Production and zooplankton community structure in the lagoon and surrounding sea at Kavaratti Atoll (Lakshadweep)

Abstract

Higher values for the environmental parameters were generally obtained for the lagoon stations. Average values of <i>p</i>H, temperature, salinity, dissolved oxygen and phosphate-phosphorus, nitrate-nitrogen, silicate and silicon in the lagoon were 7.5, 31.6ᵒC, 35.7 x 10^-3, ml.l^-1 and 0.8, 1.5 and 3.6 <i>µ</i>g-at.l^-1 respectively. Fluctuations in the secondary production were greater in the surrounding sea (19.9 to 44.8 mg C.m^-2 d^-1) than at lagoon (6.6 to 15.7 mg C.m^-2 d^-1). Zooplankton community structure was more diverse in the former. The lagoon fauna was characterised by epibenthic forms and zooplankton population was much less compared to the surrounding sea. This depletion in zooplankton may be due to their consumption by the coral reef community when water passes from surrounding sea to lagoon.