A.T.RAMCHANDRA NAIKAYESHA FARHEEN2023-12-272023-12-272022https://krishikosh.egranth.ac.in/handle/1/5810204637Seasonal variations of physico-chemical properties of selected stations of Mangaluru coast and accumulation of heavy metals concentration in selected species of cephalopods was studied over a period of eight months. Water temperature, pH, salinity, dissolved oxygen and the biological oxygen demand were in the range of 27.1 to 31.9oC, 7.22 to 8.13, 28.43 to 31.85 PSU, 6.00 to 7.74 mg/l and 0.68 to 1.84 mg/l respectively. The ammonia, nitrite, nitrate and phosphate were in the range of 1.71 to 4.98, 1.52 to 3.94, 10.65 to 12.87 and 0.44 to 2.86 μg-at./l respectively. Sediment pH, Electrical conductivity, total carbon, total nitrogen and total phosphorus recorded were 7.11 to 8.88, 3.23 to 17.3 S/m, 0.11 to 4.75%, 0.11 to 4.01% and 0.55 to 4.94% respectively. Heavy metal concentration of Copper (143.08 μg/g) was found significantly higher in all the tissues followed by Zinc (91.67 μg/g), Nickle (58.54 μg/g), Lead (6.78 μg/g) and Cadmium (2.04 μg/g). From this study, it was found that Zn, Pb, Ni, Cd and Cu concentrations in the tissues were lower than the maximum limit recommended by the EU, Codex, USFDA. According to the Metal Pollution Index (MPI), the ink-sac of cephalopod indicated high-range contamination, while the head and tentacle showed medium contamination levels but mantle recorded lowest in all the organs. The heavy metals concentration in different organs of cephalopods showed the trend of maximum to minimum in the fashion of ink-sac > head > tentacles > arm > mantle in the cephalopods viz octopus > cuttlefish > squid respectively.EnglishThesis