Investigation of Submarine Groundwater Discharge using Thermal Satellite and Radon mapping along the East Coast of the Tamil Nadu and Pondicherry Region, India
Open Access
- 23 May 2021
- journal article
- Published by IOR Press in International Journal of Civil, Environmental and Agricultural Engineering
Abstract
Submarine groundwater discharge (SGD) demarcated as a significant component of hydrological cycle found to discharge greater volumes of terrestrial fresh and recirculated seawater to the ocean associated with chemical constituents (nutrients, metals, and organic compounds) aided by downward hydraulic gradient and sediment-water exchange. Delineating SGD is of primal significance due to the transport of nutrients and contaminants due to domestic, industrial, and agricultural practices that influence the coastal water quality, ecosystems, and geochemical cycles. An attempt has been made to demarcate the SGD using thermal infrared images and radon-222 (222Rn) isotope. Thermal infrared images processed from LANDSAT-8 data suggest prominent freshwater fluxes with higher temperature anomalies noted in Cuddalore and Nagapattinam districts, and lower temperature noted along northern and southern parts of the study area suggest saline/recirculated discharge. Groundwater samples were collected along the coastal regions to analyze Radon and Physico-chemical constituents. Radon in groundwater ranges between 127.39 Bq m-3 and 2643.41 Bq m-3 with an average of 767.80 Bq m-3. Calculated SGD fluxes range between -1.0 to 26.5 with an average of 10.32 m day-1. Comparison of the thermal infrared image with physio-chemical parameters and Radon suggest fresh, terrestrial SGD fluxes confined to the central parts of the study area and lower fluxes observed along with the northern and southern parts of the study area advocate impact due to seawater intrusion and recirculated seawater influence.Keywords
This publication has 37 references indexed in Scilit:
- Approximation of submarine groundwater discharge and allied nutrient fluxes to the Bay of Bengal, India using nutrient mass balanceEnvironmental Earth Sciences, 2021
- Submarine Groundwater Discharge from an Urban Estuary to Southeastern Bay of Bengal, India: Revealed by Trace Element FluxesArchives of Environmental Contamination and Toxicology, 2020
- Effect of land use and groundwater flow path on submarine groundwater discharge nutrient fluxJournal of Hydrology: Regional Studies, 2017
- Global river nutrient export: A scenario analysis of past and future trendsGlobal Biogeochemical Cycles, 2010
- Submarine Groundwater Discharge (SGD) and Associated Nutrient Fluxes to the Coastal OceanPublished by Springer Science and Business Media LLC ,2010
- The Effect of Submarine Groundwater Discharge on the OceanAnnual Review of Marine Science, 2010
- Submarine groundwater discharge revealed by 228Ra distribution in the upper Atlantic OceanNature Geoscience, 2008
- Radon as a tracer of submarine groundwater discharge into a boat basin in Donnalucata, SicilyContinental Shelf Research, 2006
- Nutrient inputs to the coastal ocean through submarine groundwater discharge: controls and potential impactJournal of Hydrology, 2004
- Nutrient Changes in the Mississippi River and System Responses on the Adjacent Continental ShelfEstuaries, 1996