Matches in SemOpenAlex for { <https://semopenalex.org/work/W3204111517> ?p ?o ?g. }
- W3204111517 endingPage "102124" @default.
- W3204111517 startingPage "102124" @default.
- W3204111517 abstract "Benthic biogeochemistry and its coupling with pelagic ecology are less understood in tropical than in temperate estuaries, which have significant implications for global carbon and nutrient cycling. In dry season, the Mandovi Estuary of Western India develops a prominent salinity gradient (0–35 psu), and remains nutrient-limited but most productive, which stands in contrast to wet season. To understand the role of benthic exchange in the sustenance of estuarine biogeochemistry and ecosystem, we carried out biogeochemical measurements in the water column and a series of intact-core incubations along the estuarine salinity gradient, during the dry season of 2014. We observed that the lower estuary was nitrogen (N)-limited whereas the middle and upper estuary were phosphorus (P)-limited. The benthic respiration (38.6–82.87 mmol O 2 m −2 d −1 ), organic carbon (C org ) mineralization (34.3–79.8 mmol C m −2 d −1 ) and nutrient exchange rates considerably varied along the salinity gradient. Variability in benthic respiration was apparently controlled by labile C org content and faunal abundance in the sediments. Benthic exchange of NH 4 + and NO x − were mainly controlled by salinity and NO x − of the water column, respectively. Benthic PO 4 3− exchange was predominantly controlled by sedimentary Fe content and bottom water O 2 , whereas benthic SiO 4 4− exchange was primarily controlled by sediment-water SiO 4 4− gradient. Abiotic processes accounted for 37-79% of sediment O 2 consumption (SOC). Benthic metabolism accounted for 34–60% of total community respiration and mineralized 43–145% equivalent of C fixed through primary production (PP). Of dissolved inorganic nitrogen (DIN) efflux (0.67–2.59 mmol m −2 d −1 ), NH 4 + comprised 91% in the lower estuary but NO x − (NO 3 − + NO 2 − ) comprised 97% in the upper estuary, and benthic nitrification apparently determined the dominant N species released from the sediments. Coupled nitrification-denitrification apparently caused the loss of 30–69% of NH 4 + diffusing from the deeper sediments. The estuarine sediments were a net source of DIN and SiO 4 4− , potentially meeting up to 31% of N and 40% of Si demand of the phytoplankton, but acted as a net PO 4 3− sink owing to high sedimentary Fe and normoxia, and tended to buffer the estuarine water PO 4 3− to 0.05–0.19 μM. Benthic PO 4 3− influx (0.006–0.026 mmol m −2 d −1 ) apparently caused the P-limiting condition in the middle and upper estuary. Particularly, the role benthic DIN supply was crucial for the sustenance of estuarine PP as the estuary receives some PO 4 3− from the sea and sufficient SiO 4 4− from the river but not sufficient DIN. The sediments potentially immobilized up to 25% and 20% of riverine DIN and PO 4 3− load, respectively. Overall, the study revealed an efficient benthic carbon recycling and a tight benthic-pelagic coupling in the estuary during the dry season. • Benthic respiration and nutrient fluxes were studied along with the water column biogeochemistry along the salinity gradient of the tropical Mandovi estuary (west coast of India) during the dry season, through intact-core incubations. Normoxia prevailed throughout the estuary while N-limiting condition prevailed in the lower estuary and P-limiting condition in the middle and upper estuary. • Sediment O 2 consumption (SOC) decreased substantially from lower to upper estuary resulting in concomitant decrease in benthic mineralization rate from lower to upper estuary despite increase in sedimentary C org , apparently due to decreasing lability of C org , sediment reactivity and benthic faunal activity towards upstream. Abiotic processes considerably accounted for SOC. The benthic metabolism significantly accounted for the total community respiration. • Of dissolved inorganic nitrogen efflux, NH 4 + comprised the major part in the lower estuary while NO x − (NO 3 − + NO 2 − ) comprised the major part in the upper estuary and benthic nitrification apparently determined the dominant N species released from the sediments. Benthic NH 4 + efflux and benthic NO x − influx were significantly controlled by salinity and water column NO x − , respectively. Coupled nitrification-denitrification apparently caused the loss of a significant percentage of NH 4 + diffusing from the deeper sediments. The estuarine sediment was a net source of DIN. • The estuarine sediment was a net sink of PO 4 3− as benthic PO 4 3− influx occurred throughout the estuary, being geochemically controlled by Fe and O 2 . The sediments also showed PO 4 3− buffering capacity maintaining a low level of PO 4 3− in the water column. Benthic PO 4 3− uptake presumably caused the P-limiting condition in the middle and upper estuary. The sediment was a net source of SiO 4 4− to the water column except in the upper estuary, and benthic SiO 4 4− flux was primarily controlled by sediment-water SiO 4 4− gradient. • Benthic nutrient fluxes were significantly enhanced by benthic faunal activity. Benthic DIN and SiO 4 4− potentially met up to a substantial part of N and Si demand of the estuarine phytoplankton. The estuarine sediments potentially immobilized a significant percentage of the riverine DIN and DIP during the dry season. Overall, the study revealed an efficient benthic carbon recycling and a tight benthic-pelagic coupling in the estuary during the dry season." @default.
- W3204111517 created "2021-10-11" @default.
- W3204111517 creator A5006858568 @default.
- W3204111517 creator A5023743892 @default.
- W3204111517 creator A5057300956 @default.
- W3204111517 creator A5067428183 @default.
- W3204111517 creator A5072779598 @default.
- W3204111517 creator A5077847085 @default.
- W3204111517 creator A5086375505 @default.
- W3204111517 date "2021-11-01" @default.
- W3204111517 modified "2023-10-16" @default.
- W3204111517 title "Benthic exchange along a tropical estuarine salinity gradient during dry season: Biogeochemical and ecological implications" @default.
- W3204111517 cites W1262359895 @default.
- W3204111517 cites W1571975636 @default.
- W3204111517 cites W1964566913 @default.
- W3204111517 cites W1966756487 @default.
- W3204111517 cites W1967733501 @default.
- W3204111517 cites W1968940454 @default.
- W3204111517 cites W1971200458 @default.
- W3204111517 cites W1972765857 @default.
- W3204111517 cites W1973287560 @default.
- W3204111517 cites W1973555596 @default.
- W3204111517 cites W1974573167 @default.
- W3204111517 cites W1974838596 @default.
- W3204111517 cites W1977782445 @default.
- W3204111517 cites W1978284082 @default.
- W3204111517 cites W1978990622 @default.
- W3204111517 cites W1984054894 @default.
- W3204111517 cites W1984607463 @default.
- W3204111517 cites W1986074039 @default.
- W3204111517 cites W1987716850 @default.
- W3204111517 cites W1988909382 @default.
- W3204111517 cites W1988961446 @default.
- W3204111517 cites W1989019885 @default.
- W3204111517 cites W1990611318 @default.
- W3204111517 cites W1992113731 @default.
- W3204111517 cites W1993402651 @default.
- W3204111517 cites W1993523026 @default.
- W3204111517 cites W1998019058 @default.
- W3204111517 cites W1998245106 @default.
- W3204111517 cites W1998875591 @default.
- W3204111517 cites W2004260817 @default.
- W3204111517 cites W2006686440 @default.
- W3204111517 cites W2006932244 @default.
- W3204111517 cites W2007541921 @default.
- W3204111517 cites W2008118539 @default.
- W3204111517 cites W2008772238 @default.
- W3204111517 cites W2009940717 @default.
- W3204111517 cites W2010021578 @default.
- W3204111517 cites W2011311779 @default.
- W3204111517 cites W2011358020 @default.
- W3204111517 cites W2016094557 @default.
- W3204111517 cites W2018557354 @default.
- W3204111517 cites W2018923328 @default.
- W3204111517 cites W2019278350 @default.
- W3204111517 cites W2020851749 @default.
- W3204111517 cites W2022691835 @default.
- W3204111517 cites W2026840978 @default.
- W3204111517 cites W2026874696 @default.
- W3204111517 cites W2028517731 @default.
- W3204111517 cites W2030125283 @default.
- W3204111517 cites W2030567089 @default.
- W3204111517 cites W2031204927 @default.
- W3204111517 cites W2031503593 @default.
- W3204111517 cites W2032046036 @default.
- W3204111517 cites W2032488786 @default.
- W3204111517 cites W2035503922 @default.
- W3204111517 cites W2038445638 @default.
- W3204111517 cites W2039275800 @default.
- W3204111517 cites W2040235107 @default.
- W3204111517 cites W2040823492 @default.
- W3204111517 cites W2044838978 @default.
- W3204111517 cites W2051831140 @default.
- W3204111517 cites W2054607151 @default.
- W3204111517 cites W2062334220 @default.
- W3204111517 cites W2062623604 @default.
- W3204111517 cites W2063434212 @default.
- W3204111517 cites W2063557800 @default.
- W3204111517 cites W2066386749 @default.
- W3204111517 cites W2066559785 @default.
- W3204111517 cites W2067315335 @default.
- W3204111517 cites W2067492024 @default.
- W3204111517 cites W2070722963 @default.
- W3204111517 cites W2074273597 @default.
- W3204111517 cites W2084723569 @default.
- W3204111517 cites W2086611603 @default.
- W3204111517 cites W2087047419 @default.
- W3204111517 cites W2087649457 @default.
- W3204111517 cites W2088925435 @default.
- W3204111517 cites W2089986323 @default.
- W3204111517 cites W2090157291 @default.
- W3204111517 cites W2091000835 @default.
- W3204111517 cites W2091422286 @default.
- W3204111517 cites W2094923814 @default.
- W3204111517 cites W2097767248 @default.
- W3204111517 cites W2100764093 @default.
- W3204111517 cites W2102840125 @default.
- W3204111517 cites W2104122538 @default.