Browsing by Author "Naik, H."
Now showing items 1-20 of 57
-
Benthic fluxes in a tropical estuary and their role in the ecosystem
Pratihary, A.K.; Naqvi, S.W.A.; Naik, H.; Thorat, B.R.; Narvenkar, G.; Manjunatha, B.R.; Rao, V.P. (Elsevier, 2009)In-situ measurements of benthic fluxes of oxygen and nutrients were made in the subtidal region of the Mandovi estuary during premonsoon and monsoon seasons to understand the role of sediment-water exchange processes in ... -
Benthic fluxes of methane along the salinity gradient of a tropical monsoonal estuary: Implications for CH4 supersaturation and emission
Araujo, J.; Pratihary, A.K.; Naik, R.; Naik, H.; Naqvi, S.W.A. (Elsevier, 2018)Observations in the Mandovi estuary, a typical tropical monsoonal estuary located on the west coast of India, revealed that waters were perennially supersaturated with CH4, indicating that the estuary could be a significant ... -
Benthic mineralization and nutrient exchange over the inner continental shelf of western India.
Pratihary, A.K.; Naqvi, S.W.A.; Narvenkar, G.; Kurian, S.; Naik, H.; Naik, R.; Manjunatha, B.R. (European Geosciences Union, 2014)The western Indian continental shelf is one of the most productive coastal systems of the world ocean. This system experiences extreme changes in its oxygen regime, being normoxic from November to May and suboxic ... -
Biogeochemical cycling in the low oxygen marine environments
Shenoy, D.M.; Naik, H.; Kurian, S.; Gauns, M.; Ward, B.; Burkill, P.; Smetacek, V. (Elsevier B.V., 2020)Biogeochemistry is the interdisciplinary science of the composition and cycling of chemicalelements. Nitrogen and oxygen are two elements that are essential for living organisms and the sustenance of life on Earth. While ... -
Biogeochemical cycling in the Taiwan Strait
Naik, H.; Chen, C-T.A. (Elsevier, 2008)Based on repeat observations made during 2001-2003 along two transects in the Taiwan Strait this study aims at understanding factors controlling primary productivity with an emphasis on biogeochemical cycling of nitrogen, ... -
Biogeochemistry of methane in a tropical monsoonal estuarine system along the west coast of India
Araujo, J.; Naqvi, S.W.A.; Naik, H.; Naik, R. (Elsevier, 2018)Estuaries are known to be important sources of methane (CH4) to the atmosphere. However, a lack of adequate field studies in understanding the sources/sinks of CH4 in estuaries hampers the global atmospheric budgeting. ... -
Carbon and nitrogen fluxes in the North Indian Ocean
Naqvi, S.W.A.; Naik, H.; DeSouza, W.; Narvekar, P.V.; Paropkari, A.L.; Bange, H.W. (Springer-Verlag, 2010)The land mass that blocks the Indian Ocean in the north at low latitudes profoundly influences the climate, circulation and biogeochemical processes of its northern basins. The asymmetrical distribution of freshwater and ... -
Carbon and nitrogen isotopic composition of suspended particulate organic matter in Zuari Estuary, west coast of India
Bardhan, P.; Karapurkar, S.G.; Shenoy, D.M.; Kurian, S.; Sarkar, A.; Maya, M.V.; Naik, H.; Varik, S.; Naqvi, S.W.A. (Elsevier, 2015)The spatio-temporal variations of the δ13C and δ15N of suspended particulate organic matter (SPOM), along with ancillary chemical and hydrographic parameters, have been examined monthly for one year (October 2010 to September ... -
Coastal versus open-ocean denitrification in the Arabian Sea
Naqvi, S.W.A.; Naik, H.; Pratihary, A.K.; DeSouza, W.; Narvekar, P.V.; Jayakumar, D.A.; Devol, A.H.; Yoshinari, T.; Saino, T. (The European Geosciences Union, 2006)The Arabian Sea contains one of the three major open-ocean denitrification zones in the world. In addition, pelagic denitrification also occurs over the inner and mid-shelf off the west coast of India. The major differences ... -
Cyclone phyan-induced plankton community succession in the coastal waters off Goa, India
Gauns, M.; Kurian, S.; Shenoy, D.M.; Naik, H.; Naqvi, S.W.A. (Current Science Association, 2016)Effects of the cyclonic storm Phyan, which hit the states of Goa and Maharashtra in western India during 9-12 November 2009, on coastal waters were studied. Mixing induced by the cyclone appreciably affected the vertical ... -
Denitrification as the dominant nitrogen loss process in the Arabian Sea
Ward, B.B.; Devol, A.H.; Rich, J.J.; Chang, B.X.; Bulow, S.E.; Naik, H.; Pratihary, A.K.; Jayakumar, A. (Nature Publishing Group, 2009)Primary production in over half of the world’s oceans is limited by fixed nitrogen availability. The main loss term from the fixed nitrogen inventory is the production of dinitrogen gas (N sub(2)) by heterotrophic ... -
Denitrification exceeds anammox as a nitrogen loss pathway in the Arabian Sea oxygen minimum zone
Bulow, S.E.; Rich, J.J.; Naik, H.; Pratihary, A.K.; Ward, B.B. (Elsevier, 2010)The oxygen minimum zones (OMZs) of the world oceans are sites of enhanced anaerobic nitrogen transformations, such that the largest OMZ, the Arabian Sea, is responsible for 30-50% of the oceanic water column fixed N loss. ... -
Denitrification rates and excess nitrogen gas concentrations in the Arabian Sea oxygen deficient zone
Devol, A.H.; Uhlenhopp, A.G.; Naqvi, S.W.A.; Brandes, J.A.; Jayakumar, D.A.; Naik, H.; Gaurin, S.; Codispoti, L.A.; Yoshinari, T. (Elsevier, 2006)Rates of canonical, i.e. heterotrophic, water-column denitrification were measured by sup(15)N incubation techniques at a number of coastal and open ocean stations in the Arabian Sea. Measurements of N2 :Ar gas ratios were ... -
Denitrification rates of culturable bacteria from a coastal location turning temporally hypoxic
Gomes, J.; Khandeparker, R.; Naik, H.; Shenoy, D.M.; Meena, R.M.; Ramaiah, N. (Elsevier B.V., 2020)Nitrate reduction plays a key role in the biogeochemical dynamics and microbial ecology of coastal upwelling systems. Seasonal upwelling in the eastern Arabian Sea entrains nitrate rich waters to the surface, the intense ... -
Dissolved and particulate iron redox speciation during the LOHAFEX fertilization experiment
Laglera, L.M.; Naik, H.; Klaas, C.; Naqvi, S.W.A.; Wolf-Gladrow, D.A.; Tovar-Sanchez, A. (Elsevier, 2022)The redox speciation of iron was determined during the iron fertilization LOHAFEX and for the first time, the chemiluminescence assay of filtered and unfiltered samples was systematically compared.We hypothesize that higher ... -
Dissolved methane in Indian freshwater reservoirs
Narvenkar, G.; Naqvi, S.W.A.; Kurian, S.; Shenoy, D.M.; Pratihary, A.K.; Naik, H.; Patil, S.; Sarkar, A.; Gauns, M. (Springer, 2013)Emission of methane (CH4), a potent greenhouse gas, from tropical reservoirs is of interest because such reservoirs experience conducive conditions for CH4 production through anaerobic microbial activities. It has been ... -
Diversity of culturable nitrate-reducing bacteria from the Arabian Sea oxygen minimum zone
Mulla, A.; Fernandes, G.; Menezes, L.; Meena, R.M.; Naik, H.; Gauns, M.; Damare, S.R. (Elsevier, 2018)The subsurface waters of the northern Arabian Sea display a pronounced oxygen minimum layer associated with high nitrite maxima which provide an ideal niche for organisms that can respire nitrate. Culture-based studies ... -
Enhancement of oceanic nitrous oxide emissions by storms
Bange, H.W.; Naik, H.; Naqvi, S.W.A. (Solas, 2008) -
Impact of physical processes on oxygen loss and production of hydrogen sulphide and methane in a tropical freshwater reservoir
Shenoy, D.M.; Kurian, S.; Shirodkar, G.; Naik, H.; Gauns, M.; Naqvi, S.W.A. (Springer, 2021)Carbon neutrality of tropical reservoirs is a big concern in recent years as some estimates project high methane emission from these reservoirs. While there are studies available on the impact of physical processes ... -
Impact of tropical cyclone on biogeochemistry of the central Arabian Sea
Naik, H.; Naqvi, S.W.A.; Suresh, T.; Narvekar, P.V. (American Geophysical Union, 2008)Remotely sensed data are combined with shipboard measurements to investigate biogeochemical changes caused by a moderate tropical cyclone in the central Arabian Sea in December 1998. The sea surface temperature decreased ...