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Non-native plant species in the Atlantico Department Coastal Dune Systems, Caribbean of Colombia: A new management challenge
2019
Gracia C., Adriana | Rangel-Buitrago, Nelson | Castro-Barros, Julian Dario
Although coastal dunes exhibit typical vegetation which involves species adapted to extreme environmental conditions, the mobilization and colonization by non-native species represents a challenge in its conservation and management. In this work, eight dune systems located along the Atlantico Department, Caribbean coast of Colombia were surveyed, finding within them the presence of two plant species recognized as invasive: Calotropis procera and Cryptostegia madagascariensis. The impacts of these two invasive plant species can be significant at all ecological levels in the dune systems. The above demands the implementation of urgent management actions. Eradication seems the optimal control alternative, however preventing invasive plant species from infesting new areas is more cost-effective and efficient than trying to restore the system after it is infested. Data presented in this paper is the first step in the future development of an early detection program in the study area.
显示更多 [+] 显示较少 [-]Vulnerability to bioinvasions: Current status, risk assessment and management of ballast water through a regional approach – the Adriatic Sea
2019
David, Matej | Magaletti, Erika | Kraus, Romina | Marini, Mauro
The United Nations recognised the transfer of invasive species across natural barriers as one of the greatest pressures to the world's oceans and seas. The BWM Convention sets the global standards on ballast water management (BWM) requirements, while recognising that regional and local specifics have to be considered for its effective implementation. In the Adriatic Sea cross-border activities were conducted to provide for essential information/data and tools to support a regionally coordinated implementation of the BWM Convention. This special issue contains 18 publications that include results and recommendations from studying the ballast water and management issues through sampling of ballast water on vessels, risk assessment for exemptions and BWM, biological and chemical port baseline surveys and monitoring conducted in ports along the Adriatic Sea coast, oceanographic conditions, ballast water sediment issues and their management in ports, and the implementation options of the BWM Convention through the Adriatic States' environmental law and institutions cooperation. Essential data and tools to support a regional approach in the implementation of the BWM Convention were provided, and are therefore available to the administrations of the Adriatic countries to enable protection of the Adriatic Sea environment, human health property and resources from negative impacts of ballast water being discharged in the area. Data, approaches and tools provided here may be helpful in any other region to support an effective BWM Convention implementation.
显示更多 [+] 显示较少 [-]Live fast, die young: Behavioural and physiological impacts of light pollution on a marine fish during larval recruitment
2019
O'Connor, J.J. | Fobert, E.K. | Besson, M. | Jacob, H. | Lecchini, D.
Artificial light at night (ALAN) is a recently acknowledged form of anthropogenic pollution of growing concern to the biology and ecology of exposed organisms. Though ALAN can have detrimental effects on physiology and behaviour, we have little understanding of how marine organisms in coastal areas may be impacted. Here, we investigated the effects of ALAN exposure on coral reef fish larvae during the critical recruitment stage, encompassing settlement, metamorphosis, and post-settlement survival. We found that larvae avoided illuminated settlement habitats, however those living under ALAN conditions for 10 days post-settlement experienced changes in swimming behaviour and higher susceptibility to nocturnal predation. Although ALAN-exposed fish grew faster and heavier than control fish, they also experienced significantly higher mortality rates by the end of the experimental period. This is the first study on the ecological impacts of ALAN during the early life history of marine fish.
显示更多 [+] 显示较少 [-]Assessment of input of organic micropollutants and microplastics into the Baltic Sea by urban waters
2019
Bollmann, Ulla E. | Simon, Marta | Vollertsen, Jes | Bester, Kai
We assess how different micropollutants and microplastics, connected to wastewater are introduced into the Baltic Sea. The relevance of untreated wastewater, treated wastewater, treated and untreated rain runoff, as well as combined sewer overflow (CSO), is assessed in respect to mass balance, as well as relative inflows of micropollutants and -plastics into the Baltic Sea. To achieve this, modelling based on data on exemplary sewer systems and measured micropollutant concentrations in the single sources were used. Most compounds reach the receiving Baltic Sea via treated wastewater. A few exceptions are compounds that are removed to a very high extent in wastewater treatment plants. For these compounds, the emissions with stormwater (e.g., terbutryn) or untreated wastewater (e.g., triclosan) are dominating. Additionally, compounds that are discharged with the water that is running off urban surfaces are introduced into marine areas via rain runoff. These data are used to forecast a total mass load and concentrations that can be expected in the Baltic Sea. Massloads are expected to be between 0.1 and 5.9 t/a for triclosan and TCPP (tris (2-chloropropyl) phosphate) and 0.2 t/a for microplastic particles. The expected concentrations in open Baltic Sea waters range from 0.01 to 26 ng/L.
显示更多 [+] 显示较少 [-]Spatial variation of trace element concentration and contamination assessment in the coral reef sediments of Lakshadweep Archipelago, Indian Ocean
2019
Joy, Anu | P P, Anoop | R, Rajesh | Mathew, Jose | Mathew, Angel | Gopinath, Anu
Surface sediments were collected from the shore and lagoons of Kavaratti, Kadmat and Agatti islands of Lakshadweep Archipelago and analysed for trace element concentration. The sediment contamination was assessed on the basis of geochemical, biological hazard and ecological risk indices. Except Cd and Pb, all the other trace elements selected for the study were below the contamination level. Compared to Kadmat, Kavaratti and Agatti were more polluted and the pollution was pronounced in lagoons than shore. Population pressure, untreated sewage, diesel based power generation, shipping and tourism activities contribute to sediment contamination. Statistical analysis revealed the association of trace elements with sedimentary characteristics due to anthropogenic sources.
显示更多 [+] 显示较少 [-]The distribution of sediment bacterial community in mangroves across China was governed by geographic location and eutrophication
2019
Tong, Tianli | Li, Ruili | Wu, Sijie | Xie, Shuguang
Bacterial community is an important component of mangrove ecosystem and can participate in the cycling of elements and promote plant growth. However, the biogeographic distribution pattern of mangrove bacterial community and the associated factors remain poorly known. The present study explored the biogeographic distribution of sediment bacterial community in six mangroves across China. At each mangrove, sediments were collected from both Avicennia marina-planted zones and intertidal mudflats. The community abundance, richness, diversity and structure of sediment bacteria differed greatly among mangrove wetlands. Plantation showed a positive influence on sediment bacterial abundance, richness and diversity. Proteobacteria was the largest bacterial phylum in sediments. The biogeographic distribution of bacterial community in mangroves across China was driven by the variables associated with the wetland trophic status as well as other physicochemical factors (e.g., salinity).
显示更多 [+] 显示较少 [-]Trace element concentrations, ecological and health risk assessment in sediment and marine fish Otolithes ruber in Oman Sea, Iran
2019
Sadeghi, Parvin | Loghmani, Mehran | Afsa, Elahe
This study aimed to investigate the concentration of Cd, Ni, Cr, Pb and As in the tissues of Otolithes ruber and surface sediments in the Oman Sea. Trace element concentrations were analyzed by flame atomic absorption spectrophotometer (FAAS) for ecological and health risk assessment. The results showed a significant difference in trace element concentrations of the liver, muscle and sediments between different stations (p < 0.05). Potential ecological risk index (PER) indicated very high risk for Cd at all stations. Estimated daily intake (EDI) for consumption of Otolithes ruber for Cr, Pb and As was lower than tolerable daily intake (TDI). The mean target hazard quotient (THQ) of Cd and Ni were higher than 1 at all stations. Target cancer risk (TR) for Ni and As were higher than the acceptable value range at all stations. Accordingly, the risk of cancer due to the long-term consumption of this fish can be concerned.
显示更多 [+] 显示较少 [-]Oil behavior in sea ice: Changes in chemical composition and resultant effect on sea ice dielectrics
2019
Desmond, Durell S. | Saltymakova, Diana | Neusitzer, Thomas D. | Firoozy, Nariman | Isleifson, Dustin | Barber, David G. | Stern, Gary A.
There has been increasing urgency to develop methods for detecting oil in sea ice owing to the effects of climate change in the Arctic. A multidisciplinary study of crude oil behavior in a sea ice environment was conducted at the University of Manitoba during the winter of 2016. In the experiment, medium-light crude oil was injected underneath young sea ice in a mesocosm. The physical and thermodynamic properties of the oil-infiltrated sea ice were monitored over a three-week time span, with concomitant analysis of the oil composition using analytical instrumentation. A resonant perturbation technique was used to measure the oil dielectric properties, and the contaminated sea ice dielectric properties were modeled using a mixture model approach. Results showed that the interactions between the oil and sea ice altered their physical and thermodynamic properties. These changes led to an overall decrease in sea ice dielectrics, potentially detectable by remote sensing systems.
显示更多 [+] 显示较少 [-]VanA-type vancomycin-resistant Enterococcus faecium ST1336 isolated from mussels in an anthropogenically impacted ecosystem
2019
Sacramento, Andrey G. | Fernandes, Miriam R. | Sellera, Fábio P. | Dolabella, Silvio S. | Zanella, Rosemeire C. | Cerdeira, Louise | Lincopan, Nilton
We report the occurrence and genomic features of multidrug-resistant vancomycin-resistant Enterococcus faecium vanA belonging to a novel sequence type (designated ST1336), carrying a Tn1546-like element, in marine brown mussels (Perna perna) from anthropogenically affected coastal waters of the Atlantic coast of Brazil, highlighting a potential source of dissemination for related ecosystems, with additional consequences for seafood safety and quality.
显示更多 [+] 显示较少 [-]Assessment of metal contamination in Arabian/Persian Gulf fish: A review
2019
Cunningham, Patricia A. | Sullivan, Elizabeth E. | Everett, Kibri H. | Kovach, Samuel S. | Rajan, Anbiah | Barber, Mary C.
Metal contamination in fish is a concern worldwide, including in the Arabian/Persian Gulf region. This review summarizes the findings from 55 papers about metal concentrations in Gulf fish. Metal concentrations in muscle tissue were screened against the most recent maximum allowable levels (MALs) for fish in international commerce. We identified metals, fish species, and locations where concentrations exceeded the MALs. For some metals, recent MALs have been set to lower concentrations as more toxicological data have become available. Mean fish tissue concentrations exceeded the MAL in 13% (arsenic), 76% (cadmium), 56% (lead), and 10% (mercury) of species means. We identified 13 fish species with the potential to serve as bioindicators of metal contamination for use in four Gulf habitats: pelagic, benthopelagic, demersal, and coral reefs. Recommendations are provided for a regional approach to improve consistency of sampling, data analysis and reporting of metal concentrations in Gulf fish.
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