand runoff-to-baseflow proportioning and its impact on the determination of reserve requirements of the Verlorenvlei estuarine lake; west coast; South Africa
作者: Watson A.; Miller J.; Fink M.; Kralisch S.; Fleischer M.; De Clercq W.
刊名: Hydrology and Earth System Sciences
ISSN: 1027-5606
出版年: 2019
卷: 23, 期:6
起始页码: 2679
结束页码: 2697
语种: 英语
Scopus关键词: Aquifers ; Biodiversity ; Catchments ; Climate change ; Ecosystems ; Evaporation ; Groundwater resources ; Lakes ; Rain ; Rivers ; Stream flow ; Agricultural expansion ; Climatic fluctuations ; Conservation priorities ; Exceedance probability ; Increased temperature ; Rainfall - Runoff modelling ; Rainfall-runoff modeling ; Streamflow variability ; Runoff ; aquifer characterization ; baseflow ; catchment ; demand analysis ; dominance ; evaporation ; rainfall-runoff modeling ; Ramsar Convention ; river flow ; temperature profile ; California ; South Africa ; South Africa ; Table Mountain ; Western Cape
英文摘要: River systems that support high biodiversity profiles are conservation priorities worldwide. Understanding river ecosystem thresholds to low-flow conditions is important for the conservation of these systems. While climatic variations are likely to impact the streamflow variability of many river courses into the future, understanding specific river flow dynamics with regard to streamflow variability and aquifer baseflow contributions is central to the implementation of protection strategies. While streamflow is a measurable quantity, baseflow has to be estimated or calculated through the incorporation of hydrogeological variables. In this study, the groundwater components within the J2000 rainfall-runoff model were distributed to provide daily baseflow and streamflow estimates needed for reserve determination. The modelling approach was applied to the RAMSAR-listed Verlorenvlei estuarine lake system on the west coast of South Africa, which is under threat due to agricultural expansion and climatic fluctuations. The sub-catchment consists of four main tributaries, Krom Antonies, Hol, Bergvallei and Kruismans. Of these, Krom Antonies was initially presumed the largest baseflow contributor, but was shown to have significant streamflow variability attributed to the highly conductive nature of the Table Mountain Group sandstones and Quaternary sediments. Instead, Bergvallei was identified as the major contributor of baseflow. Hol was the least susceptible to streamflow fluctuations due to the higher baseflow proportion (56%) as well as the dominance of less conductive Malmesbury shales that underlie it. The estimated flow exceedance probabilities indicated that during the 2008-2017 wet cycle average lake inflows exceeded the average evaporation demand, although yearly rainfall is twice as variable in comparison to the first wet cycle between 1987 and 1996. During the 1997-2007 dry cycle, average lake inflows are exceeded 85% of the time by the evaporation demand. The exceedance probabilities estimated here suggest that inflows from the four main tributaries are not enough to support Verlorenvlei, with the evaporation demand of the entire lake being met only 35% of the time. This highlights the importance of low-occurrence events for filling up Verlorenvlei, allowing for regeneration of lake-supported ecosystems. As climate change drives increased temperatures and rainfall variability, the length of dry cycles is likely to increase into the future and result in the lake drying up more frequently. For this reason, it is important to ensure that water resources are not over-allocated during wet cycles, hindering ecosystem regeneration and prolonging the length of these dry cycle conditions. © 2019 Author(s).
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/162952
Appears in Collections:气候变化与战略

Files in This Item:

There are no files associated with this item.


作者单位: Watson, A., Department of Earth Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa; Miller, J., Department of Earth Sciences, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa; Fink, M., Department of Geoinformatics, Friedrich Schiller University Jena, Loebdergraben 32, Jena, 07743, Germany; Kralisch, S., Department of Geoinformatics, Friedrich Schiller University Jena, Loebdergraben 32, Jena, 07743, Germany, German Aerospace Center (DLR), Institute of Data Science, Maelzerstraße 3, Jena, 07745, Germany; Fleischer, M., Department of Geoinformatics, Friedrich Schiller University Jena, Loebdergraben 32, Jena, 07743, Germany; De Clercq, W., Stellenbosch Water Institute, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa

Recommended Citation:
Watson A.,Miller J.,Fink M.,et al. Distributive rainfall-runoff modelling to understand runoff-to-baseflow proportioning and its impact on the determination of reserve requirements of the Verlorenvlei estuarine lake; west coast; South Africa[J]. Hydrology and Earth System Sciences,2019-01-01,23(6)
Service
Recommend this item
Sava as my favorate item
Show this item's statistics
Export Endnote File
Google Scholar
Similar articles in Google Scholar
[Watson A.]'s Articles
[Miller J.]'s Articles
[Fink M.]'s Articles
百度学术
Similar articles in Baidu Scholar
[Watson A.]'s Articles
[Miller J.]'s Articles
[Fink M.]'s Articles
CSDL cross search
Similar articles in CSDL Cross Search
[Watson A.]‘s Articles
[Miller J.]‘s Articles
[Fink M.]‘s Articles
Related Copyright Policies
Null
收藏/分享
所有评论 (0)
暂无评论
 

Items in IR are protected by copyright, with all rights reserved, unless otherwise indicated.