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Macrophytes as bioindicators of heavy metal pollution in estuarine and coastal environments
2018
Farias, D.R. | Hurd, C.L. | Eriksen, R.S. | Macleod, C.K.
The Derwent estuary, in Tasmania (Australia), is highly contaminated with heavy metals with significant levels in both sediments and benthic fauna. However, little is known about metal content in benthic primary producers. We characterized metal content (Arsenic, Cadmium, Copper, Lead, Selenium and Zinc) in twelve species of macrophyte, including red, green, and brown algae, and seagrasses, from the Derwent. The metals, arsenic, copper, lead, and Zinc were detected in all of the macrophytes assessed, but the levels differed between species. Seagrasses accumulated the highest concentrations of all metals; with Zn levels being particularly high in the seagrass Ruppia megacarpa (from the upper Estuary) and Pb was detected in Zostera muelleri (from the middle estuary). Ulva australis was ubiquitous throughout the middle-lower estuary and accumulated Zn in relatively high concentrations. The findings suggest that analysis of multiple species may be necessary for a comprehensive understanding of estuary-wide metal pollution.
Показать больше [+] Меньше [-]Hexabromocyclododecanes (HBCDs) in fish: Evidence of recent HBCD input into the coastal environment
2018
Sun, Runxia | Luo, Xiaojun | Zheng, Xiaobo | Fanhuolaoren, | Peng, Pingan | Li, Qing X. | Mai, Bixian
Hexabromocyclododecanes (HBCDs) are flame retardants and emerging persistent organic pollutants. In the present study, α-, β-, and γ-HBCDs were measured in several fish species from rivers and an electronic waste (e-waste) recycling site in Pearl River Delta, South China. The concentrations of HBCDs were 12.8 to 640, 5.90 to 115, and 34.3 to 518ng/g lipid weight (lw) in mud carp (Cirrhinus molitorella), tilapia (Tilapia nilotica), and plecostomus (Hypostomus plecostomus), respectively. Plecostomus showed the highest HBCD concentrations among three fish species. The contributions of α-HBCD to total HBCDs were 78% to 97%, 93% to 99%, and 87% to 98% in carp, tilapia, and plecostomus, respectively. Fish samples from a harbor and the e-waste site exhibited the highest HBCD concentrations among all samples. The HBCD concentrations were not significantly correlated with the gross domestic product or population data. e-Waste recycling activities, harbor construction, and shipment might be recent HBCD sources.
Показать больше [+] Меньше [-]Sustainable recycling of mooring ropes from decommissioned offshore platforms
2018
Sudaia, David Pascoal | Bastos, Milton Briguet | Fernandes, Elieti Biques | Nascimento, Christine Rabello | Pacheco, Elen B.A.V. | da Silva, Ana Lúcia N.
Decommissioning offshore Floating Production, Storage and Offloading (FPSO) platforms requires extensive technical knowledge, since it generates different post-consumer materials, including mooring lines. These ropes are made from polyester high tenacity yarn, based on polyethylene terephthalate (PET), and their high added value means they should not be discarded as scrap. This paper aims to present a review and technical opportunities, from an economic standpoint, of recycling the mooring lines recovered from decommissioned FPSOs. Studies conducted over the last two years have researched and developed different potential applications for the fibers. These studies include collaborative project initiatives involving technical and management professionals, universities and private enterprises, with a view to achieving a more sustainable destination for these fibers.
Показать больше [+] Меньше [-]Assessing the ecological status of Italian lagoons using a biomass-based index
2018
Mistri, Michele | Borja, Angel | Aleffi, Ida Floriana | Lardicci, Claudio | Tagliapietra, Davide | Munari, Cristina
We compared the performance of abundance- and biomass-based M-AMBI in the 13 major Italian lagoons, using a benthic dataset constituted by 208 sampling sites. The relative importance of ecological groups changed when using abundance or biomass, sometimes leading to an improved ecological status classification. Being biomass more ecologically relevant than abundance, the adoption of a biomass-based index may better describe the ecological status of lagoons, where the community is naturally disturbed and dominated by tolerant and opportunist species.
Показать больше [+] Меньше [-]Occurrence and distribution of perfluoroalkyl substances (PFASs) in sediments of the Dalian Bay, China
2018
Ding, Guanghui | Xue, Huanhuan | Zhang, Jing | Cui, Fuxu | He, Xin
In the present study, the spatial distributions and vertical variations of PFASs in the sediments of the Dalian Bay were investigated. The total concentrations of PFASs (∑PFASs) in surface sediments of Dalian Bay ranged from 1.49 to 2.66ngg⁻¹ dw. The predominant PFASs in surface sediments were PFOA, PFBS and PFBA with the concentration ranges of 0.50 to 0.95, 0.21 to 0.94, and 0.035 to 0.32ngg⁻¹ dw, respectively. For the two sediment cores, ∑PFASs ranged from 1.20 to 2.00 and from 1.37 to 2.06ngg⁻¹ dw, respectively. There was a maximum ∑PFASs concentration value near the surface. In general, ∑PFASs gradually decreased with increasing sampling depth after reaching the maximum. PFOA, PFBS and PFBA were also the predominant PFASs in the two sediment cores. It is recommended that the monitoring and risk assessment of short-chain PFAS should be taken into consideration, and further researches are needed to understand the transportation and fate of these chemicals in the aquatic environment.
Показать больше [+] Меньше [-]Mercury and methylmercury transport and fate in the water column of Tagus estuary (Portugal)
2018
Cesário, Rute | Mota, Ana Maria | Caetano, Miguel | Nogueira, Marta | Canário, João
Six campaigns were performed in North Channel (CNOR), Barcas Channel (BC) and lower zones (EZ) of Tagus estuary to better understand methylmercury (MMHg) and mercury (Hg) transport and fate.Highest concentrations of particulate and dissolved MMHg were observed in CNOR in bottom waters and in the warmest months. The MMHg distribution coefficients between particulate and dissolved fractions were mainly influenced by particulate matter and dissolved organic carbon. The values were slightly higher in summer than in winter and in CNOR. Overall, results established that the tidal effect is a main driver on the transport and fate of Hg and MMHg from CNOR to outer areas, evidenced by the exportation of the Hg species from CNOR to the upstream station in high tide and to the downstream one in low tide. Therefore, CNOR may be considered a source of Hg and MMHg to the outer estuary.
Показать больше [+] Меньше [-]Effects of dissolved oxygen and nutrient loading on phosphorus fluxes at the sediment–water interface in the Hai River Estuary, China
2018
Kang, Mengxin | Peng, Sen | Tian, Yimei | Zhang, Haiya
The effects of dissolved oxygen and nutrient loading on the concentrations and species of phosphorus at the sediment–water interface were evaluated under laboratory conditions. The results showed that the redox potential was significantly correlated with the total phosphorus, total dissolved phosphorus, total nitrogen, ammonium and nitrate nitrogen levels in an aerobic setting, but no significant correlations were observed under anaerobic conditions. The dynamic equilibrium between the overlying water and sediment tended to balance out over time, and the concentration gradient reduced, when the nutrient loading was changed. The greatest variation was observed in the level of iron/aluminum-bound phosphorus, while the calcium-bound phosphorus and organic phosphorus contents showed relatively minor changes. This study not only illustrates the phosphorus transfer mechanism between sediment and water, but can also contribute to the management and protection of Bohai Bay.
Показать больше [+] Меньше [-]Leave no traces – Beached marine litter shelters both invasive and native species
2018
García Vázquez, Eva | Cani, Alessandra | Diem, Anna | Ferreira, Catarina | Geldhof, Ruben | Márquez, Lidia | Molloy, Eoin | Perché, Sarah
Marine litter has been considered a potential transport vector of non-indigenous species. In this study developed in Tjärnö (Sweden), at the entry of the Baltic Sea, the communities inhabiting coastal litter and natural substrates (N = 5448 macroorganisms) were monitored from eight sites of different ecological conditions. The results showed that litter can support high densities of marine organisms and represent a new habitat in the studied coast. The taxonomic profile of the communities supported by marine litter and hard natural substrate were significantly different. Moreover, opposite to the expectations of reduced diversity in artificial structures, more diverse communities were found on litter. Non-indigenous species were attached mainly to non-plastic artificial materials. From these results it can be concluded that marine litter can significantly alter the biotic composition of coastal ecosystem, representing a shelter for invasive species and diverse natives.
Показать больше [+] Меньше [-]Microbial communities of polluted sub-surface marine sediments
2018
Catania, Valentina | Cappello, Simone | Di Giorgi, Vincenzo | Santisi, Santina | Di Maria, Roberta | Mazzola, Antonio | Vizzini, Salvatrice | Quatrini, Paola
Microbial communities of coastal marine sediment play a key role in degradation of petroleum contaminants. Here the bacterial and archaeal communities of sub-surface sediments (5–10 cm) of the chronically polluted Priolo Bay (eastern coast of Sicily, Italy), contaminated mainly by n-alkanes and biodegraded/weathered oils, were characterized by cultural and molecular approaches. 16S-PCR-DGGE analysis at six stations, revealed that bacterial communities are highly divergent and display lower phylogenetic diversity than the surface sediment; sub-surface communities respond to oil supplementation in microcosms with a significant reduction in biodiversity and a shift in composition; they retain high biodegradation capacities and host hydrocarbon (HC) degraders that were isolated and identified. HC-degrading Alfa, Gamma and Epsilon proteobacteria together with Clostridia and Archaea are a common feature of sub-surface communities. These assemblages show similarities with that of subsurface petroleum reservoirs also characterized by the presence of biodegraded and weathered oils where anaerobic or microaerophilic syntrophic HC metabolism has been proposed.
Показать больше [+] Меньше [-]Securing a port's future through Circular Economy: Experiences from the Port of Gävle in contributing to sustainability
2018
Carpenter, Angela | Lozano, Rodrigo | Sammalisto, Kaisu | Astner, Linda
Ports are an important player in the world, due to their role in global production and distributions systems. They are major intermodal transport hubs, linking the sea to the land. For all ports, a key requirement for commercial and economic viability is to retain ships using them and to remain accessible to those ships. Ports need to find approaches to help them remain open. They must ensure their continued economic viability. At the same time, they face increasing pressure to become more environmentally and socially conscious. This paper examines the approach taken by the Port of Gävle, Sweden, which used contaminated dredged materials to create new land using principles of Circular Economy. The paper demonstrates that using Circular Economy principles can be a viable way of securing a port's future and contributing to its sustainability, and that of the city/region where it operates.
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