Record Details

Sources and distribution of organic matter in thirty five tropical estuaries along the west coast of India-a preliminary assessment

DRS at CSIR-National Institute of Oceanography

View Archive Info
 
 
Field Value
 
Title Sources and distribution of organic matter in thirty five tropical estuaries along the west coast of India-a preliminary assessment
 
Creator Pradhan, U.K.
Wu, Y.
Shirodkar, P.V.
Zhang, J.
Zhang, G.
 
Subject organic matter
sediment
biomarker
continental shelf
 
Description Studies characterizing the sources of organic matter (OM) to the west coast of India (WCI) and its continental shelf are limited. This study examined sedimentary OM in 35 estuaries along the WCI using molecular biomarkers (lignin phenol), elemental ratio (C/N), and stable carbon isotope (delta13C) values. Multivariate statistical techniques, such as cluster analysis, identified similar sedimentary chemical properties among the estuaries and their distribution patterns highlight the strong control of geographical provenance on sedimentary OM composition from south to north along the WCI. Results of an end-member mixing model reveal that terrigenous sources (C3 plants, C4 plants, and soil) contribute ~80% of estuarine OM, with the remaining 20% derived from marine sources (marine plankton and estuarine macrophytes). In the estuaries of large rivers, such as the Narmada and Sabarmati rivers, C4 plants and soil OM were found to be the dominant contributors of OM, which is likely the result of an abundance of C4 vegetation and agriculture in their catchment areas. High OC (organic carbon content) of sediments (0.5-5%) from the WCI estuaries indicates that large amounts of OM are present in the sediments. The sources of OM (plant and soil) shift substantially throughout the study area, corresponding to changes in land use patterns along the Western Ghats. Sediments with low nitrogen contents (C/N > 15-20) and degraded lignin ((Ad/Al)V ¼ 0.4-0.6 and DHBA/V ¼ 0.16-0.34) were observed in all estuaries, indicating humification and/or degradation of OM originating from terrestrial plants (bio-degradation) and soil (de-mineralization). The collective results of this study illustrate the benefits of using biomarkers (lignin phenols) along with C/N and delta13C values for evaluating land use changes and the impacts of land use changes on aquatic ecosystems.
 
Date 2014-11-28T07:02:25Z
2014-11-28T07:02:25Z
2014
 
Type Journal Article
 
Identifier Estuarine, Coastal and Shelf Science, vol.151; 2014; 21-33
http://drs.nio.org/drs/handle/2264/4640
 
Language en
 
Rights An edited version of this paper was published by Elsevier. Copyright [2014] Elsevier
 
Publisher Elsevier