The high altitude valley of Kashmir abounds in a vast array of freshwater bodies of lotic as well as lentic nature. Amongst these, lakes play an important role in biodiversity of this region. The present study on Wular Lake, Kashmir was undertaken from March, 2007 to February, 2008 to study abundance and distribution of phytoplankton and their correlation with physico-chemical conditions of water. A total of 64 phytoplankton belonging to bacillariophyceae, chlorophyceae, cyanophyceae and euglenophyceae were identified. Phytoplankton in general, showed two growth periods, one in spring and other in winter. A clear dominance of bacillariophyceae over chlorophyceae, cyanophyceae and euglenophyceae was observed throughout the study period. Navicula spp. with population density of 118 no./ml was recorded to be the most abundant species amongst bacillariophyceae at the selected site. Chlorophyceae formed the second most dominant group of phytoplankton with Chlorella spp. (112 no./ml) as the most abundant species. Osillatoria spp. with population density of 119 no./ml was found to be the most abundant amongst cyanophyceae. Euglenophyceae formed the least represented group of phytoplankton with peak population in spring. Statistically, bacillariophyceae and euglenophyceae showed significant negative correlation (r = -0.855 and r = -0.177) with water temperature, while cyanophyceae showed significant positive correlation (r = 0.745). Chlorophyceae showed nonsignificant positive correlation (r = 0.325) with water temperature at the selected site. Shannon-Wiener diversity index (H′) value (1.672) was recorded for cyanophyceae, while the highest evenness (J′) value (0.8872) was recorded for euglenophyceae. The value of Berger-Parker index of dominance (0.1859) was highest for bacillariophyceae. Canonical correspondance analysis (CCA) was also carried out to analyze the relationship between the physico-chemical parameters and the phytoplankton. It showed that the most important factors affecting phytoplankton distribution are water temperature, CO 2 , chloride, transparency, TDS, alkalinity and dissolved oxygen.

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The river Ganga basin accommodates large scale of agricultural activities, where large quantities of pesticides are applied. To assess the biological impact of pesticide residues that are continuously entering in the water body, biomarkers are common approach in bio-monitoring study as early warning signals to pollutants. In the present study qualitative and quantitative analyses of gill and liver histopathological and the biochemical parameters were determined in Rita rita and Cyprinus carpio. The difference in the histopathology and oxidative stress responses emphasize the response of selected fishes to the presence of contaminants in the water. Sloughing of lamellar epithelium and their disruption, dilated vessels, lamellar fusion, smooth muscle hypertrophy in the gill and necrosis, Vacuolation in hepatocytes, inflammation and distorted arterial walls were seen in the liver. The biochemical parameters were the main contributors to discriminate the changes in the fish physiology. In conclusion, the gill and liver histopathological responses, although not reflecting specific contaminants, but can be used as biomarkers of environmental contamination.

The dramatic and spontaneous exodus of live Clinostomum complanatum progenetic metacercaria from the gill slits of the dying intermediate host, Trichogaster fasciatus is reported. Basic water parameter tests for dissolved oxygen, pH and temperature revealed slightly lower level of dissolved oxygen in tank water used for water change. To the best of our knowledge, it is the first report of a digenean metacercariae, en mass leaving their intermediate host, upon its death in search of an alternative host to support their survival and help in continuing their life cycle.

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