Journal articles: 'Estuarine embayment'

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Cotovicz, L. C., B. A. Knoppers, N. Brandini, S. J. Costa Santos, and G. Abril. "A large CO<sub>2</sub> sink enhanced by eutrophication in a tropical coastal embayment (Guanabara Bay, Rio de Janeiro, Brazil)." Biogeosciences Discussions 12, no. 6 (March 23, 2015): 4671–720. http://dx.doi.org/10.5194/bgd-12-4671-2015.

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Abstract. In contrast to its small surface area, the coastal zone plays a disproportionate role in the global carbon cycle. Carbon production, transformation, emission and burial rates at the land–ocean interface are still poorly known, especially in tropical regions. Surface water pCO2 and ancillary parameters were monitored during nine field campaigns between April 2013 and April 2014 in Guanabara Bay, a tropical eutrophic to hypertrophic semi-enclosed estuarine embayment surrounded by the city of Rio de Janeiro, SE-Brazil. Water pCO2 varied between 22 and 3715 ppmv in the Bay showing spatial, diurnal and seasonal trends that mirrored those of dissolved oxygen (DO) and Chlorophyll a (Chl a). Marked pCO2 undersaturation was prevalent in the shallow, confined and thermally stratified waters of the upper bay, whereas pCO2 oversaturation was restricted to sites close to the small river mouths and small sewage channels, which covered only 10% of the bay's area. Substantial daily variations in pCO2 (up to 395 ppmv between dawn and dusk) were also registered and could be integrated temporally and spatially for the establishment of net diurnal, seasonal and annual CO2 fluxes. In contrast to other estuaries worldwide, Guanabara Bay behaved as a net sink of atmospheric CO2, a property enhanced by the concomitant effects of strong radiation intensity, thermal stratification, and high availability of nutrients, which promotes phytoplankton development and net autotrophy. In the inner part of the bay, the calculated annual CO2 sink (−19.6 mol C m2 yr-1) matched the organic carbon burial in the sediments reported in the literature. The carbon sink and autotrophy of Guanabara Bay was driven by planktonic primary production promoted by eutrophication, and by its typology of marine embayment lacking the classical extended estuarine mixing zone, in contrast to river-dominated estuarine systems, which are generally net heterotrophic and CO2 emitters. Our results show that global CO2 budgetary assertions still lack information on tropical estuarine embayments and lagoons, which are affected by thermal stratification and eutrophication and behave specifically with respect to atmospheric CO2.

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Zampatti, Brenton P., Christopher M. Bice, and Paul R. Jennings. "Temporal variability in fish assemblage structure and recruitment in a freshwater-deprived estuary: The Coorong, Australia." Marine and Freshwater Research 61, no. 11 (2010): 1298. http://dx.doi.org/10.1071/mf10024.

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River regulation can diminish freshwater flows to estuaries and compromise estuarine functionality. Understanding biotic responses to altered flow regimes is imperative to effectively manage aquatic ecosystems. The present study investigated temporal variation in fish assemblage structure and the recruitment of catadromous fish in the Coorong estuary at the terminus of the Murray River, in south-eastern Australia. Over the three-year study period, freshwater inflows to the estuary diminished and ultimately ceased, disconnecting freshwater and estuarine environments. It was hypothesised that these conditions would lead to (1) increases in estuarine salinities and concomitant changes in fish assemblage structure and abundance, and (2) decreased recruitment of catadromous fish. As freshwater inflow decreased, salinities immediately downstream of a series of tidal barrages increased from brackish to marine–hypersaline, species richness and diversity decreased, freshwater and diadromous species became less abundant and assemblages were increasingly characterised by marine species. Furthermore, the abundance of young-of-year catadromous fish decreased dramatically. Excessive regulation of freshwater inflows is resulting in the Coorong estuary resembling a marine embayment, leading to a loss in species diversity. We suggest, however, that even small volumes of freshwater may promote diversity in estuarine fish assemblages and some recruitment of catadromous species.

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Atilla, Nazan. "Meiofaunal Colonization of Artificial Substrates in an Estuarine Embayment." Marine Ecology 21, no. 1 (April 2000): 69–83. http://dx.doi.org/10.1046/j.1439-0485.2000.00700.x.

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Garcon, Veronique C., Keith D. Stolzenbach, and Donald M. Anderson. "Tidal Flushing of an Estuarine Embayment Subject to Recurrent Dinoflagellate Blooms." Estuaries 9, no. 3 (September 1986): 179. http://dx.doi.org/10.2307/1352129.

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Stevens, Craig. "Short-term dispersion and turbulence in a complex-shaped estuarine embayment." Continental Shelf Research 30, no. 5 (March 2010): 393–402. http://dx.doi.org/10.1016/j.csr.2009.12.011.

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Stevens, Craig L. "Turbulence in an estuarine embayment: Observations from Beatrix Bay, New Zealand." Journal of Geophysical Research: Oceans 108, no. C2 (February 2003): n/a. http://dx.doi.org/10.1029/2001jc001221.

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Mörs, Th. "Biostratigraphy and paleoecology of continental Tertiary vertebrate faunas in the Lower Rhine Embayment (NW-Germany)." Netherlands Journal of Geosciences - Geologie en Mijnbouw 81, no. 2 (August 2002): 177–83. http://dx.doi.org/10.1017/s0016774600022411.

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AbstractThis paper discusses the faunal content, the mammal biostratigraphy, and the environmental ecology of three important continental Tertiary vertebrate faunas from the Lower Rhine Embayment. The sites investigated are Rott (MP 30, Late Oligocene), Hambach 6C (MN 5, Middle Miocene), Frechen and Hambach 11 (both MN 16, Late Pliocene). Comparative analysis of the entire faunas shows the assemblages to exhibit many conformities in their general composition, presumably resulting from their preference for wet lowlands. It appears that very similar environmental conditions for vertebrates reoccurred during at least 20 Ma although the sites are located in a tectonically active region with high subsidence rates. Differences in the faunal composition are partly due to local differences in the depositional environment of the sites: lake deposits at the margin of the embayment (Rott), coal swamp and estuarine conditions in the centre of the embayment (Hambach 6C), and flood plain environments with small rivulets (Frechen and Hambach 11). The composition of the faunal assemblages (diversity and taxonomy) also documents faunal turnovers with extinctions and immigrations (Oligocene/Miocene and postMiddle Miocene), as a result of changing climate conditions.Additional vertebrate faunal data were retrieved from two new assemblages collected from younger strata at the Hambach mine (Hambach 11C and 14). They are important for the understanding of the Plio-Pleistocene transition in the southern part of the Lower Rhine Embayment and for correlating depositional sequences in the Dutch/German borderland.

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Tessier, Bernadette, Isabelle Billeaud, and Patrick Lesueur. "Stratigraphic organisation of a composite macrotidal wedge: the Holocene sedimentary infilling of the Mont-Saint-Michel Bay (NW France)." Bulletin de la Société Géologique de France 181, no. 2 (March 1, 2010): 99–113. http://dx.doi.org/10.2113/gssgfbull.181.2.99.

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Abstract The Mont-Saint-Michel Bay (NW France) is a composite macrotidal environment that was filled up in the course of the Holocene transgression and sea-level highstand. Three main sub-environments constitute the present-day landscape of the bay: 1) a wide embayment with extensive mud to sandflats in the south, 2) a sandy to muddy channel-and-shoal estuarine system in the east, 3) a wave-dominated sandy coast composed of beach and dune barrier in the north. The Holocene infill of this composite macrotidal basin has been studied thanks to a set of vibrocores and VHR seismic data. The main results are summarized as follows: the TST is composed by a low-energy aggradational unit in the axis of the estuarine valley, and by high-energy sediment bodies (tidal dunes and banks) outside the valley; the HST (post 6500 yr B.P.) constitutes the main component of the infill. In the north, it is characterised by an aggradational unit made of back-barrier tidal lagoonal infill successions. In the embayment, it is represented by an aggradational unit composed of tidal-flat deposits. In the estuarine axis, the HST is constituted by a sand-dominated tidal channel-and-shoal belt. The rate of the Holocene sea-level rise appears to be the main factor of control of the infill architecture of the Mont-Saint-Michel Bay since the most significant change occurred around 6500 yr B.P. when the transgression slowed down. The interaction between hydrodynamic agents and sediment supply exerts as well a key control, especially during the late Holocene, when transgression is slow. The impact of climate changes is recorded in the infill during this period. The rocky substrate hypsometry should be considered also as a major forcing parameter as it determines the potential of preservation of the infill in relation with the depth of ravinement by tidal currents.

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Pollard, M., and AN Hodgson. "Mytilus galloprovincialis (Mollusca: Bivalvia) in a warm-temperate South African estuarine embayment." African Journal of Aquatic Science 41, no. 1 (January 28, 2016): 57–65. http://dx.doi.org/10.2989/16085914.2015.1119670.

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10

Logan, Brendan, Kathryn H. Taffs, and Laura Cunningham. "Applying paleolimnological techniques in estuaries: a cautionary case study from Moreton Bay, Australia." Marine and Freshwater Research 61, no. 9 (2010): 1039. http://dx.doi.org/10.1071/mf09277.

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Paleoecological techniques are useful tools to identify restoration targets and natural variability for natural resource management programs. However, despite recent advances, caution is required when employing paleoecological techniques in estuaries, due to their dynamic nature relative to lake environments where these techniques were pioneered. This study used a novel combination of chronological, diatom, geochemical and isotopic data to assess the effectiveness of using these techniques in estuaries, and to develop an understanding of environmental changes within Moreton Bay, an open estuarine environment in subtropical east Australia. Results indicated mixed success, with 210Pb results indicating only background unsupported 210Pb levels, 14C results indicating sediment deposition from mixed sources, no diatom preservation and inconsistencies between geochemical and isotope proxies. Evidence did exist that the Moreton Bay sediments have been derived from different sources over the past 10 000 years. However, isotope records were not able to identify the likely sources of these sediments. Problems with diatom preservation were most probably due to the high salinity and temperatures associated with subtropical open embayment estuaries. Future studies attempting to identify environmental histories of estuaries should incorporate river-influenced locations rather than marine-dominated sites to ensure better diatom preservation and more definitive geochemical signals.

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Hodgson, Alan N., Frances Smith, Peter Smith, and Louw Claassens. "Macrofauna associated with intertidal mussel beds in the Knysna estuarine embayment, South Africa." African Zoology 56, no. 1 (January 2, 2021): 44–57. http://dx.doi.org/10.1080/15627020.2020.1848457.

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12

Rheuban, J. E., S. Williamson, J. E. Costa, D. M. Glover, R. W. Jakuba, D. C. McCorkle, C. Neill, T. Williams, and S. C. Doney. "Spatial and temporal trends in summertime climate and water quality indicators in the coastal embayments of Buzzards Bay, Massachusetts." Biogeosciences 13, no. 1 (January 15, 2016): 253–65. http://dx.doi.org/10.5194/bg-13-253-2016.

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Abstract. Degradation of coastal ecosystems by eutrophication is largely defined by nitrogen loading from land via surface water and groundwater flows. However, indicators of water quality are highly variable due to a myriad of other drivers, including temperature and precipitation. To evaluate these drivers, we examined spatial and temporal trends in a 22-year record of summer water quality data from 122 stations in 17 embayments within Buzzards Bay, MA (USA), collected through a citizen science monitoring program managed by Buzzards Bay Coalition. To identify spatial patterns across Buzzards Bay's embayments, we used a principle component and factor analysis and found that rotated factor loadings indicated little correlation between inorganic nutrients and organic matter or chlorophyll a (Chl a) concentration. Factor scores showed that embayment geomorphology in addition to nutrient loading was a strong driver of water quality, where embayments with surface water inputs showed larger biological impacts than embayments dominated by groundwater influx. A linear regression analysis of annual summertime water quality indicators over time revealed that from 1992 to 2013, most embayments (15 of 17) exhibited an increase in temperature (mean rate of 0.082 ± 0.025 (SD) °C yr−1) and Chl a (mean rate of 0.0171 ± 0.0088 log10 (Chl a; mg m−3) yr−1, equivalent to a 4.0 % increase per year). However, only seven embayments exhibited an increase in total nitrogen (TN) concentration (mean rate 0.32 ± 0.47 (SD) µM yr−1). Average summertime log10(TN) and log10(Chl a) were correlated with an indication that the yield of Chl a per unit total nitrogen increased with time suggesting the estuarine response to TN may have changed because of other stressors such as warming, altered precipitation patterns, or changing light levels. These findings affirm that nitrogen loading and physical aspects of embayments are essential in explaining the observed ecosystem response. However, climate-related stressors may also need to be considered by managers because increased temperature and precipitation may worsen water quality and partially offset benefits achieved by reducing nitrogen loading.

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13

Rheuban, J. E., S. C. Williamson, J. E. Costa, D. M. Glover, R. W. Jakuba, D. C. McCorkle, C. Neill, T. Williams, and S. C. Doney. "Spatial and temporal trends in summertime climate and water quality indicators in the coastal embayments of Buzzards Bay, Massachusetts." Biogeosciences Discussions 12, no. 15 (August 14, 2015): 13159–92. http://dx.doi.org/10.5194/bgd-12-13159-2015.

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Abstract. Degradation of coastal ecosystems by eutrophication is largely defined by nitrogen loading from land via surface and groundwater flows. However, indicators of water quality are highly variable due to a myriad of other drivers, including temperature and precipitation. To evaluate these drivers, we examined spatial and temporal trends in a 22 year record of summer water quality data from 122 stations in 17 embayments within Buzzards Bay, MA (USA), collected through a citizen science monitoring program managed by Buzzards Bay Coalition. To identify spatial patterns across Buzzards Bay's embayments, we used a principle component and factor analysis and found that rotated factor loadings indicated little correlation between inorganic nutrients and organic matter and chlorophyll a (Chl a) concentration. Factor scores showed that embayment geomorphology in addition to nutrient loading was a strong driver of water quality, where embayments with surface water inputs showed larger biological impacts than embayments dominated by groundwater influx. A linear regression analysis of annual summertime water quality indicators over time revealed that from 1992 to 2013, most embayments (15 of 17) exhibited an increase in temperature (mean rate of 0.082 ± 0.025 (SD) °C yr−1) and Chl a (mean rate of 0.0171 ± 0.0088 log10 (Chl a; mg m−3) yr−1, equivalent to a 4.0 % increase per year). However, only 7 embayments exhibited an increase in total nitrogen (TN) concentration (mean rate 0.32 ± 0.47 (SD) μM yr−1). Average summertime log10 (TN) and log10 (Chl a) were correlated with an indication that yield of Chl a per unit total nitrogen increased with time suggesting the estuarine response to TN may have changed because of other stressors such as warming, altered precipitation patterns, or changing light levels. These findings affirm that nitrogen loading and physical aspects of embayments are essential in explaining observed ecosystem response. However, climate-related stressors may also need to be considered by managers because increased temperature and precipitation may worsen water quality and partially offset benefits achieved by reducing nitrogen loading.

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14

Munsch, SH, JR Cordell, and JD Toft. "Effects of seawall armoring on juvenile Pacific salmon diets in an urban estuarine embayment." Marine Ecology Progress Series 535 (September 15, 2015): 213–29. http://dx.doi.org/10.3354/meps11403.

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Chua, H., P. H. F. Yu, and M. W. L. Cheung. "Sediment Oxygen Demand and Nutrient Release in An Eutrophic Estuarine Embayment in Hong Kong." Journal of Lake Sciences 10, s1 (1998): 275–82. http://dx.doi.org/10.18307/1998.sup30.

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RICHARDS, P. C. "An estuarine facies model for the Middle Jurassic Sleipner Formation: Beryl Embayment, North Sea." Journal of the Geological Society 148, no. 3 (May 1991): 459–71. http://dx.doi.org/10.1144/gsjgs.148.3.0459.

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Simpson, Stuart L., Louisa Rochford, and Gavin F. Birch. "Geochemical influences on metal partitioning in contaminated estuarine sediments." Marine and Freshwater Research 53, no. 1 (2002): 9. http://dx.doi.org/10.1071/mf01058.

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Stormwater runoff has resulted in heavy metal contamination throughout much of the Port Jackson estuary, Sydney, Australia. Metal partitioning was investigated in the benthic estuarine sediments of Iron Cove, an off-channel embayment of Port Jackson. Contamination was greatest near the stormwater canal, where sediments were anoxic and contained high concentrations of sulfide in the porewater. Away from the canal a layer of non-cohesive, sub-oxic surficial sediment containing high dissolved iron was found overlaying a more cohesive substratum. At all sites, porewater Cd, Cu, Ni, Pb and Zn were <2.5 g L–1, and negligible metal release was observed upon sediment resuspension. According to water quality guidelines, the ecological risk posed by dissolved metals from the Iron Cove sediments is low. Estimated fluxes of Cd, Cu, Ni, Pb and Zn from the sediments were calculated to be <0.2 mol m–2 day–1. The rapid oxidation then hydrolysis of iron(II) in porewaters caused a drop in pH and the formation of iron hydroxide precipitate. These processes may affect dissolved metal concentrations; hence, oxidation of samples must be avoided during sampling and extraction procedures. Sediment-bound zinc was the metal most easily mobilized.

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Rosa, Leonardo Cruz, and Carlos Emilio Bemvenuti. "Effects of the burrowing crab Chasmagnathus granulata (Dana) on meiofauna of estuarine intertidal habitats of Patos Lagoon, Southern Brazil." Brazilian Archives of Biology and Technology 48, no. 2 (March 2005): 267–74. http://dx.doi.org/10.1590/s1516-89132005000200014.

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This study aimed to evaluate the effects of the burrowing crab Chasmagnathus granulata on meiofauna at three intertidal habitats across a tidal exposure gradient (i.e., an emerged salt marsh, an emerged mudflat and a submerged mudflat) in an estuarine embayment of Patos Lagoon, Southern Brazil. Meiofauna community was dominated by nematodes and ostracods, following by copepods and turbellarians. Densities of all studied organisms varied significantly among habitats. Highest values were observed in submerged mudflat while lower in salt marsh. Nematodes were unaffected by crab in either habitat, whereas ostracod, copepod and turbellarian densities were significantly lower in disturbed than control areas in both mudflat habitats. Any meiofaunal group was affected in salt marsh, probably due to a less intense disturbance. The results showed that the burrowing crab C. granulata could play an important role on meiofauna community structure in estuarine intertidal habitats of Patos Lagoon, because crab disturbance seemed to affect mainly surface populations, especially in mudflat. However, the meiofauna response to crab disturbance was variable among habitats depending of the intensity and the frequency of the disturbance.

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Pillay, D., GM Branch, and AT Forbes. "Habitat change in an estuarine embayment: anthropogenic influences and a regime shift in biotic interactions." Marine Ecology Progress Series 370 (October 28, 2008): 19–31. http://dx.doi.org/10.3354/meps07631.

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Everett, BI, and ST Fennessy. "Assessment of recreational boat-angling in a large estuarine embayment in KwaZulu-Natal, South Africa." African Journal of Marine Science 29, no. 3 (December 2007): 411–22. http://dx.doi.org/10.2989/ajms.2007.29.3.9.339.

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Park, Seok S., Kenneth F. Najjar, and Christopher G. Uchrin. "A water quality management model for the Lakes Bay estuarine embayment 2: Hydrodynamic tidal model." Journal of Environmental Science and Health . Part A: Environmental Science and Engineering and Toxicology 30, no. 5 (June 1995): 1025–38. http://dx.doi.org/10.1080/10934529509376247.

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Ortega, Ileana, Christopher Fonseca Ibeiro, Lucas Santos Rodrigues, Marcos Alaniz Rodrigues, and Luiz Felipe Cestari Dumont. "Habitat use in different life and moulting stages of Callinectes sapidus (Decapoda, Portunidae) in South Brazilian estuarine and marine environments." Journal of the Marine Biological Association of the United Kingdom 100, no. 1 (December 17, 2019): 79–91. http://dx.doi.org/10.1017/s0025315419001085.

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AbstractThe blue crab Callinectes sapidus is an important ecological and commercial species. It plays a fundamental role in the structure and function of coastal benthic food webs, with global catches of ~74,357 tons. This is the most exploited portunid species in Brazil. However, few studies about the ecology and population dynamics of C. sapidus have been published. This study aimed to analyse the preferred areas for the spatial distribution of juveniles and moulting individuals of C. sapidus in shallow areas of the Patos Lagoon estuary and the adjacent marine reproductive area, and their relation to water and sediment characteristics. Juveniles and moulting individuals preferred the embayment of the upper estuary, where the sediments are finer, with higher contents of organic matter and the presence of submerged vegetation. There was also a temporal variability in the abundance of juvenile size classes, with two marked increments of smaller individuals: (1) in late spring and summer and (2) in winter, indicating two recruitment peaks. Unusual environmental conditions in the summer of the first year, with an increase of fine sediments and organic matter, combined with low salinities in the adjacent marine area, allowed recruitment of individuals there. We suggest better attention to the embayment around the Marinheiros Island (considered here as upper estuary) for management and protection measures due to the overlapping of recruitment preferences of the blue crab, pink shrimp and fish species in this area.

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Sumpton, Wayne D., Bill Sawynok, and Neil Carstens. "Localised movement of snapper (Pagrus auratus, Sparidae) in a large subtropical marine embayment." Marine and Freshwater Research 54, no. 8 (2003): 923. http://dx.doi.org/10.1071/mf02119.

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Snapper were tagged with dart and anchor tags in order to determine movement and the contribution of juveniles inhabiting estuarine areas to the offshore adult population. Laboratory experiments showed that loss of anchor tags was greater than dart tags, although this was not reflected in the results of field trials. A total of 6572 individuals were tagged in field experiments, of which 509 (7.7%) were recaptured. Only four of over 2500 fish tagged and released in Moreton Bay were recaptured in waters outside the bay, suggesting the bay is not an important source of recruits to the offshore fishery. However, problems associated with tag loss and mortality meant that the actual contribution of juveniles to the offshore fisheries remained unclear. Most snapper movements were localised; only ~1% of movements exceeded 100 km. Movements of snapper were mainly directed northward against the prevailing direction of the East Australian Current. Snapper were considered to be a suitable species for marine reserve protection owing to their relatively localised movement patterns.

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Bibi, Riaz, Hee Yoon Kang, Dongyoung Kim, Jaebin Jang, Changseong Kim, Goutam K. Kundu, and Chang-Keun Kang. "Biochemical Composition of Seston Reflecting the Physiological Status and Community Composition of Phytoplankton in a Temperate Coastal Embayment of Korea." Water 13, no. 22 (November 13, 2021): 3221. http://dx.doi.org/10.3390/w13223221.

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The biochemical composition of seston along a salinity gradient were examined in the low-turbidity, temperate, estuarine embayment, Gwangyang Bay in Korea. Seasonal variations in sestonic protein (PRT), carbohydrate (CHO), and lipid (LIP) concentrations were analyzed to assess the effects of physiological status and taxonomic composition of phytoplankton. The concentrations of biochemical compounds displayed a close relationship with chlorophyll a (Chla). PRT:CHO ratios were high (>1.0) in the estuarine channel in warmer months and in whole bay in February, indicating a N-replete condition for phytoplankton growth. High CHO:LIP ratios (>2.5) in the saline deep-bay area during the warmer months (>2.0) emphasized the importance of temperature and photoperiod over nutritional conditions. The low POC:Chla (<200), molar C:N (~7) ratios, and biopolymeric carbon concentrations coupled with high primary productivity indicated a low detrital contribution to the particulate organic matter pool. Diatom dominance throughout the year contributed to consistently high carbohydrate concentrations. Furthermore, generalized additive models highlighted that phytoplankton community (i.e., size) structure may serve as an important descriptor of sestonic biochemical composition. Collectively, our results suggest that physiological and taxonomic features of phytoplankton play prominent roles in determining the biochemical composition of seston, supporting the fact that the ecosystem processes in Gwangyang Bay are largely based on phytoplankton dynamics.

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Cotovicz Jr., L. C., B. A. Knoppers, N. Brandini, S. J. Costa Santos, and G. Abril. "A strong CO<sub>2</sub> sink enhanced by eutrophication in a tropical coastal embayment (Guanabara Bay, Rio de Janeiro, Brazil)." Biogeosciences 12, no. 20 (October 27, 2015): 6125–46. http://dx.doi.org/10.5194/bg-12-6125-2015.

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Abstract. In contrast to its small surface area, the coastal zone plays a disproportionate role in the global carbon cycle. Carbon production, transformation, emission and burial rates at the land–ocean interface are significant at the global scale but still poorly known, especially in tropical regions. Surface water pCO2 and ancillary parameters were monitored during nine field campaigns between April 2013 and April 2014 in Guanabara Bay, a tropical eutrophic to hypertrophic semi-enclosed estuarine embayment surrounded by the city of Rio de Janeiro, southeast Brazil. Water pCO2 varied between 22 and 3715 ppmv in the bay, showing spatial, diurnal and seasonal trends that mirrored those of dissolved oxygen (DO) and chlorophyll a (Chl a). Marked pCO2 undersaturation was prevalent in the shallow, confined and thermally stratified waters of the upper bay, whereas pCO2 oversaturation was restricted to sites close to the small river mouths and small sewage channels, which covered only 10 % of the bay's area. Substantial daily variations in pCO2 (up to 395 ppmv between dawn and dusk) were also registered and could be integrated temporally and spatially for the establishment of net diurnal, seasonal and annual CO2 fluxes. In contrast to other estuaries worldwide, Guanabara Bay behaved as a net sink of atmospheric CO2, a property enhanced by the concomitant effects of strong radiation intensity, thermal stratification, and high availability of nutrients, which promotes phytoplankton development and net autotrophy. The calculated CO2 fluxes for Guanabara Bay ranged between −9.6 and −18.3 mol C m−2 yr−1, of the same order of magnitude as the organic carbon burial and organic carbon inputs from the watershed. The positive and high net community production (52.1 mol C m−2 yr−1) confirms the high carbon production in the bay. This autotrophic metabolism is apparently enhanced by eutrophication. Our results show that global CO2 budgetary assertions still lack information on tropical, marine-dominated estuarine systems, which are affected by thermal stratification and eutrophication and behave specifically with respect to atmospheric CO2.

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Radloff, J., AN Hodgson, and L. Claassens. "Settlement of the invasive mussel Mytilus galloprovincialis in a warm temperate estuarine embayment in South Africa." African Journal of Aquatic Science 46, no. 2 (February 11, 2021): 206–14. http://dx.doi.org/10.2989/16085914.2020.1842170.

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Jones, Nicole L., and Stephen G. Monismith. "The Influence of Whitecapping Waves on the Vertical Structure of Turbulence in a Shallow Estuarine Embayment." Journal of Physical Oceanography 38, no. 7 (July 1, 2008): 1563–80. http://dx.doi.org/10.1175/2007jpo3766.1.

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Abstract The vertical distribution of the turbulent kinetic energy dissipation rate was measured using an array of four acoustic Doppler velocimeters in the shallow embayment of Grizzly Bay, San Francisco Bay, California. Owing to the combination of wind and tide forcing in this shallow system, the surface and bottom boundary layers overlapped. Whitecapping waves were generated for a significant spectral peak steepness greater than 0.05 or above a wind speed of 3 m s−1. Under conditions of whitecapping waves, the turbulent kinetic energy dissipation rate in the upper portion of the water column was greatly enhanced, relative to the predictions of wind stress wall-layer theory. Instead, the dissipation followed a modified deep-water breaking-wave scaling. Near the bed (bottom 10% of the water column), the dissipation measurements were either equal to or less than that predicted by wall-layer theory. Stratification due to concentration gradients in suspended sediment was identified as the likely cause for these periods of production–dissipation imbalance close to the bed. During 50% of the well-mixed conditions experienced in the month-long experiment, whitecapping waves provided the dominant source of turbulent kinetic energy over 90% or more of the water column.

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Coates-Marnane, J., J. Olley, J. Burton, and A. Grinham. "The impact of a high magnitude flood on metal pollution in a shallow subtropical estuarine embayment." Science of The Total Environment 569-570 (November 2016): 716–31. http://dx.doi.org/10.1016/j.scitotenv.2016.06.193.

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Byun, Do-Seong, Xiao Hua Wang, Deirdre E. Hart, and Yang-Ki Cho. "Modeling the effect of freshwater inflows on the development of spring blooms in an estuarine embayment." Estuarine, Coastal and Shelf Science 65, no. 1-2 (October 2005): 351–60. http://dx.doi.org/10.1016/j.ecss.2005.06.012.

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Najjar, Kenneth F., Seok S. Park, and Christopher G. Uchrin. "A water quality management model for the Lakes Bay estuarine embayment 1: Receiving water quality model." Journal of Environmental Science and Health . Part A: Environmental Science and Engineering and Toxicology 30, no. 5 (June 1995): 1001–23. http://dx.doi.org/10.1080/10934529509376246.

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Meng, Ling, Qianguo Xing, Xuelu Gao, Diansheng Ji, Fanzhu Qu, Xiaoqing Wang, and Ling Ji. "Effects of an Episodic Storm-Induced Flooding Event on the Biogeochemistry of a Shallow, Highly Turbid, Semi-Enclosed Embayment (Laizhou Bay, Bohai Sea)." Sustainability 15, no. 1 (December 28, 2022): 563. http://dx.doi.org/10.3390/su15010563.

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Episodic storm-induced flooding is becoming more frequent with a warming climate, which may alter the biogeochemical properties and conditions of estuaries. However, the effects of such extreme events on semi-enclosed bay ecosystems have not been fully investigated because of the difficulty in collecting in situ samples. To address this issue, a comparative study was carried out to understand the biogeochemical changes in Laizhou Bay, a shallow, highly turbid, semi-enclosed bay, by coupling satellite data and surface water samplings collected during an episodic flooding event (August 2018) and during a non-flooding period (August 2017). The results showed that the 2018 Shouguang flood delivered large amounts of suspended solids, phosphorus, and organic matter-enriched terrigenous materials into Laizhou Bay and enhanced the offshore expansion of the low-salinity seawater plume and associated nutrient fronts. Water total suspended solid (TSS) particle and chlorophyll a (Chl-a) concentrations increased by 23.79 g/m3 and 0.63 mg/m3, respectively, on average in the freshwater mixing water plume around the Mi River. Episodic flooding is a crucial driver which temporally dominates the spatial patterns of water biogeochemistry. These results are essential to anticipate the ecosystem response of estuarine regions to the high episodic freshwater flow associated with the increasing storms.

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Izegaegbe, JI, L. Vivier, and HMM Mzimela. "Macrobenthic community structure of the Mhlathuze Estuary, a permanently open estuarine embayment in KwaZulu-Natal, South Africa." African Journal of Aquatic Science 45, no. 1-2 (April 2, 2020): 95–107. http://dx.doi.org/10.2989/16085914.2020.1719818.

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Byun, Do-Seong, Xiao Hua Wang, Marco Zavatarelli, and Yang-Ki Cho. "Effects of resuspended sediments and vertical mixing on phytoplankton spring bloom dynamics in a tidal estuarine embayment." Journal of Marine Systems 67, no. 1-2 (August 2007): 102–18. http://dx.doi.org/10.1016/j.jmarsys.2006.10.003.

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Parham, Peter R., Stanley R. Riggs, Stephen J. Culver, David J. Mallinson, and John F. Wehmiller. "Quaternary depositional patterns and sea-level fluctuations, Northeastern North Carolina." Quaternary Research 67, no. 1 (January 2007): 83–99. http://dx.doi.org/10.1016/j.yqres.2006.07.003.

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AbstractA detailed record of late Quaternary sea-level oscillations is preserved within the upper 45 m of deposits along an eight km transect across Croatan Sound, a drowned tributary of the Roanoke/Albemarle drainage system, northeastern North Carolina. Drill-hole and seismic data reveal nine relatively complete sequences filling an antecedent valley comprised of discontinuous middle and early Pleistocene deposits. On interfluves, lithologically similar marine deposits of different sequences occur stacked in vertical succession and separated by ravinement surfaces. Within the paleo-drainage, marine deposits are separated by fluvial and/or estuarine sediments deposited during periods of lowered sea level. Foraminiferal and molluscan fossil assemblages indicate that marine facies were deposited in a shallow-marine embayment with open connection to shelf waters. Each sequence modifies or truncates portions of the preceding sequence or sequences. Sequence boundaries are the product of a combination of fluvial, estuarine, and marine erosional processes. Stratigraphic and age analyses constrain the ages of sequences to late Marine Isotope Stage (MIS) 6 and younger (∼ 140 ka to present), indicating multiple sea-level oscillations during this interval. Elevations of highstand deposits associated with late MIS 5 and MIS 3 imply that sea level was either similar to present during those times, or that the region may have been influenced by glacio-isostatic uplift and subsidence.

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Padmakumar, Vidya, and Murugan S. "Mangrove ecology and species distribution along the Gorai Creek of Mumbai coast, Maharashtra, India." International Journal of Forest, Animal And Fisheries Research 6, no. 4 (2022): 22–26. http://dx.doi.org/10.22161/ijfaf.6.4.4.

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The extensive mangrove forest of Gorai Creek, Mumbai coast, has recently seen substantial deterioration. The results of a study on mangrove diversity conducted in Gorai Creek on the Mumbai coast from June 2017 to May 2018 are presented here. During the course of the study, twelve species of mangroves from five families and eight genera were identified in each of the three study locations along the creek. Avicennia marina accounted for 13.44% of the Gorai creek marshes, confirming its predominance. Sonneratia alba, Avicennia officinalis, Rhizophora apiculata, Bruguiera cylindrica, Kandelia candel, and Acanthus ilicifolius are among the mangrove species found in the estuarine embayment, with other species strewn around. A diverse range of species, including endangered migratory birds and herpetofauna, can be found in these mangrove environments. Mangroves have been observed to have narrowed in density with time, and it is critical to begin conservation efforts as speedily as humanly possible.

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Suárez-Morales, Eduardo, and Iván A. Castellanos-Osorio. "A new species of Monstrilla (Copepoda, Monstrilloida) from the plankton of a large coastal system of the northwestern Caribbean with a key to species." ZooKeys 876 (September 25, 2019): 111–23. http://dx.doi.org/10.3897/zookeys.876.38400.

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The genus Monstrilla Dana, 1849 is the most diverse of the copepod order Monstrilloida. Monstrilloid copepods are endoparasites of benthic polychaetes and molluscs; adult individuals are free-living, non-feeding reproductive forms that briefly become part of the zooplankton community, where they are occasionally captured by plankton nets. Monstrilloid copepods are frequently found during routine plankton samplings of coastal and estuarine habitats, but they are rarely found in large numbers. The western sector of the Caribbean Sea is known to harbor a diverse monstrilloid fauna. The analysis of zooplankton samples obtained during nine years from Chetumal Bay, a large embayment of the Mexican Caribbean coast, yielded a male monstrilloid that was found to represent a new species. It is herein described following upgraded standards and compared with its congeners. A key to males and females of the Monstrilla species known from the northwestern Caribbean is also provided.

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McEwan, James, Albert J. Gabric, and Peter R. F. Bell. "Water quality and phytoplankton dynamics in Moreton Bay, south-eastern Queensland. I. Field survey and satellite data." Marine and Freshwater Research 49, no. 3 (1998): 215. http://dx.doi.org/10.1071/mf95096.

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The water quality of Moreton Bay, a sub-tropical estuarine embayment in south-eastern Queensland, was monitored over a 2-year period. Surveys in situ and ground-truthed satellite imagery were used to describe the temporal and spatial variability in water-quality indicators and the level of eutrophication. Strong east–west gradients in chlorophyll α and water clarity were found. During the study period fluvial discharges, which all enter on the western littoral, were below their long-term averages, and nutrient loading to the bay was dominated by point-source wastewater discharges along the western boundary. The data suggest that although the impact of nutrient loads on the bay’s eastern side is mitigated by tidal intrusion of oceanic water, the western areas are already degraded and can be considered mesotrophic to eutrophic. This part of the bay may deteriorate further with the projected future population expansion in the bay’s catchment.

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Zhang, Yuexia, Jun Yu, Zhibing Jiang, Qin Wang, and Hui Wang. "Variations of summer phytoplankton community related to environmental factors in a macro-tidal estuarine embayment, Hangzhou Bay, China." Journal of Ocean University of China 14, no. 6 (November 7, 2015): 1025–33. http://dx.doi.org/10.1007/s11802-015-2483-6.

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Silva, P. G., J. L. Giner-Robles, J. Elez, E. Roquero, M. A. Rodríguez-Pascua, R. Pérez-López, A. Martínez-Graña, T. Bardají, and M. A. Perucha. "Historical earthquakes in the Lower Segura basin (SE Spain): geological and archaeological evidence from pre-roman to modern times." Zeitschrift für Geomorphologie, Supplementary Issues 62, no. 2 (October 1, 2019): 247–69. http://dx.doi.org/10.1127/zfg_suppl/2018/0492.

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This paper deals with the analysis of ancient and historical earthquakes in the Lower Segura Depression (SE Spain) at the northern end of the Eastern Betic Cordillera Shear Zone (EBSZ), which is defined within the area by the Lower Segura blind-thrust fault. The work summarizes and updates the existing information on the building and environmental damage dispersed throughout several historical documents, as well as the new historical and archaeological research on the area. The analyses performed consider the evolving paleogeography of the old estuarine zone defined by Ibero-Roman "Sinus ilicitanus" and the ancient prograding delta of the Segura River over the marshes. Topographic data from old descriptions of the zone together with the analysis of the geometry of the medieval irrigation system in the growing delta from pre-Roman to modern (18th century) times, allow the paleogeographic evolution of the zone, until the eventual artificial infilling of the old embayment, to be outlined. Several strong earth- quakes (Intensity ≥ VIII EMS-98) occurred in the area during different historical times. Building damage for the different events was variable depending on the number of settlements (and increasing population) within the ancient embayment. Maximum Intensity X during the most recent earthquake (AD 1829 Torrevieja) mainly occurred over old lands reclaimed in the 18 th century. In addition, dominant earthquake secondary effects (EEEs) were caused by liquefaction processes. This study analyzes the dimensions and distribution of these EEEs for the two main earthquakes in the zone during the years AD 1048 and AD 1829 using the ESI-07 intensity scale. The results draw important inferences on the role of ancient paleo-geography in seismic hazard data from past earthquakes.

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Hodgson, AN, L. Claassens, and S. Kankondi. "Shell morphometrics and growth rate of the invasive bivalve mollusc Mytilus galloprovincialis in the Knysna estuarine embayment, South Africa." African Journal of Aquatic Science 43, no. 4 (November 18, 2018): 367–74. http://dx.doi.org/10.2989/16085914.2018.1539647.

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Anderson, DM, and KD Stolzenbach. "Selective retention of two dinoflagellates in a well-mixed estuarine embayment: the importance of diel vertical migration and surface avoidance." Marine Ecology Progress Series 25 (1985): 39–50. http://dx.doi.org/10.3354/meps025039.

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Clarke, PJ, and WG Allaway. "Litterfall in Casuarina glauca Coastal Wetland Forests." Australian Journal of Botany 44, no. 4 (1996): 373. http://dx.doi.org/10.1071/bt9960373.

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Litterfall was measured over 3 years at two sites in coastal wetland forests dominated by Casuarina glauca Sieb. ex Spreng. in New South Wales. One site was in an incised river valley adjacent to the Hawkesbury River estuary, and the other site was in an open embayment adjacent to Botany Bay. Branchlets were the major litter component, followed by stems and infructescences. Significant year to year variation in branchlet fall correlated with storm events in one year. Overall, no significant differences in annual total litterfall were detected among sites and, averaged over all sites and years, the mean annual litterfall was 848 g m-2. This suggests that coastal wetland forests dominated by C. glauca have some of the highest recorded annual litterfall rates for Australian temperate and subtropical forests. A flood event in the river valley site removed about 75% of the standing litter accumulated on the forest floor prior to flooding (1244 g m-2). This suggests that accumulated organic matter and nutrients can be directly transported to estuarine ecosystems. Under non-flood conditions, however, these forests appear to act as organic matter and nutrient sinks.

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Watts, Robyn J., and Michael S. Johnson. "Estuaries, lagoons and enclosed embayments: habitats that enhance population subdivision of inshore fishes." Marine and Freshwater Research 55, no. 7 (2004): 641. http://dx.doi.org/10.1071/mf04051.

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Several studies have suggested that estuaries, lagoons and enclosed embayments may offer special opportunities for local subdivision in marine species. We used data from published papers and unpublished theses to examine the effect of such water bodies on allozyme differentiation of seven species of inshore fishes in Western Australia. We included species that differ in their dispersal, and hence their intrinsic potential for gene flow. Over large distances, subdivision was generally greater among estuarine populations than among conspecific marine populations collected over similar distances. Over small distances, paired marine and estuarine samples were generally more divergent than pairs of marine samples separated by similar distances. For species with a low capability for dispersal, estuaries appear to add to the high levels of genetic subdivision that commonly result from other factors. Under special circumstances estuaries may also provide opportunities for genetic divergence in species with a high capability of dispersal that are rarely subdivided at a large geographical scale. These observations indicate that estuaries can increase the genetic subdivision of populations of inshore fishes, and that species that use both marine and estuarine habitats are likely to have greater genetic subdivision than those that are restricted to marine habitats.

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Dickson, Sarah, Joseph Carlin, Nicole Bonuso, and Matthew E. Kirby. "Documenting the Evolution of a Southern California Coastal Lagoon during the Late Holocene." Coasts 2, no. 2 (May 24, 2022): 102–24. http://dx.doi.org/10.3390/coasts2020007.

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Coastal wetlands are declining globally, and although wetland restoration looks to offset these losses, its success relies on anticipating environmental response to external forces. The purpose of this study is to investigate the sedimentological record of Los Peñasquitos Lagoon to determine the processes that drive environmental transitions in a Southern California coastal wetland. For this project, we analyze three sediment cores from the wetland for grain size, total organic matter, and shell assemblages to reconstruct environmental change over the past ~4000 years. From the results, we find that the lagoon was initially an open embayment that persisted for >2000 years; however, at ~1000 cal yrs BP, a short-lived wet climatic period triggered a fluvial deltaic progradation at the head of the lagoon. As the wet period ended and drier conditions returned, the delta began to retreat, and the lagoon infilled as the estuarine mouth bar was permanently established. The permanent establishment of the mouth bar resulted in a transition to a marsh-dominated environment throughout the wetland. Ultimately, these environmental transitions were driven by climate variability, although evidence of human impacts was observed more recently in the record. Therefore, future restoration efforts must consider both natural climatic variability and anthropogenic influences if they intend to sustain coastal wetlands.

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Ryves, David B., Annemarie L. Clarke, Peter G. Appleby, Susanne L. Amsinck, Erik Jeppesen, Frank Landkildehus, and N. John Anderson. "Reconstructing the salinity and environment of the Limfjord and Vejlerne Nature Reserve, Denmark, using a diatom model for brackish lakes and fjords." Canadian Journal of Fisheries and Aquatic Sciences 61, no. 10 (October 1, 2004): 1988–2006. http://dx.doi.org/10.1139/f04-127.

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Diatoms in surface sediments from a data set of 27 brackish lakes and nine fjords in Jutland, Denmark (range 0.2 31 g·L1 total dissolved solids (TDS)), were analysed using multivariate methods to determine response to measured parameters (depth, total phosphorus (TP), total nitrogen (TN), TN/TP, salinity, water body type). Water body type, salinity, depth and TP together explained 25.3% of the variation in the diatom data and were all independently significant predictors. A diatomsalinity model (r2jack = 0.887, root mean square error of prediction = 0.246 log salinity, g·L1) was developed from the 36 sample training set and applied to fossil diatom assemblages in three sediment cores from the east Vejlerne wetland, Denmark, a nature reserve created after the damming of an embayment of the polyhaline Limfjord (~26 g·L1 TDS) in the late 19th century. The diatominferred salinity reconstructions reflect the known salinity history of the Limfjord and the freshwatersubsaline Vejlerne lakes, and appear sensitive to documented North Sea storms in the 16th and 17th centuries, which had major impacts on the brackish Limfjord herring fishery. Diatomsalinity models may be useful tools in long-term studies of coastal and estuarine areas to test hypotheses concerning aquatic resources and ecological, hydrographic, and cultural change.

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Garces, E. "In situ growth rate and distribution of the ichthyotoxic dinoflagellate Gyrodinium corsicum Paulmier in an estuarine embayment (Alfacs Bay, NW Mediterranean Sea)." Journal of Plankton Research 21, no. 10 (October 1, 1999): 1977–91. http://dx.doi.org/10.1093/plankt/21.10.1977.

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Burchard, Hans, Götz Flöser, Joanna V. Staneva, Thomas H. Badewien, and Rolf Riethmüller. "Impact of Density Gradients on Net Sediment Transport into the Wadden Sea." Journal of Physical Oceanography 38, no. 3 (March 1, 2008): 566–87. http://dx.doi.org/10.1175/2007jpo3796.1.

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Abstract This study tests the hypothesis that horizontal density gradients have the potential to significantly contribute to the accumulation of suspended particulate matter (SPM) in the Wadden Sea. It is shown by means of long-term observations at various positions in the Wadden Sea of the German Bight that the water in the inner regions of the Wadden Sea is typically about 0.5–1.0 kg m−3 less dense than the North Sea water. During winter this occurs mostly because of freshwater runoff and net precipitation; during summer it occurs mostly because of differential heating. It is demonstrated with idealized one-dimensional water column model simulations that the interaction of such small horizontal density gradients with tidal currents generates net onshore SPM fluxes. Major mechanisms for this are tidal straining, estuarine circulation, and tidal mixing asymmetries. Three-dimensional model simulations in a semienclosed Wadden Sea embayment with periodic tidal forcing show that SPM with sufficiently high settling velocity (ws = 10−3 m s−1) is accumulating in the Wadden Sea Bight because of density gradients. This is proven through a comparative model simulation in which the dynamic effects of the density gradients are switched off, with the consequence of no SPM accumulation. These numerical model results motivate future targeted field studies in different Wadden Sea regions with the aim to further support the hypothesis.

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Yoshida, Shuji, Howard D. Johnson, Kenneth Pye, and Richard J. Dixon. "Transgressive changes from tidal estuarine to marine embayment depositional systems: The Lower Cretaceous Woburn Sands of southern England and comparison with Holocene analogs." AAPG Bulletin 88, no. 10 (October 2004): 1433–60. http://dx.doi.org/10.1306/05140403075.

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Dix, George R., and Marianne P. Molgat. "Character of the Middle Ordovician Sauk-Tippecanoe sequence boundary in the Ottawa Embayment (eastern Ontario): possible evidence for platform-interior, Taconic tectonism." Canadian Journal of Earth Sciences 35, no. 6 (June 1, 1998): 603–19. http://dx.doi.org/10.1139/e98-017.

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In eastern Ontario, a Middle Ordovician disconformity that separates predominantly sandstone of the Rockcliffe Formation from underlying dolomite of the Carillon Formation (Beekmantown Group) has, historically, been considered equivalent to the Sauk-Tippecanoe sequence boundary. The character of the formation contact varies considerably, and includes (1) rare, serrated micropinnacles (centimetres in height); (2) smoothed, irregular to undulose erosional bedforms along shallow (<30 cm) incised channels at least ten's of metres in width; (3) a planar boundary with no obvious evidence of erosion; (4) compaction effects across the boundary, as well as within uppermost Carillon and lowermost Rockcliffe strata; and (5) interbedding of Carillon- and Rockcliffe-like lithologies. The latter two observations suggest that, locally, the disconformity represents a relatively minor gap in time. Local, irregular paleotopography is interpreted as some combination of paleokarst, mechanical erosion, and differential sediment loading. The Carillon-to-Rockcliffe transition, from peritidal carbonates to marine or estuarine sandstones, is punctuated by local, anomalous structural and stratigraphic features: ptygmmatically folded fractures, local disconformities, and deposition, then differential erosion of high-energy fluvial-dominated sediments. Differential erosion, fracturing, and paleokarst are local, anomalous attributes of the pre-Carillon paleosurface as well. Combined, these events bracket Carillon deposition, and are interpreted to reflect local platform-interior tectonism coincident with onset of distal Taconic orogenesis. Platform-interior expression of distant, developing changes in plate-boundary dynamics may be linked to incipient basement reactivation along an underlying, shallowly buried Proterozoic fault system, later manifest as the Ottawa-Bonnechere Graben.

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Kwetche, Paul Gustave Fowe, Marie Joseph Ntamak-Nida, Adrien Lamire Djomeni Nitcheu, Jacques Etame, François Mvondo Owono, Cecile Olive Mbesse, Joseph Bertrand Iboum Kissaaka, Gilbert Ngon Ngon, Sylvie Bourquin, and Paul Bilong. "Facies Analysis and Sequence Stratigraphy of Missole Outcrops: N’Kapa Formation of the South-Eastern Edge of Douala Sub-Basin (Cameroon)." Earth Science Research 7, no. 1 (October 21, 2017): 35. http://dx.doi.org/10.5539/esr.v7n1p35.

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Missole facies description and sequence stratigraphy analysis allow a new proposal of depositional environments of the Douala sub-basin eastern part. The sediments of Missole outcrops (N’kapa Formation) correspond to fluvial/tidal channel to shallow shelf deposits with in some place embayment deposits within a warm and semi-arid climate. Integrated sedimentologic, palynologic and mineralogical data document a comprehensive sequence stratigraphy of this part of the Douala sub-basin. Five facies associations occur: (1) facies association I is characterized by Floodplain deposits; (2) facies association II is Fluvial to mouth bar deposits; (3) facies association III characterise Shallow Shelf deposits; (4) facies association IV represents Distal bay or Lacustrine déposits; and (5) Facies association V is made of Fluvial channel deposits. Six depositional sequences were identified. These sequences are composed of four progradational sequences and two retrogradational sequences containing a fluvial channel portion represented by lag deposits at the base of retrogradational sequences. These deposits represent the outset of the relative sea level rise period. In the study area, the N’kapa Formation is composed of non-marine/coastal aggradational deposits representing the early stage of the regressive period. The occurrence of the estuarine/bay deposits with paleosols development is interpreted as evidence of climate change with significant relative base level fluctuation. The study of key minerals associated to sequence stratigraphy as well as palynology demonstrated that sequence architecture has been controlled mostly by climate evolution and outcrops are dated Paleocene – early Eocene.

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Journal articles on the topic 'Estuarine embayment'

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