In situ effective clearance rate measurement of mangrove oysters (Crassostrea rhizophorae) in a tropical estuary in Brazil

摘要: Abstract Anthropogenic nutrient enrichment in estuaries induces high phytoplankton production, contributing to coastal eutrophication. Abundant natural banks of filter feeders, such as bivalves, downstream areas may contribute reducing symptoms eutrophication by decreasing biomass and amount material subjected microbial regeneration. The current concern is what extent bivalves can control water quality how environmental parameters influence the filtration process vice versa. In present study Crassostrea rhizophorae (Guilding, 1818) grazing ability on suspended particles their environment was determined situ, using biodeposition method uniquely constructed sediment traps. Additionally effect body size effective clearance rate (ECR) examined three different groups. experiment conducted Piraque-acu/Piraque-mirim estuary system, (Aracruz, ES, Brazil) during second week June 2012 (dry season). Environmental were measured together with total particulate matter (TPM, mg L-1) chlorophyll a analysis (CHL, μg at beginning end experiment. Average values recorded for TPM CHL 5.79 mg L-1 2.55 μg respectively very organic seston fraction (80%). reported (ECR, litres per hour) 17.99 L h-1g-1 dry weight (DW), one highest literature be associated detritus content feeding strategies comparison residing temperate environments. Weight length (height) relationship closely correlated (r = 0.73) however, standardized 1 g tissue did not vary significantly among classes. High ECR (POM, %) supports belief that exhibit flexibility according food quality.