DOI: 10.5194/hess-19-657-2015
Scopus记录号: 2-s2.0-84961315213
论文题名: Drivers of spatial and temporal variability of streamflow in the Incomati River basin
作者: Saraiva Okello A ; M ; L ; , Masih I ; , Uhlenbrook S ; , Jewitt G ; P ; W ; , Van Der Zaag P ; , Riddell E
刊名: Hydrology and Earth System Sciences
ISSN: 10275606
出版年: 2015
卷: 19, 期: 2 起始页码: 657
结束页码: 673
语种: 英语
Scopus关键词: Agriculture
; Catchments
; Floods
; Forestry
; Geographic information systems
; Knowledge based systems
; Land use
; Rain
; Runoff
; Statistical methods
; Stream flow
; Timber
; Water management
; Watersheds
; Coefficient of variation
; Indicators of hydrologic alteration (iha)
; Irrigated agriculture
; Management decisions
; Spatial and temporal variability
; Trans-boundary rivers
; Water resource planning
; Water resource systems
; Water resources
; annual variation
; climate forcing
; flow regulation
; GIS
; hydrological regime
; land use
; spatiotemporal analysis
; statistical analysis
; streamflow
; water demand
; water management
; water planning
; water resource
; Agriculture
; Hydrology
; Rain
; Rivers
; Southern Africa
; Statistical Analysis
; Stream Flow
; Water Resources
; Komati Basin
英文摘要: The Incomati is a semi-arid trans-boundary river basin in southern Africa, with a high variability of streamflow and competing water demands from irrigated agriculture, energy, forestry and industries. These sectors compete with environmental flows and basic human water needs, resulting in a "stressed" water resource system. The impacts of these demands, relative to the natural flow regime, appear significant. However, despite being a relatively well-gauged basin in South Africa, the natural flow regime and its spatial and temporal variability are poorly understood and remain poorly described, resulting in a limited knowledge base for water resource planning and management decisions. Thus, there is an opportunity to improve water management, if it can be underpinned by a better scientific understanding of the drivers of streamflow availability and variability in the catchment. In this study, long-term rainfall and streamflow records were analysed. Statistical analysis, using annual anomalies, was conducted on 20 rainfall stations, for the period 1950-2011. The Spearman test was used to identify trends in the records on annual and monthly timescales. The variability of rainfall across the basin was confirmed to be high, both intra-and inter-annually. The statistical analysis of rainfall data revealed no significant trend of increase or decrease. Observed flow data from 33 gauges were screened and analysed, using the Indicators of Hydrologic Alteration (IHA) approach. Temporal variability was high, with the coefficient of variation of annual flows in the range of 1 to 3.6. Significant declining trends in October flows, and low flow indicators, were also identified at most gauging stations of the Komati and Crocodile sub-catchments; however, no trends were evident in the other parameters, including high flows. The trends were mapped using GIS and were compared with historical and current land use. These results suggest that land use and flow regulation are larger drivers of temporal changes in streamflow than climatic forces. Indeed, over the past 40 years, the areas under commercial forestry and irrigated agriculture have increased over 4 times. © 2015 Author(s). Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/78616
Appears in Collections: 气候变化事实与影响
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作者单位: UNESCO-IHE, Institute for Water Education, P.O. Box 3015, Delft, DA, Netherlands; Delft University of Technology, Department of Water Resources, P.O. Box 5048, Delft, GA, Netherlands; Centre for Water Resources Research, School of Agriculture, Earth and Environmental Science, University of KwaZulu-Natal, Private Bag X01, Scottsville, South Africa
Recommended Citation:
Saraiva Okello A,M,L,et al. Drivers of spatial and temporal variability of streamflow in the Incomati River basin[J]. Hydrology and Earth System Sciences,2015-01-01,19(2)