N:P stoichiometry and transparent exopolymeric particles buffer ecological impacts of nutrients in the Ganga River: a mesocosm study. Issue 5 (28th May 2018)

• Record Type: Journal Article
• Authors: Pandey, Jitendra; Pandey, Usha; Singh, Anand V.; Jaiswal, Deepa; Siddiqui, Ekabal; Verma, Kavita
• Is Part Of: Chemistry and ecology. Volume 34:Issue 5(2018)
• Page Start: 422
• Page End: 438
• Publication Date: 2018-05-28
• Subjects: Diatoms -- Ganga River -- mesocosm -- N:P stoichiometry -- transparent exopolymeric particles; Pollution -- Environmental aspects -- Periodicals; Ecology -- Periodicals; 577.2
• DOI: 10.1080/02757540.2018.1444035
• Languages: English
• ISSNs: 0275-7540

Abstract

ABSTRACT: We investigated the possible drivers of the N:P stoichiometric shift and its relationship with micro-algal production of transparent exopolymeric particles (TEP) along a 35 km gradient of the Ganga River. The objective was to evaluate if the trade-off between N:P stoichiometry and production of TEP helps in maintaining water quality of the river. Mesocosm experiments were conducted to examine N:P-TEP linkages and its role in turbidity removal. In situ measurements did not show Si to be a limiting nutrient (N:Si < 1.3). The TEP production increased with decreasing N:P ratio and peaked at N:P::6:1 with dominance of Aulacosira granulata and Fragilaria intermedia. Settling efficiency, turbidity removal and sedimentation of TEP, biogenic silica (BSi) and biomass all increased with decreasing N:P ratio proportionately to the amount of TEP produced in the mesocosm. The study demonstrates that trade-off between N:P stoichiometry and the production of TEP generates feedback to buffer the ecological impacts of nutrient pollution.