Indian Journal of Geo Marine Sciences Vol. 47 (01), January 2018, pp. 193-199 Pre-monsoon and monsoon seasonal changes in physico-chemical characteristics of Chinnamuttom and Colachel harbour waters, Southeast coast of India Nithya, P1., B. Dhanalakshmi1, .P. Santhanam2* & S. Dinesh Kumar2 1PG and Research Department of Zoology, Nirmala College for Women (Autonomous), Coimbatore-641018, Tamil Nadu, India 2Marine Planktonology & Aquaculture Lab., Department of Marine Science, School of Marine Sciences, Bharathidasan University, Tiruchirappalli-620 024, Tamil Nadu, India. * [E-mail:
[email protected],
[email protected]] Received 02 November 2015 ; revised 17 November 2016 º Seasonal variations in physico-chemical parameters such as atmospheric temperature, surface water temperature ( C), -1 pH, salinity (psu) and dissolved oxygen (mg L ) in Chinnamuttom and Colachel harbours waters were 26-33 (S1), 26-32.3 (S2); 23.6-26.8 (S1), 23.2 -26.4 (S2); 7.44 -8.12 (S1), 7.46 -8.11 (S2); 27.1 -33.5 (S1), 27-33 (S2); 3.8-5.3 (S1), 4.1-5.6(S2) respectively. Ranges of inorganic nutrients (mg L-1) viz., phosphate, nitrite, nitrate, reactive silicate and ammonia were 0.59-1.96 (S1); 0.56-1.93 (S2); 0.79-1.77 (S1), 0.63 -1.74 (S2); 0.097-0.4 (S1), 0.095-0.38 (S2); 0.65-0.77 (S1), 0.64-0.77 (S2); 0.01-0.03(S1), 0.014-0.032(S2) respectively. Physico-chemical parameters of harbour waters have obtained important seasonal and spatial variations. Due to increased harbour activities in both the selected study sites over the last decades, there has been a lot of anthropogenic stress on the aquatic ecosystem.