Benthic studies in Goa estuaries: Part I - Standing crop and faunal composition in relation to bottom salinity distribution and substratum characteristics in the estuary of Mandovi river

41-45Benthic standing crop and faunal composition in relation to salinity intrusion and sediment types have been investigated in the estuary of Mandovi river, during December 1971 to January 1972. The estuary has a steep, salinity gradient with a variation of 31.7% over a distance of 35.4 km. The tidal action is weak and freshwater dominance is clearly seen. Bottom salinity values demonstrate the existence of 4 different salinity zones. Substratum types, as determined by visual examination and median grain-size analysis, show the existence of four sediment zones which are comparable with salinity zones, in longitudinal expanse. The results demonstrate the influence of salinity and substratum on the benthic production and distribution of fauna. The present investigation forms baseline study for assessment and management of benthic resources