Author(s): A. T. M. Hasan Zobeyer; M. Fazlul Bari; Nasreen Jahan
Linked Author(s):
Keywords: PHABSIM; Habitat preference; Instream flow; Weighted usable area; Ecological management
Abstract: Given a growing awareness of the need for ecologically sound water management worldwide, this research is aimed at the application and assessment of Physical Habitat Simulation (PHABSIM) model in the Surma River in Bangladesh, where importance of instream flow management has come into focus only recently due to the fact of diminished dry season flow and water sharing with riparian countries. The PHABSIM model for the Surma River was set up using a number of representative cross sections, water level-discharge relations at each cross section and habitat preference (depth, velocity and substrate) of adult life stage of 3 dominant fish species in the river. The model output shows the habitat availability for each of the selected fish species in terms of Weighted Usable Area (WUA) at different flows. This relationship between physical habitat and river flow was calculated by combined application of hydrodynamic and habitat model of PHABSIM. A comparison between model output and historical monthly median flows of the Surma River shows that the monthly median flow in the dry season is well below the water required for providing optimum habitat for selected fish species’ life stage while water is available in the wet season for this purpose. This type of observations permits the negotiation and setting of flow regimes optimal for ecological management and hence helps the planners in water resources development activities without affecting the river ecology.
Year: 2005