气候变化领域集成服务门户(CCPortal): Spatial characterization of long-Term hydrological change in the Arkavathy watershed adjacent to Bangalore; India

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DOI	10.5194/hess-22-595-2018
	Spatial characterization of long-Term hydrological change in the Arkavathy watershed adjacent to Bangalore; India
	Penny G.; Srinivasan V.; Dronova I.; Lele S.; Thompson S.
发表日期	2018
ISSN	1027-5606
起始页码	595
结束页码	610
卷号	22 期号:1
英文摘要	The complexity and heterogeneity of human water use over large spatial areas and decadal timescales can impede the understanding of hydrological change, particularly in regions with sparse monitoring of the water cycle. In the Arkavathy watershed in southern India, surface water inflows to major reservoirs decreased over a 40-year period during which urbanization, groundwater depletion, modification of the river network, and changes in agricultural practices also occurred. These multiple, interacting drivers combined with limited hydrological monitoring make attribution of the causes of diminishing water resources in the watershed challenging and impede effective policy responses. To mitigate these challenges, we developed a novel, spatially distributed dataset to understand hydrological change by characterizing the residual trends in surface water extent that remain after controlling for precipitation variations and comparing the trends with historical land use maps to assess human drivers of change. Using an automated classification approach with subpixel unmixing, we classified water extent in nearly 1700 man-made lakes, or tanks, in Landsat images from 1973 to 2010. The classification results compared well with a reference dataset of water extent of tanks (R2ĝ€ Combining double low line ĝ€0.95). We modeled the water extent of 42 clusters of tanks in a multiple regression on simple hydrological covariates (including precipitation) and time. Inter-Annual variability in precipitation accounted for 63ĝ€% of the predicted variability in water extent. However, precipitation did not exhibit statistically significant trends in any part of the watershed. After controlling for precipitation variability, we found statistically significant temporal trends in water extent, both positive and negative, in 13 of the clusters. Based on a water balance argument, we inferred that these trends likely reflect a non-stationary relationship between precipitation and watershed runoff. Independently of precipitation, water extent increased in a region downstream of Bangalore, likely due to increased urban effluents, and declined in the northern portion of the Arkavathy. Comparison of the drying trends with land use indicated that they were most strongly associated with irrigated agriculture, sourced almost exclusively by groundwater. This suggests that groundwater abstraction was a major driver of hydrological change in this watershed. Disaggregating the watershed-scale hydrological response via remote sensing of surface water bodies over multiple decades yielded a spatially resolved characterization of hydrological change in an otherwise poorly monitored watershed. This approach presents an opportunity to understand hydrological change in heavily managed watersheds where surface water bodies integrate upstream runoff and can be delineated using satellite imagery.
语种	英语
scopus关键词	Agriculture; Classification (of information); Effluents; Groundwater; Land use; Precipitation (meteorology); Remote sensing; Reservoirs (water); Runoff; Satellite imagery; Surface waters; Tanks (containers); Water resources; Water tanks; Watersheds; Agricultural practices; Automated classification; Groundwater abstraction; Hydrological monitoring; Interannual variability; Precipitation variability; Precipitation variation; Spatial characterization; Rivers; complexity; groundwater abstraction; heterogeneity; hydrological change; hydrological response; land use; multiple regression; precipitation (climatology); remote sensing; satellite imagery; spatial analysis; surface water; water budget; watershed; Bengaluru; India; Karnataka
来源期刊	Hydrology and Earth System Sciences
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160137
作者单位	Penny, G., Department of Civil and Environmental Engineering, University of California, Berkeley, Berkeley, CA, United States; Srinivasan, V., Ashoka Trust for Research in Ecology and the Environment, Royal Enclave Sriramapura, Jakkur Post, Bangalore, Karnataka, India; Dronova, I., Department of Landscape Architecture and Environmental Planning, University of California, Berkeley, Berkeley, CA, United States; Lele, S., Ashoka Trust for Research in Ecology and the Environment, Royal Enclave Sriramapura, Jakkur Post, Bangalore, Karnataka, India; Thompson, S., Department of Civil and Environmental Engineering, University of California, Berkeley, Berkeley, CA, United States
推荐引用方式 GB/T 7714	Penny G.,Srinivasan V.,Dronova I.,et al. Spatial characterization of long-Term hydrological change in the Arkavathy watershed adjacent to Bangalore; India[J],2018,22(1).
APA	Penny G.,Srinivasan V.,Dronova I.,Lele S.,&Thompson S..(2018).Spatial characterization of long-Term hydrological change in the Arkavathy watershed adjacent to Bangalore; India.Hydrology and Earth System Sciences,22(1).
MLA	Penny G.,et al."Spatial characterization of long-Term hydrological change in the Arkavathy watershed adjacent to Bangalore; India".Hydrology and Earth System Sciences 22.1(2018).