Elemental composition, distribution and control of biogenic silica in the anthropogenically disturbed and pristine zone inter-tidal sediments of Indian Sundarbans mangrove-estuarine complex. Issue 1 (15th October 2016)

• Record Type: Journal Article
• Authors: Dhame, Shreya; Kumar, Alok; Ramanathan, AL.; Chaudhari, Punarbasu
• Is Part Of: Marine pollution bulletin. Volume 111:Issue 1/2(2016:Oct.)
• Page Start: 68
• Page End: 85
• Publication Date: 2016-10-15
• Subjects: Biogenic silica -- Organic carbon -- Total phosphorus -- Sediment geochemistry -- Sundarbans mangroves; Marine pollution -- Periodicals; Marine Biology -- Periodicals; Water Pollution -- Periodicals; Mer -- Pollution -- Périodiques; Publications périodiques; Pollution des mers; Lutte antipollution; Electronic journals; 363.7394
• DOI: 10.1016/j.marpolbul.2016.07.027
• Languages: English
• ISSNs: 0025-326X

Abstract

Abstract: Spatial distribution and interrelationship among organic nutrients – silica and carbon – and various lithogenic elements were investigated in the surficial sediments of Matla estuary and Core Zone of Indian Sundarbans Reserve Forest using spatial analysis and multivariate statistics. Biogenic silica (BSi), an important parameter for coastal biogeochemisry, was measured using Si-time alkaline leaching method. BSi concentration ranged from 0.01% to 0.85% with higher concentrations in upstream region of Matla estuary and attenuated values towards the bay, seemingly due to changes in hydrodynamics and land use conditions. Spatial distribution of BSi did not exhibit significant correlation with sediment parameters of organic carbon (OC), elemental composition and clay content. However, it showed significant contrasting trends with total phosphorus (TP) and total silica of human influenced Matla estuary sediments as well as the dissolved silica (DSi) of its surface waters. Anthropogenic influence on sediment geochemistry is discernable with the presence of higher concentrations of organic and inorganic elements in Matla estuary than in Core Zone sediments. Spatial variation trends are often challenging to interpret due to multiple sources of input, varying energy and salinity conditions and constant physical, chemical and biological alterations occurring in the environment. Nonetheless, it is certain that anthropogenic activities have a substantial influence on biogeochemical processes of Sundarbans mangrove-estuarine complex and potentially the coastal ocean. Highlights: BSi did not exhibit significant correlation with sediment parameters. Nutirent and elemental variations are influenced by intrinsic characteristics of mangrove. Higher elemental enrichment for Matla estuary sediments than core zone. Mixing, high tidal amplitude and low freshwater flow drives material exchange.