Eleonora M. Fernández , Carla V. Spetter , Mariana Gentile , Diana M. Villagrán , Ana M. Martínez , Natalia S. Buzzi
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引用次数: 0
Abstract
Coastal wetlands, particularly tidal flats, play a crucial role in carbon sequestration and nutrient cycling in temperate environments. This study investigates the biochemical composition of sedimentary organic matter (SOM) in the tidal flats of Puerto Rosales (Bahía Blanca Estuary, Argentina), emphasizing the dual influences of natural processes and anthropogenic activities. Sampling was conducted seasonally (2014–2015) at two sites: ST1, an intertidal zone affected by untreated sewage discharge, and ST2, a supratidal zone dominated by microbial mats. Surface (0–5 mm) and subsurface (5–10 mm) sediment layers were analyzed to assess early diagenetic processes, SOM component and trophic status. Results indicated that the organic carbon (OC) in sediments was predominantly non-biogenic, with proteins as the major component of the labile fraction, influenced by seasonal phytoplankton blooms and urban discharges. While the tidal flat exhibited meso-oligotrophic to eutrophic conditions, refractory material dominated over labile fractions (proteins and carbohydrates). Additionally, distinct spatial and seasonal variations in SOM quality and composition, linked to redox conditions and organic detrital quality were observed.These findings underscore the ecological importance of Puerto Rosales tidal flats as dynamic systems for carbon storage and nutrient recycling. They highlight the need for sustainable management strategies to mitigate anthropogenic pressures and preserve the critical ecosystem functions of these coastal wetlands.
期刊介绍:
Marine Geology is the premier international journal on marine geological processes in the broadest sense. We seek papers that are comprehensive, interdisciplinary and synthetic that will be lasting contributions to the field. Although most papers are based on regional studies, they must demonstrate new findings of international significance. We accept papers on subjects as diverse as seafloor hydrothermal systems, beach dynamics, early diagenesis, microbiological studies in sediments, palaeoclimate studies and geophysical studies of the seabed. We encourage papers that address emerging new fields, for example the influence of anthropogenic processes on coastal/marine geology and coastal/marine geoarchaeology. We insist that the papers are concerned with the marine realm and that they deal with geology: with rocks, sediments, and physical and chemical processes affecting them. Papers should address scientific hypotheses: highly descriptive data compilations or papers that deal only with marine management and risk assessment should be submitted to other journals. Papers on laboratory or modelling studies must demonstrate direct relevance to marine processes or deposits. The primary criteria for acceptance of papers is that the science is of high quality, novel, significant, and of broad international interest.