Ecology of Indian Estuaries: Part 1- Physico-chemical features of water and sediment nutrients of Ashtamudi Estuary

Abstract

Detailed analyses of physico-chemical characteristics and sediment nutrients of Ashtamudi Estuary, Kerala, India. This second biggest estuarine system in Kerala is found to be a zone of severe pollution caused by effluents from a paper mill situated upstream. Seasonal variations in temperature and <i>p</i>H and in the concentrations of dissolved oxygen, salinity, phosphate-P, nitrate-N, nitrite-N and silicate-Si in estuarine waters have been observed at 4 selected stations. A distinct degree of change in relation to the water quality at Kadapuzha was observed. Seasonal variations of organic carbon (OC), total P, total N and total K in the sediments are studied in relation to certain physico-chemical characteristics. Correlations between OC, total P, total N and total K and the grain size reveal that fine grained elements contain more OC and P. Existence of organic phosphate in the sediments of the Ashtamudi Estuary is evidenced by the correlation between OC and P in all the 4 stations. Results of the present study indicate the imperative need to keep the effects of pollution within manageable limits.