Hydrological code

Abstract: A morphometric analysis of Bharathapuzha river basin has been carried out using geoprocessing techniques in GIS. This technique is found relevant for the extraction of river basin and its drainage networks. The extracted drainage network was classified according to Strahler’s system of classification and it reveals that the terrain exhibits dendritic to sub-dendritic drainage pattern. The Bharathapuzha drainage basin is sprawled over an area of 5,988.56 km2. The study area was designated as seventh-order basin and lower order streams mostly dominate the basin with the drainage density value of 1.07 km/km2. The slope of basin varied from 0° to 70° and the slope variation is chiefly controlled by the local geology and erosion cycles. The elongation ratio of the basin is 0.57 indicating that the study area is elongated with moderate relief and steep slopes. The drainage texture of the basin is 7.78 which indicates an intermediate texture that exists over the region. Hence, from the study, it can be concluded that remote sensing data (SRTM–DEM) coupled with geoprocessing techniques prove to be a competent tool in morphometric analysis and the data can be used for basin management and other hydrological studies in future.

Abstract: Using the multi-scale entropy analysis (MSE), we study the effects of water reservoirs on the river flow records based on long streamflow series covering January 1, 1954 and December 31, 2009 at four representative hydrological stations, i.e. the Longchuan, the Heyuan, the Lingxia and the Boluo stations. Hydrological effects of two major water reservoirs, the Xinfengjiang and the Fengshuba water reservoirs, are evaluated. The results indicate that: (1) before the construction of the water reservoirs, the complexity of the streamflow series comes to be decreasing from the upper to the lower East River and which should be attributed to the topographical properties and buffering effects of the river channel; (2) construction of water reservoirs greatly increases the complexity degree of the hydrological processes, and this influence is subjected to a damping process with the increase of distance between the water reservoirs and the hydrological stations; (3) power generation is the major function of the water reservoirs in the East River basin. The results of this study should be of theoretical and scientific merits in terms of conservation of the ecological environment and also water resources management under the influences of climate changes and intensifying human activities. Copyright © 2011 John Wiley & Sons, Ltd.