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Seasonal variation in the abundance of marine plastic debris in Banderas Bay, Mexico Full text
2019
Pelamatti, Tania | Fonseca-Ponce, Iliana A. | Rios-Mendoza, Lorena M. | Stewart, Joshua D. | Marín-Enríquez, Emigdio | Marmolejo-Rodriguez, Ana J. | Hoyos-Padilla, Edgar M. | Galván-Magaña, Felipe | González-Armas, Rogelio
A floating plastic monitoring program was conducted for two years on a weekly basis in Banderas Bay, Mexico. A total of 94 samples were collected from May 2016 to April 2018 in the southern part of the bay. Half (57%) of them contained plastic debris; 79% of it being <5 mm in length. Polypropylene and Polyethylene were the most abundant polymers, accounting for 45% and 43% of the plastic pieces (pp), respectively. The highest abundance of plastic pieces was found in July 2016, with a maximum of 0.3 pp/m³ found in one sample. The amount of floating plastics was significantly higher in the hurricane season compared to the dry season (p < 0.001). This suggests that rainfall may play a significant role in the offload of plastics from land-based sources into the bay.
Show more [+] Less [-]Influence of suspended mariculture on vertical distribution profiles of bacteria in sediment from Daya Bay, Southern China Full text
2019
Shi, Rongjun | Xu, Shumin | Qi, Zhanhui | Zhu, Qingzhi | Huang, Honghui | Weber, Felix
Mariculture is known to contribute to oxygen depletion, pH decline and accumulation of nutrients and organic matter in sediments. However, studies on the bacterial vertical distribution of mariculture area are very limited. The bacterial abundance in the non-culture site (3.8 ± 0.8 × 10⁹ copies g⁻¹) was significantly higher than that in the three mariculture sites (1.2 ± 0.2 × 10⁹ copies g⁻¹), and bacterial diversity in the non-culture site was significantly higher than that in fish cage-TF (p < 0.05). The vertical distribution profiles of bacteria in non-culture and oyster culture sites were similar but very different from that of fish cage-TF. In addition, significant downward trends in bacterial abundance and diversity were observed as sediment depth increased (p < 0.05), and the most relevant environmental factors were moisture content, total nitrogen, total organic carbon and carbon/nitrogen. The dominant bacterial phyla in sediment were Proteobacteria, Chloroflexi and Bacteroidetes.
Show more [+] Less [-]Heterotrophic consumption may mask increasing primary production fuelled by anthropogenic nutrient loading in the northern Arabian/Persian Gulf Full text
2019
Al-Said, Turki | Naqvi, S. Wajih A. | Ahmed, Ayaz | Madhusoodhanan, Rakhesh | Fernandes, Loreta | Kedila, Raziya | Almansouri, Hadeel | Rifāʻī, Khulūd | Al-Yamani, Faiza
Monthly measurements of nitrate, nitrite, ammonium and phosphate at three stations off Kuwait during 2002–2015 revealed considerable inter-annual variability, broadly corresponding to fluctuations in the Shatt-al-Arab River discharge, but a lack of secular increasing trend. Nutrient enrichment experiments during two seasons revealed nitrate uptake, chlorophyll build-up and growth of micro-phytoplankton, even in the presence of ammonium, provided the availability of phosphate. Primary production was mostly nitrogen limited, but anthropogenic nitrogen supply may eventually make it phosphorus limited, especially in summer and in the open Gulf. Anthropogenic nutrient inputs appear to have enhanced biological productivity of the northern Gulf, but heterotrophic consumption, indicated by high respiration rates, probably prevented accumulation of phytoplankton biomass, accounting for the observed lack of chlorophyll increase over the past three decades. Consequently high total organic carbon and emerging hypoxia in the Gulf may lead to expansion/intensification of the oxygen minimum zone of the Arabian Sea.
Show more [+] Less [-]Using solitary ascidians to assess microplastic and phthalate plasticizers pollution among marine biota: A case study of the Eastern Mediterranean and Red Sea Full text
2019
Vered, Gal | Kaplan, Aviv | Avisar, Dror | Shenkar, Noa
The interaction of microplastic (MP) with marine organisms is crucial for understanding the significant effect that MP and its additives may have on marine environments. However, knowledge regarding the magnitude of these pollutants in the Eastern Mediterranean Sea and the tropical Red Sea is still scarce. Here we examined the levels of phthalate acid esters (PAEs) and MP in Herdmania momus and Microcosmus exasperatus sampled along the Mediterranean and Red Sea coasts of Israel. High levels of dibutyl phthalate (DBP) and bis (2‑ethylhexyl) phthalate (DEHP) were found in ascidians at the majority of sampling sites, and MP particles were found in ascidians at all sites. As efficient filter-feeders and being widely-distributed, invasive ascidians present fundamental opportunities for the environmental monitoring of microplastic and its additives worldwide. The high levels of pollutants revealed emphasize the need for further research into the magnitude and effects of MP and PAEs in these regions.
Show more [+] Less [-]Oil pollution in the Eastern Arabian Sea from invisible sources: A multi-technique approach Full text
2019
Suneel, V. | Rao, V Trinadha | Suresh, Gopika | Chaudhary, Aditya | Vethamony, P. | Ratheesh, R.
Oil pollution in the Eastern Arabian Sea from invisible sources: A multi-technique approach Full text
2019
Suneel, V. | Rao, V Trinadha | Suresh, Gopika | Chaudhary, Aditya | Vethamony, P. | Ratheesh, R.
The Eastern Arabian Sea (EAS) is affected by oil pollution, as often evidenced by the presence of tarballs along the West Coast of India (WCI). Tarball samples collected during May 2017 along the Goa coast were subject to biomarker fingerprints, and the results matched with Bombay High (BH) oil fingerprints. The present study primarily aims at identifying the potential minor spill areas using Sentinel-imagery. Interestingly, repeated occurrence of oil spills detected at two locations, perfectly matched with BH platforms. The simulated Lagrangian trajectories also depict that tarball particles have originated from those detected locations. In 2017 alone, the quantity of spilled oil was estimated to be 129,392 l. However, spills detected offshore regions of Kachchh and Mangalore were found to be caused by ships. This is the first comprehensive study, tracking the oil pollution sources in the EAS through multi-technique approach - chemical, remote sensing and numerical modeling.
Show more [+] Less [-]Oil pollution in the Eastern Arabian Sea from invisible sources: A multi-technique approach Full text
2019
Suneel V. | Rao V.T. | Suresh G. | Chaudhary A. | Vethamony P. | Ratheesh R.
The Eastern Arabian Sea (EAS) is affected by oil pollution, as often evidenced by the presence of tarballs along the West Coast of India (WCI). Tarball samples collected during May 2017 along the Goa coast were subject to biomarker fingerprints, and the results matched with Bombay High (BH) oil fingerprints. The present study primarily aims at identifying the potential minor spill areas using Sentinel-imagery. Interestingly, repeated occurrence of oil spills detected at two locations, perfectly matched with BH platforms. The simulated Lagrangian trajectories also depict that tarball particles have originated from those detected locations. In 2017 alone, the quantity of spilled oil was estimated to be 129,392 l. However, spills detected offshore regions of Kachchh and Mangalore were found to be caused by ships. This is the first comprehensive study, tracking the oil pollution sources in the EAS through multi-technique approach - chemical, remote sensing and numerical modeling. - 2019 Elsevier Ltd | Scopus
Show more [+] Less [-]Monitoring of sessile and mobile epifauna – Considerations for non-indigenous species Full text
2019
Outinen, Okko | Forsström, Tiia | Yli-Rosti, Juho | Vesakoski, Outi | Lehtiniemi, Maiju
Monitoring of sessile and mobile epifauna – Considerations for non-indigenous species Full text
2019
Outinen, Okko | Forsström, Tiia | Yli-Rosti, Juho | Vesakoski, Outi | Lehtiniemi, Maiju
The present study aimed to develop monitoring methods for shallow water sessile and mobile epifauna with the main focus on enhancing the chance of early detection for new non-indigenous species (NIS) invasions. The field sampling was conducted between June and September in 2012, in the Archipelago Sea (Finland). The tested monitoring methods included baited traps that capture organisms and habitat collectors that provide habitat and refuges for organisms, as well as fouling plates. Catch efficiency of a trap/collector was defined as the number of NIS and all species caught, including their abundances. The American collector with oyster shells (habitat collector) caught the highest number of NIS, and their use is recommended in all places, where oyster shells are easily accessible. Sampling of all habitats of interest between 1 and 2 m depth is recommended with at least three habitat collectors per site.
Show more [+] Less [-]Monitoring of sessile and mobile epifauna – Considerations for non-indigenous species Full text
2019
Outinen, Okko | Forsström, Tiia | Yli-Rosti, Juho | Vesakoski, Outi | Lehtiniemi, Maiju
The present study aimed to develop monitoring methods for shallow water sessile and mobile epifauna with the main focus on enhancing the chance of early detection for new non-indigenous species (NIS) invasions. The field sampling was conducted between June and September in 2012, in the Archipelago Sea (Finland). The tested monitoring methods included baited traps that capture organisms and habitat collectors that provide habitat and refuges for organisms, as well as fouling plates. Catch efficiency of a trap/collector was defined as the number of NIS and all species caught, including their abundances. The American collector with oyster shells (habitat collector) caught the highest number of NIS, and their use is recommended in all places, where oyster shells are easily accessible. Sampling of all habitats of interest between 1 and 2 m depth is recommended with at least three habitat collectors per site. Highlights • Sampling of mobile and sessile epifauna with habitat collectors is recommended. • Habitat traps should provide attachment surfaces, habitats and refuges to organisms. • Sampling of all habitats present between 1 and 2 m depth is recommended. • Deployment of 3 collectors per site is suggested for routine coastal monitoring. • Timing and duration of sampling may differ significantly between geographical areas.
Show more [+] Less [-]Benthic community status and mobilization of Ni, Cu and Co at abandoned sea deposits for mine tailings in SW Norway Full text
2019
Schaanning, Morten Thorne | Trannum, Hilde Cecilie | Øxnevad, Sigurd | Ndungu, Kuria
Benthic community status and mobilization of Ni, Cu and Co at abandoned sea deposits for mine tailings in SW Norway Full text
2019
Schaanning, Morten Thorne | Trannum, Hilde Cecilie | Øxnevad, Sigurd | Ndungu, Kuria
During 1960–94 tailings from an ilmenite mine in southwest Norway were placed in sea deposits in a sheltered fjord and a more exposed coastal basin. In 2015 both deposit sites were sampled to assess the state of metal contamination and macrobenthic communities 20–30 years after deposition was ended. The results showed that nickel and copper still exceeded environmental quality standards in sediment and pore water from the 0–1 cm layer, and fluxes of nickel, copper and cobalt to the overlying water was high compared to adjacent reference stations. Fauna communities were classified as good, but moderate disturbance was recorded along an environmental gradient defined by depth and tailings-induced parameters such as particle size and copper. The results were interpreted in terms of current discharges, biological sediment reworking and near-surface leaching of metal sulphides. No evidence was found for recycling of metals from tailings buried below the bioturbated surface layer.
Show more [+] Less [-]Benthic community status and mobilization of Ni, Cu and Co at abandoned sea deposits for mine tailings in SW Norway Full text
2019
Schaanning, Morten Thorne | Trannum, Hilde Cecilie | Øxnevad, Sigurd | Ndungu, Kuria
During 1960–94 tailings from an ilmenite mine in southwest Norway were placed in sea deposits in a sheltered fjord and a more exposed coastal basin. In 2015 both deposit sites were sampled to assess the state of metal contamination and macrobenthic communities 20–30 years after deposition was ended. The results showed that nickel and copper still exceeded environmental quality standards in sediment and pore water from the 0–1 cm layer, and fluxes of nickel, copper and cobalt to the overlying water was high compared to adjacent reference stations. Fauna communities were classified as good, but moderate disturbance was recorded along an environmental gradient defined by depth and tailings-induced parameters such as particle size and copper. The results were interpreted in terms of current discharges, biological sediment reworking and near-surface leaching of metal sulphides. No evidence was found for recycling of metals from tailings buried below the bioturbated surface layer. | publishedVersion
Show more [+] Less [-]Developing conceptual models that link multiple ecosystem services to ecological research to aid management and policy, the UK marine example Full text
2019
Broszeit, Stefanie | Beaumont, Nicola J. | Hooper, Tara L. | Somerfield, Paul J. | Austen, Melanie C.
Our understanding of ecological processes that lead to ecosystem services is still evolving but ecological research aims to understand the linkages between the ecosystem and services. These linkages can affect trade-offs between different ecosystem services. Understanding these linkages, by considering multiple ecosystem services simultaneously supports management of the environment and sustainable use of resources. The UK marine environment is relatively data rich, yet the links between ecosystem and several ecosystem services and linkages between services are poorly described. A workshop with 35 marine scientists was used to create a conceptual model that links ecosystem components and key processes to four services they provide and to highlight trade-offs between them. The model was subsequently further developed to include pressures and mitigating management measures. The models are discussed in terms of their application to marine data to facilitate evidence-based marine management and their usefulness to communicate management measures with managers and stakeholders.
Show more [+] Less [-]Effects of shrimp pond effluents on stocks of organic carbon, nitrogen and phosphorus in soils of Kandelia obovata forests along Jiulong River Estuary Full text
2019
Global aquaculture discharges are typical anthropogenic carbon and nutrient sources to nearby mangrove forests. In this study, we quantified total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP) stocks (0–50 cm) in soils from three sites of Kandelia obovata forests with different shrimp-pond discharge histories of 0, 8 and 14 years (i.e. 0DK, 8DK and 14DK, respectively). Results showed that shrimp pond effluents increased soil TOC densities at 8DK. TP densities gradually increased with discharge histories, whereas TN densities were similar between 8DK and 14DK. Besides, IsoSource analyses demonstrated that the high δ¹³C values of shrimp pond effluents contributed 30.00%–33.60% of mangrove soil TOC at 0–10 cm depth. These results suggested that shrimp pond effluents altered soil TOC, TN and TP stocks and added carbon source to mangrove soils, which was related to discharge histories and soil depth. Moreover, the discharge changed carbon and nutrient patterns, which warrant attention.
Show more [+] Less [-]Cost-effective monitoring of large micro- and meso-litter in tidal and flood accumulation zones at south-western Baltic Sea beaches Full text
2019
Often, beach litter monitoring strategies focus only on macro-litter (>25 mm) and do not distinguish between litter left at beaches and litter washed up onshore. We tested inexpensive and user-friendly methods to examine meso-litter (5–25 mm) and large micro-litter (2–5 mm) washed up on German sandy beaches and evaluated our methods regarding the requirements of the Marine Strategy Framework Directive. With a sieve accumulation zone monitoring method, tested 41 times, we found 0.2–21.2 litter pieces/m² (⌀ 5.3 pieces/m² ± 8.9). With a bare eye accumulation zone monitoring method, tested 10 times, at other beaches, 9.1–65.6 litter pieces/m² (⌀ 31.8 pieces/m² ± 15.7) were found. Both methods are inexpensive, useful for volunteers, and can be carried out quickly, but are also limited, as they cannot be used regularly. A tested webcam and a modified Braun-Blanquet method turned out to be less suitable.
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