Habitat Heterogeneity and Spatio-Temporal Distribution of Macrobenthos in in a Tropical Estuarine Mangrove Ecosystem

This paper deals with spatio-temporal distribution of macrobenthos and their relationship with physico-chemical environment and sediment properties in estuarine mangrove ecosystem of Chorao, Goa. The complex mangrove habitats provide nutrient and play vital role in the establishment of healthy mangrove fauna. The mangrove of Chorao is inhabited by 14 species of mangrove and associated flora in different substrata. The macrofaunal density in the four study stations varied significantly. Total numerical count was 7960 at C1, 3300 at C2, 6705 at C3 and 7075 at C4. The wet weight biomass was 27.18 at C1, 17. 62 at C2, 15.85 at C3 and 24.30 at C4. There was strong seasonality in the occurrence of fauna in the study area. The average macrofaunaltaxa was dominated by polychaeta (55%), crustacea (26%) and mollusca (14%). The other groups like nematode, echiurida and nemertenea was insignificant. The epibenthic feeding forms of polychaetes and scavengers/browsers of crustacean were more common in the sandy substratum, while deposit feeders were common in muddy substratum at Chorao mangrove. The result of the present study suggests that mangrove ecosystem with different substrata and physico-chemical parameters supports varied fauna and had different effect on the benthic community.