Physico-Chemical Features and Energy Input in 3 Sandy Beaches of West Coast of India

25-30Erosion of the beaches occurred during the southwest monsoon (June-September) and to a lesser extent during the northeast monsoon (November-December). Accretion occurred during the intervening months. Surf water temperatures were from 24 ° to 32 ° C and sand temperatures from 34 ° to 38 ° C. Salinity of the surf water was in the range 30 to 34% in the pre and post SW monsoon months. During the SW monsoon period the minimum salinity was 16, 20 and 24% at Arambol, Bawal and Colva respectively. Nutrient levels in the surf were highest during the SW monsoon months. Particulate organic carbon (POC) in surf water was the main source of energy input of energy input for benthic species. Levels of POC in sand and surf chlorophyll were relatively low. Levels of POC in the surf water did not show a consistent trend on the 3 beaches studied compared with a very characteristic seasonal pattern of animal numbers and biomass. This indicates that food availability is not a primary factor in controlling seasonal fluctuations of animal population of sandy beaches on the west coast of India