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Cu, Pb and Fe release from sulfide-containing tailings in seawater: Results from laboratory simulation of submarine tailings disposal Texto completo
2018
Embile, Rodrigo F. | Walder, Ingar F. | Schuh, Christopher | Donatelli, Jenna Lee
Metal release from the deposition of sulfide-containing tailings in seawater was investigated using a batch reaction experiment inside a temperature and dissolved oxygen-controlled chamber. Two hundred grams of tailings from a porphyry Cu-Au and a sediment-hosted Cu deposit were submerged in 1.8 L synthetic seawater. The sulfides present in the porphyry Cu-Au tailings are pyrite (FeS2), chalcopyrite (CuFeS2) and bornite (Cu5FeS4) while in the sediment-hosted Cu tailings are bornite, chalcocite (Cu2S) and covellite (CuS). Galena occurs as a minor sulfide in both tailings. Pore water and overlying seawater samples were collected and analyzed for pH, redox potential and trace metals (Cu, Pb and Fe) concentration. Results show that there is very low Cu (10–40 μg/L), Pb (1–10 μg/L) and Fe (5–50 μg/L) released into solution throughout the course of 87 days. Long-term trace metal release from tailings in seawater is therefore theorized to be low and is a slow process.
Mostrar más [+] Menos [-]Distribution, sources, and ecological risk assessment of quinotone antibiotics in the surface sediments from Jiaozhou Bay wetland, China Texto completo
2018
Liu, Ke | Yin, Xiaofei | Zhang, Daolai | Yan, Dongyun | Cui, Lijuan | Zhu, Zhigang | Wen, Li
The distribution, sources, and risk assessment of eight quinotone antibiotics (QNs) in the surface sediments from the wetland in Jiaozhou Bay were investigated. The results showed that QNs were detected in all samples, and the total concentrations of QNs in the sediments ranged from 0.276 to 5.229ng/g. The highest concentration occurred at the entrance to the Yang River wetland. Principal component analysis suggested that the QNs mainly originated from sewage discharges from hospitals, human and aquaculture industries. Risk assessment, based on risk quotients, indicated the current ofloxacin level might be a medium risk level, while other QNs were all low risk. Nevertheless, there should still be concerns due to high consumption of QNs by human beings, animals, and aquatic organisms in the wetland. This investigation provides baseline data that the government can use as a reference guide to control QNs residues in Jiaozhou Bay wetland.
Mostrar más [+] Menos [-]Screening of human and veterinary pharmaceuticals in estuarine waters: A baseline assessment for the Tejo estuary Texto completo
2018
Reis-Santos, Patrick | Pais, Miguel | Duarte, Bernardo | Caçador, Isabel | Freitas, Andreia | Vila Pouca, Ana S. | Barbosa, Jorge | Leston, Sara | Rosa, João | Ramos, Fernando | Cabral, Henrique N. | Gillanders, Bronwyn M. | Fonseca, Vanessa F.
Screening of human and veterinary pharmaceuticals in estuarine waters: A baseline assessment for the Tejo estuary Texto completo
2018
Reis-Santos, Patrick | Pais, Miguel | Duarte, Bernardo | Caçador, Isabel | Freitas, Andreia | Vila Pouca, Ana S. | Barbosa, Jorge | Leston, Sara | Rosa, João | Ramos, Fernando | Cabral, Henrique N. | Gillanders, Bronwyn M. | Fonseca, Vanessa F.
We investigated the presence of 66 human and veterinary pharmaceuticals from seven therapeutic groups in surface waters of the Tejo estuary. Collection sites covered the entire estuary and included areas near main river inflows and wastewater treatment outfalls, traversing urban, agriculture, aquaculture, and nature reserve areas. Detection of pharmaceuticals was performed via UHPLC-TOF-MS. Pharmaceuticals were found in all sites (32 different compounds in total). Antibiotics, β-blockers, antihypertensives and anti-inflammatories were the most frequently detected (>90%), with variation in concentrations reflecting the multifaceted nature of estuarine surroundings (accumulated site contamination between 15 and 351 ng L−1). Higher concentrations of antidepressant Sertraline (304 ng L−1), non-steroidal anti-inflammatory Diclofenac (51.8 ng L−1), lipid regulator Gemfibrozil (77.0 ng L−1), antihypertensive Ibersartan (161.9 ng L−1) or antibiotic Doxycycline (128.0 ng L−1), among others, though localized may potentially impact key estuarine functions or services. Ultimately, results provide a baseline for regulatory information and future biota evaluations.
Mostrar más [+] Menos [-]Screening of human and veterinary pharmaceuticals in estuarine waters: A baseline assessment for the Tejo estuary Texto completo
2018
Reis Santos, Patrick | Pais, Miguel Pessanha | Duarte, Bernardo | Caçador, Isabel | Freitas, Andreia | Vila Pouca, Ana S. | Barbosa, Jorge | Leston, Sara | Rosa, João | Ramos, Fernando | Cabral, Henrique | Gillanders, Bronwyn M. | Fonseca, Vanessa
We investigated the presence of 66 human and veterinary pharmaceuticals from seven therapeutic groups in surface waters of the Tejo estuary. Collection sites covered the entire estuary and included areas near main river inflows and wastewater treatment outfalls, traversing urban, agriculture, aquaculture, and nature reserve areas. Detection of pharmaceuticals was performed via UHPLC-TOF-MS. Pharmaceuticals were found in all sites (32 different compounds in total). Antibiotics, β-blockers, antihypertensives and anti-inflammatories were the most frequently detected (>90%), with variation in concentrations reflecting the multifaceted nature of estuarine surroundings (accumulated site contamination between 15 and 351 ng L-1). Higher concentrations of antidepressant Sertraline (304 ng L-1), non-steroidal anti-inflammatory Diclofenac (51.8 ng L-1), lipid regulator Gemfibrozil (77.0 ng L-1), antihypertensive Ibersartan (161.9 ng L-1) or antibiotic Doxycycline (128.0 ng L-1), among others, though localized may potentially impact key estuarine functions or services. Ultimately, results provide a baseline for regulatory information and future biota evaluations. | info:eu-repo/semantics/publishedVersion
Mostrar más [+] Menos [-]Mapping widespread and increasing underwater noise pollution from acoustic deterrent devices Texto completo
2018
Findlay, C.R. | Ripple, H.D. | Coomber, F. | Froud, K. | Harries, O. | van Geel, N.C.F. | Calderan, S.V. | Benjamins, S. | Risch, D. | Wilson, B.
Acoustic deterrent devices (ADDs) are used in attempts to mitigate pinniped depredation on aquaculture sites through the emission of loud and pervasive noise. This study quantified spatio-temporal changes in underwater ADD noise detections along western Scotland over 11 years. Acoustic point data (‘listening events’) collected during cetacean line-transect surveys were used to map ADD presence between 2006 and 2016. A total of 19,601 listening events occurred along the Scottish west coast, and ADD presence was recorded during 1371 listening events. Results indicated a steady increase in ADD detections from 2006 (0.05%) to 2016 (6.8%), with the highest number of detections in 2013 (12.6%), as well as substantial geographic expansion. This study demonstrates that ADDs are a significant and chronic source of underwater noise on the Scottish west coast with potential adverse impacts on target (pinniped) and non-target (e.g. cetaceans) species, which requires further study and improved monitoring and regulatory strategies.
Mostrar más [+] Menos [-]UV fluences required for compliance with ballast water discharge standards using two approved methods for algal viability assessment Texto completo
2018
Lundgreen, Kim | Holbech, Henrik | Pedersen, Knud Ladegaard | Petersen, Gitte Ingelise | Andreasen, Rune Røjgaard | George, Christaline | Drillet, Guillaume | Andersen, Martin
This study investigates the extra UV fluence needed to meet the International Maritime Organisation's ballast water discharge standards for the 10–50 μm size-class using the approved vital stain (VS) method compared to the Most Probable Number (MPN) method for organism viability assessment. Low- and medium pressure UV collimated beam treatments were applied to natural algae collected in temperate and tropical water environments and analysed using both methods. About 10 times higher UV fluence was required to meet discharge standards when using VS compared to MPN. Implementing a dark-hold period after UV treatments decreased algal viability. Length of dark-hold period to meet discharge standards decreased with increasing UV fluence. No significant differences between temperate and tropical samples were observed. The results showed that UV treated algae assessed using the VS method could meet discharge standards by increasing fluence and/or introducing a dark-hold period.
Mostrar más [+] Menos [-]Long term development of Bathing Water Quality at the German Baltic coast: spatial patterns, problems and model simulations Texto completo
2018
Buer, Anna-Lucia | Gyraite, Greta | Wegener, Patrick | Lange, Xaver | Katarzyte, Marija | Hauk, Gerhard | Schernewski, Gerald
Bathing water quality plays a key role for public health, is highly important for recreational tourism and therefore monitored in the EU-Directive 2006/7/EC. To identify pollution hot spots, sources and impacts of the directive-change in 2006, including a change of indicator organisms, we evaluated monitoring data of the past 15 years, collected own data, determined survival rates of indicator organisms and applied hydrodynamic modelling in a micro-tidal-system.Due to higher survival rates under turbid conditions and restricted water exchange, shallow, eutrophic bays and lagoons are hot spots of microbial pollution. Rain events cause high microbial emission and distribution. Based on different decay rates, the ratio of E. coli to Enterococci can hint towards a pollution source. Including rain predictions, currents and winds, hydrodynamic models can then assess the daily risk of microbial pollution at each bathing site. They are an important tool to modify beach management and event-based monitoring.
Mostrar más [+] Menos [-]Tropical sea cucumber fisheries: Changes during the last decade Texto completo
2018
Conand, C.
Tropical sea cucumber fisheries are generally traditional, small-scale, multispecies and poorly managed. Many recent studies have improved our knowledge on the biology and ecology of the commercially important species; the main results are analysed and the remaining gaps discussed. The fisheries and the patterns of trade changes during the last decade are presented from the data available and confirm overexploitation in the traditional Indian Ocean and West Pacific countries and territories. Several Latino-American countries now have active fisheries. Despite the management and conservation issues which have recently received more attention at international, regional and national levels, more measures are still needed at all these levels, to ensure sustainable exploitations of these resources.
Mostrar más [+] Menos [-]Mapping coastal marine debris using aerial imagery and spatial analysis Texto completo
2018
Moy, Kirsten | Neilson, Brian | Chung, Anne | Meadows, Amber | Castrence, Miguel | Ambagis, Stephen | Davidson, Kristine
This study is the first to systematically quantify, categorize, and map marine macro-debris across the main Hawaiian Islands (MHI), including remote areas (e.g., Niihau, Kahoolawe, and northern Molokai). Aerial surveys were conducted over each island to collect high resolution photos, which were processed into orthorectified imagery and visually analyzed in GIS. The technique provided precise measurements of the quantity, location, type, and size of macro-debris (>0.05m²), identifying 20,658 total debris items. Northeastern (windward) shorelines had the highest density of debris. Plastics, including nets, lines, buoys, floats, and foam, comprised 83% of the total count. In addition, the study located six vessels from the 2011 Tōhoku tsunami. These results created a baseline of the location, distribution, and composition of marine macro-debris across the MHI. Resource managers and communities may target high priority areas, particularly along remote coastlines where macro-debris counts were largely undocumented.
Mostrar más [+] Menos [-]Biogeographic vulnerability to ocean acidification and warming in a marine bivalve Texto completo
2018
Van Colen, Carl | Jansson, Anna | Saunier, Alice | Lacoue-Labathe, Thomas | Vincx, Magda
Biogeographic vulnerability to ocean acidification and warming in a marine bivalve Texto completo
2018
Van Colen, Carl | Jansson, Anna | Saunier, Alice | Lacoue-Labathe, Thomas | Vincx, Magda
Anthropogenic CO2 emissions are rapidly changing seawater temperature, pH and carbonate chemistry. This study compares the embryonic development under high pCO2 conditions across the south-north distribution range of the marine clam Limecola balthica in NW Europe. The combined effects of elevated temperature and reduced pH on hatching success and size varied strongly between the three studied populations, with the Gulf of Finland population appearing most endangered under the conditions predicted to occur by 2100. These results demonstrate that the assessment of marine faunal population persistence to future climatic conditions needs to consider the interactive effects of co-occurring physico-chemical alterations in seawater within the local context that determines population fitness, adaptation potential and the system resilience to environmental change.
Mostrar más [+] Menos [-]Seawater carbonate chemistry and hatching success and size of the marine clam Limecola balthica Texto completo
2018
Van Colen, Carl | Jansson, Anna | Saunier, Alice | Lacoue-Labathe, Thomas | Vincx, Magda
Anthropogenic CO2 emissions are rapidly changing seawater temperature, pH and carbonate chemistry. This study compares the embryonic development under high pCO2conditions across the south-north distribution range of the marine clam Limecola balthicain NW Europe. The combined effects of elevated temperature and reduced pH on hatching success and size varied strongly between the three studied populations, with the Gulf of Finland population appearing most endangered under the conditions predicted to occur by 2100. These results demonstrate that the assessment of marine faunal population persistence to future climatic conditions needs to consider the interactive effects of co-occurring physico-chemical alterations in seawater within the local context that determines population fitness, adaptation potential and the system resilience to environmental change.
Mostrar más [+] Menos [-]A cross-taxa study using environmental DNA/RNA metabarcoding to measure biological impacts of offshore oil and gas drilling and production operations Texto completo
2018
Laroche, Olivier | Wood, Susie A. | Tremblay, Louis A. | Ellis, Joanne I. | Lear, Gavin | Pochon, Xavier
Standardized ecosystem-based monitoring surveys are critical for providing information on marine ecosystem health. Environmental DNA/RNA (eDNA/eRNA) metabarcoding may facilitate such surveys by quickly and effectively characterizing multi-trophic levels. In this study, we assessed the suitability of eDNA/eRNA metabarcoding to evaluate changes in benthic assemblages of bacteria, Foraminifera and other eukaryotes along transects at three offshore oil and gas (O&G) drilling and production sites, and compared these to morphologically characterized macro-faunal assemblages. Bacterial communities were the most responsive to O&G activities, followed by Foraminifera, and macro-fauna (the latter assessed by morphology). The molecular approach enabled detection of hydrocarbon degrading taxa such as the bacteria Alcanivorax and Microbulbifer at petroleum impacted stations. Most identified indicator taxa, notably among macro-fauna, were highly specific to site conditions. Based on our results we suggest that eDNA/eRNA metabarcoding can be used as a stand-alone method for biodiversity assessment or as a complement to morphology-based monitoring approaches.
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