Studies on the Distribution of Organic Matter and Carbonate Content of Sediments in Mahe Estuary, Northern Kerala

Sediment samples collected from selected stations in the Mahe estuary during the pre- and post-monsoon periods were analysed for their texture, organic matter and carbonate content. It is observed that finer sediments, mainly clayey silt, constitute the major part of the estuarine substratum. Organic matter in the bulk sediments generally follows the distribution pattern of the sediments, i.e., finer the texture greater the organic matter content, whereas the carbonate content shows an inverse relation with the texture. Studies on seasonal variations show that the post-monsoon sediments have higher proportions of organic matter (average: 4.12%) and carbonate (average: 5.23%) content more than those of pre-monsoon periods. No significant relationship between organic matter and carbonate content is observed during pre-monson (r = -0.35) and postmonsoon (r = -0.27) periods.