Publication Date:
2018-02-08
Description:
Recession flows of a basin provide valuable information about its storage-discharge relationship as during recession periods discharge occurs due to depletion of storage. Storage-discharge analysis is generally performed by plotting − dQ / dt against Q , where Q is discharge at time t . For most real world catchments, − dQ / dt vs Q show a power-law relationship of the type: − dQ / dt = kQ α . Because the coefficient k varies across recession events significantly, the exponent α needs to be computed separately for individual recession events. The median α can then be considered as the representative α for the basin. The question that arises here is: what are the basin characteristics that influence the value of α ? Studies based on a small number of basins (up to 50 basins) reveal that α has good relationship with several basin characteristics. However, whether such a relationship is universal remains an important question, since a universal relationship would allow prediction of the value of α for any ungauged basin. To test this hypothesis, here we study data collected from a relatively large number of basins (358 basins) in USA, and examine the influence of 35 different physio-climatic characteristics on α . We divide the basins into two groups based on their longitudes and test the relationship between α and basin characteristics separately for the two groups. The results indicate that α is not identically influenced by different basin characteristics for the two datasets. This may suggest that the power-law exponent α of a region is determined by the way local physio-climatic forces have shaped the landscape.
Print ISSN:
0885-6087
Electronic ISSN:
1099-1085
Topics:
Architecture, Civil Engineering, Surveying
,
Geography
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