The diversity, abundance and community structure of mesozooplankton from the hydrographically differing mangrove habitats in Cochin, Kerala (India), were investigated. Eleven zooplankton groups were ...identified, with calanoid copepods (62%) comprising the predominant population, followed by crustacean nauplii (22%) and mysids (12%). Nitrogen limiting (N: P ratio 5.13 ± 7.03) with a mixo‐mesohaline salinity (8.96 ± 3 psu) and relatively low temperatures (30.28 ± 0.9 °C) was a characteristic feature of the study zones. Non‐metric multidimensional scaling based on Bray–Curtis similarity (PRIMER) analysis revealed there was little variation in the mesozooplankton structure among sampling sites (stress 0.05; ANOSIM test Global R:0.325). BEST analysis indicated that temperature and salinity exhibited the best correlation (ρ = 0.701) with fauna. The results of this study indicated a severe reduction in zooplankton abundance, biomass and diversity. It is clear that the zooplankton communities are depleting, along with the mangrove vegetation, because of the shallowness and unsuitable environmental conditions of the water bodies attributable to anthropogenic stresses.
The effects of sub-lethal concentrations of copper and the ameliorating capacity of vitamin C on the humoral and biochemical parameters in the teleost fish, Anabas testudineus, were investigated. The ...96 h LC 50 value of copper for A. testudineus was determined by Probit method and was found to be 1.74 mg/L. The blood of fish from two sub-lethal concentrations along with vitamin supplemented media and control medium, were analysed. The haemoglobin (Hb), haematocrit (Hct), erythrocyte count (RBC), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), and mean corpuscular haemoglobin concentration (MCHC) were reduced (p > 0.0001) in copper exposed fish compared to the control. The leucocyte (WBC) count increased (p < 0.0001) with dose and duration. Immature and amitotic RBCs, hypoxia, hypochromia, and crenation were observed in highest nominal concentrations and last exposures. The plasma glucose, cortisol, GOT (Glutamate oxalate transaminase), GPT (Glutamate pyruvate transaminase), ALP (Alkaline phosphatase) and LDH (lactate dehydrogenase) increased (p < 0.0001), and serum protein decreased. However, on day 28, the Hb, RBC count, MCH, MCHC, and the oxygen carrying capacity increased, and glucose, cortisol and LDH decreased, markedly. The administration of vitamin C improved the blood parameters, illustrating its prophylactic capacity to overwhelm the trace metal stress. doi:10.14456/WJST.2014.78
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