Variability of organic carbon matter and nitrogen deposits in a carbonate platform of mangroves
Keywords:Climate change, δ13C, δ15N, Mangrove forest sediment, organic carbon
Mangroves are usually characterized by their high potential for long-term sequestration of organic carbon. Sediment accretion by these valuable habitats increased their capability of organic carbon sequestration. In this study, we aimed to examine the organic carbon sequestration of mangrove expansion (Avicennia germinans) in southern Iran. Different variables have been investigated in the sampled sediments, including δ13C, δ 15N, TOC, TN, and C/N ratio. Our findings indicated the significant variation of measured variables in several top intervals, reflecting the existence of autochthonous and allochthonous organic substances. Our data showed that the minority of δ13C values are lower than -23% in the S3 site, suggesting that mangrove litter is a critical input OC (δ13C, -28 to -30%). On the other hand, the significantly higher value of δ13C (-14 to -23%) indicates that phytoplankton and possibly local microphytobenthos are the primary sources of organic materials inputs. Moreover, site S4 presents the highest mean value of C/N, TN, and δ15N, which can be justified because of its proximity to the estuary and supply of organic matters imported from algal sources. The substantial role of mangrove forests depositing organic carbon should be investigated in the global carbon cycle.
Bouillon S., Dahdouh-Guebas F., Rao A.V.V.S., Koedam N., Dehairs F. 2003. Sources of organic carbon in mangrove sediments: variability and possible ecological implications. Hydrobiologia 495:33-39.
Breithaupt J. L., Smoak J.M., Smith T. J. Sanders C.J., Hoare A. 2012. Organic carbon burial rates in mangrove sediments: Strengtheningthe global budget. Global Biogeochemical Cycles 26(3): GB3011.
Briggs R.A., Ruttenberg K.C., Glazer B.T., Ricardo A.E. 2013.Constraining Sources of Organic Matter to Tropical Coastal Sediments: Consideration of Nontraditional End members. Aquatic Geochemistry 19:543–563.
Donato D.C., Kauffman J.B., Murdiyarso D., Kurnianto S., Stidham M., Kanninen M. 2011. Mangroves among the most carbon-rich forests in the tropics. Nature Geoscience 4(5):293-297.
Duarte C. M., Losada I. J., Hendriks I. E., Mazarrasa I., Marbà N. 2013. The role of coastal plant communities for climate change mitigation and adaptation. Nature Climate Change 3(11):961–968.
Ellison J 2004. Vulnerability of Fiji's mangroves and associated coral
reefs to climate change. Prepared for the World Wildlife Fund.
University of Tasmania, Launceston.
Gilman E.L., Ellison J., Duke, N.C., Field, C. 2008. Threats to mangroves from 9 climate change and adaptation options: a review. Aquatic Botany 89:237-250
Hopkinson C.S., Cai W., Hu A. 2012. Carbon sequestration in wetland dominated coastal systems - a global sink of rapidly diminishing magnitude. Current Opinions in Environmental Sustainability 4:1-9.
Kennedy H., Gacia E., Kenndy D.P., Papadimitriou S., Duarte C. M. 2004. Organic carbon sources to SE Asian coastal sediments. Estuary Coastal and Shelf Science 60:59-68.
Kristensen E., Bouillon S., Dittmar T., Marchand C. 2008. Organic carbon dynamics in mangrove ecosystems: a review. Aquatic Botany 89(2):201–219.
Kristensen E., Suraswadi P. 2002. Carbon, nitrogen and phosphorus dynamics in creek water of a Southeast Asian mangrove forest. Hydrobiologia 474:197–211.
Malhi Y., Grace J. 2000. Tropical forests and atmospheric carbon dioxide. Trends in Ecology and Evolution 15:332- 337.
Marchand C., Lallier-Vergès E., Baltzer F., 2003. The composition of sedimentary organic matter in relation to the dynamic features of a mangrove-fringed coast in
French Guiana Estuary. Estuarine, Coastal and Shelf Science 56: 119–130
Papadimitriou S., Kennedy H., Kennedy D.P., Duarte C.M., Marbà N., 2005. Sources of organic matter in seagrass-colonized sediments: a stable isotope study of the silt and clay fraction from Posidonia oceanica meadows in the western Mediterranean. Organic Geochemistry 36(6):949-961.
Petrosian H., Kar A., Ashrafi S., Feghhi J. 2016. Investigating Environmental Factors for Locating Mangrove Ex-situ Conservation Zones Using GIS Spatial Techniques and the Logistic Regression Algorithm in Mangrove Forests in Iran. Polish Journal of Environmental Studies 25(5):2097–2106.
Ranjan R.K., Routh J., Ramanathan A.L. 2010. Bulk organic matter characteristics in the Pichavaram mangrove estuarine complex, south-eastern India. Applied Geochemistry 25(8):1176–1186.
Sanders C.J., Eyre B.D., Santos I.R., Machado W., Luiz-Silva W., Smoak J.M., Breithaupt J.L., Ketterer M.E., Sanders L., Marotta H., Silva-Filho E. 2014. Elevated rates of organic carbon, nitrogen,and phosphorus accumulation in a highly impacted mangrove wetland. Geophysical Research Letters 41: 2475–2480.
Schile L.M., Kauffman J.B., Crooks S., Fourqurean J.W., Glavan J., Megonigal J.P., 2016. Limits on carbon sequestration in arid blue carbon ecosystems. Ecological Applications 27(3): 859–874.
Smith S.V., Hollibaugh J.T. 1993. Coastal metabolism and the oceanic carbon balance. Reviews of Geophysics 31:75-89.
Soto-Jimenez M.F., Paez-Osuna F., Ruiz-Fernandez. A.C. 2003. Organic matter and nutrients in an altered subtropical marsh system, Chiricahueto, NW Mexico. Environmental Geology 43:913-921.
Thimdee W., Deein G., Sangrungruang C., Nishioka J., Matsunaga K. 2003. Sources and fate of organic matter in Khung Krabaen Bay (Thailand) as traced by delta C-13 and C/N atomic ratios. Wetlands 23:729-738.
Toosi N.B., Soffianian A.R., Fakheran S., Pourmanafi S., Ginzler C., Waser L.T. 2019. Comparing different classification algorithms for monitoring mangrove cover changes in southern Iran. Global Ecology and Conservation 19:e00662.
Williamson G.J., Boggs G.S., Bowman D.M. 2011. Late 20th century mangrove encroachment in the coastal Australian monsoon tropics parallels the regional increase in woody biomass. Regional Environmental Change 11(1):19-27.
Yang J., Gao J., Cheung A., Liu B., Schwendenmann L., Costello M.J., 2013.
Vegetation and sediment characteristics in an expanding mangrove forest in New
Zealand. Estuar. Estuary. Estuarine, Coastal and Shelf Science134, 11–18.
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