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Selection of parameters for seagrass management: Towards the development of integrated indicators for French Antilles
2021
Kerninon, Fanny | Payri, Claude E. | Le Loch, Francois | Alcoverro, Teresa | Maréchal, Jean-philippe | Chalifour, Julien | Gréaux, Sebastien | Mège, Simone | Athanase, Julien | Cordonnier, Sébastien | Rouget, Marie-laure | Lorre, Elise | Uboldi, Thomas | Monnier, Olivier | Hellio, Claire
Seagrass beds are increasingly impacted by human activities in coastal areas, particularly in tropical regions. The objective of this research program was to study seagrass beds characteristics under various environmental conditions in the French Antilles (FA, Caribbean Sea). A total of 61 parameters, from plant physiology to seagrass ecosystem, were tested along a gradient of anthropogenic conditions, distributed across 11 sites and 3 islands of the FA. A selection of 7 parameters was identified as relevant for the monitoring of seagrass meadows in the framework of public policies. They combined “early warning indicators” (e.g. nutrients and some trace metals) and long-term responding parameters (e.g. shoot density) adapted to management time scales. The ecological status of seagrass meadows was evaluated using a PCA. This work is a first step towards monitoring and management of seagrass meadows in the FA.
Afficher plus [+] Moins [-]Selection of parameters for seagrass management: Towards the development of integrated indicators for French Antilles
2021
Kerninon, Fanny | Payri, Claude E. | Le Loc'h, François | Alcoverro, Teresa | Maréchal, Jean-Philippe | Chalifour, Julien | Gréaux, Sébastien | Mège, Simone | Athanase, Julien | Cordonnier, Sébastien | Rouget, Marie-Laure | Lorre, Elise | Uboldi, Thomas | Monnier, Olivier | Hellio, Claire
Seagrass beds are increasingly impacted by human activities in coastal areas, particularly in tropical regions. The objective of this research program was to study seagrass beds characteristics under various environmental conditions in the French Antilles (FA, Caribbean Sea). A total of 61 parameters, from plant physiology to seagrass ecosystem, were tested along a gradient of anthropogenic conditions, distributed across 11 sites and 3 islands of the FA. A selection of 7 parameters was identified as relevant for the monitoring of seagrass meadows in the framework of public policies. They combined “early warning indicators” (e.g. nutrients and some trace metals) and long-term responding parameters (e.g. shoot density) adapted to management time scales. The ecological status of seagrass meadows was evaluated using a PCA. This work is a first step towards monitoring and management of seagrass meadows in the FA.
Afficher plus [+] Moins [-]Identification of hazardous nanoparticles present in the Caribbean Sea for the allocation of future preservation projects
2021
Silva, Luis F.O. | Lozano, Liliana P. | Oliveira, Marcos L.S. | da Boit, Kátia | Gonçalves, Janaína O. | Neckel, Alcindo
The deposition of remaining nanoparticles in the Caribbean Sea generates the formation of potentially dangerous elements, which influence at the imbalance of ecosystems. The detection of nanoparticles is not simple and the use of conventional methods is difficult application, which is why we highlight the immediacy and importance of this research for the areas of marine biology, urbanism, engineering and geosciences, applied in the Caribbean Sea. The general objective of this study is to evaluate the use of advanced methods for the determination of toxic nanoparticles, which can directly affect the development of marine organisms in the aquatic ecosystem in waters of the Caribbean Sea, favoring the construction of future international public policies with the elaboration of projects capable of mitigating these levels of contamination. The morphology and structure of nanoparticles were analyzed by emission scanning electron microscope with a high-resolution electron microscope. The nanoparticles smaller than 97 nm were identified in different proportions. The morphological analyses indicated nanoparticles' presence in the form of nanotubes, nanospheres, and nanofibers, which were shown in an agglomerated form. The presence of potentially hazardous elements, such as As, Cd, Pb, Mg, Ni and V were verified. In addition, the presence of asbestos in the form of minerals was confirmed, and that of titanium dioxide was found in large quantities. The results provide new data and emphasize the possible consequences to the in the Caribbean Sea, with the identification of dangerous elements (As, Cb, Pb, Hg, Ni and V), harmful to the marine ecosystem. Therefore, there is a need for strict control to reduce contamination of the Caribbean Sea and avoid risks to the ecosystem and public health, through suggestions of international public policies, through constant monitoring and the application of environmental recovery projects in this marine estuary.
Afficher plus [+] Moins [-]Sedimentary record of the impact of management actions on pollution of Cartagena bay, Colombia
2021
Espinosa-Díaz, Luisa F. | Sánchez-Cabeza, Joan-Albert | Sericano, Jose Luis | Parra, Juan Pablo | Ibarra-Gutierrez, Karen P. | Garay-Tinoco, Jesus Antonio | Betancourt-Portela, Julian Mauricio | Alonso-Hernández, Carlos | Ruiz-Fernández, Ana Carolina | Quejido-Cabezas, Alberto | Díaz-Asencio, Misael
The reconstruction of pollution in aquatic ecosystems is a useful tool to evaluate the effectiveness of management actions. Cartagena Bay (Colombia, Caribbean Sea) is one of the most impacted coastal zones in Colombia by a wide variety of human activities. A sediment core was dated using ²¹⁰Pb and used to reconstruct the historical input of heavy metals, polycyclic aromatic hydrocarbons (PAHs), and organochlorinated pesticides to the bay. The highest pollutant concentrations were observed in the deeper core layers. The maximum mercury concentration (18.76 μg g⁻¹) was observed at 61 cm depth, corresponding to 1967, when a chlor-alkali plant was operating. Since all pollutant concentrations have decreased due to better industrial management policies, their presence is a potential contamination risk through sediment remobilization and pollutant resuspension.
Afficher plus [+] Moins [-]Spatial distribution of pesticides, organochlorine compounds, PBDEs, and metals in surface marine sediments from Cartagena Bay, Colombia
2021
Duarte-Restrepo, Edisson | Noguera-Oviedo, Katia | Butryn, Deena | Wallace, Joshua S. | Aga, Diana S. | Jaramillo-Colorado, Beatriz E.
Cartagena Bay is an estuarine system located in the Caribbean Sea (Colombia, South America), that receives fresh water from Canal del Dique, which is connected to the Magdalena River, the most important river of Colombia, with some of the most prominent Colombian cities located in its watershed, which has a high sediment yield. An analysis of persistent organic pollutants and heavy metals was carried out on marine sediments from Cartagena Bay. Cartagena Bay sediments deployed the occurrence of total levels of pesticides (thiocarbamates, bromacil, triazines, organochlorines, and organophosphorus), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs), in sediments ranging from 0.83–33.67 ng/g dry-weight, 0.05–0.34 ng/g dry-weight, and 0.06–19.58 ng/g dry-weight, respectively. Their concentrations were lower than those reported in NOAA Screening Quick Reference Tables. DDTs and PCBs are banned organochlorine compounds, since, even at low levels, their presence in sediments represents a threat to aquatic organisms and, therefore, to human health through the trophic chain. Sediments showed high concentrations of strontium (50–959.6 mg/kg). All metals evaluated in the marine sediments were found in the S6 sampling point; this was near tannery and hydrocarbon industries (Pb 37.1 mg/kg, Cr 137.2 mg/kg, Cd 1.7 mg/kg, Cu 64.4 mg/kg, As 13.1 mg/kg, Sr 318.9 mg/kg); these results exceeded the accepted values of threshold effect levels (TEL) used as an indicator of their potential risk on marine life.
Afficher plus [+] Moins [-]Retrospective assessment of pregnancy exposure to particulate matter from desert dust on a Caribbean island: could satellite-based aerosol optical thickness be used as an alternative to ground PM10 concentration?
2021
Tuffier, Stéphane | Upegui, Erika | Raghoumandan, Christina | Viel, Jean-François
Desert dust transported from the Saharan-Sahel region to the Caribbean Sea is responsible for peak exposures of particulate matter (PM). This study explored the potential added value of satellite aerosol optical thickness (AOT) measurements, compared to the PM concentration at ground level, to retrospectively assess exposure during pregnancy. MAIAC MODIS AOT retrievals in blue band (AOT₄₇₀) were extracted for the French Guadeloupe archipelago. AOT₄₇₀ values and PM₁₀ concentrations were averaged over pregnancy for 906 women (2005–2008). Regression modeling was used to examine the AOT₄₇₀-PM₁₀ relationship during pregnancy and test the association between dust exposure estimates and preterm birth. Moderate agreement was shown between mean AOT₄₇₀ retrievals and PM₁₀ ground-based measurements during pregnancy (R² = 0.289). The magnitude of the association between desert dust exposure and preterm birth tended to be lower using the satellite method compared to the monitor method. The latter remains an acceptable trade-off between epidemiological relevance and exposure misclassification, in areas with few monitoring stations and complex topographical/meteorological conditions, such as tropical islands.
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