Ecohydrology and fisheries of the upper Brahmaputra basin

摘要: The Brahmaputra changes its course and pattern along with current flow very frequently especially in upper stretches this has a strong bearing on hydrobiology. hydro-geological of the resulted possible zonation river into five major types fish habitat. Altogether 167 species have been recorded from which about 30 percent may be considered as ornamental varieties. Again, according to their seasonal availability, fauna grouped four principal categories. Among all hydrological factors, flood impulse is probably strongest factor that regulates other limnological conditions faunal distribution. Usually, there are three or high floods between May October migration intimately related regime. During dry season fishing mostly restricted near confluents tributaries channels also at meanders. However, large-scale felling trees catchment areas construction embankments banks altered riverine ecosystem drastically, result which, become heavily silted connecting floodplain lakes dammed. Consequently, fishes megafauna deprived adequate water cover, food supply breeding grounds. An ecohydrological approach advocated for habitat restoration.