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Microplastic and charred microplastic in the Faafu Atoll, Maldives 全文
2018
Saliu, Francesco | Montano, Simone | Garavaglia, Maria Grazia | Lasagni, Marina | Seveso, Davide | Galli, Paolo
Microplastics are recognized as a growing threat for the marine environment that may even affect areas generally considered pristine. In this work we surveyed the microplastic contamination in the Faafu Atoll (Maldives, Indian Ocean) across twelve sampling station, located either inside or outside the reef rim. Sediments and seawater samples were collected. Despite the remoteness of the atoll, the scarce local population and low touristic annual afflux, the detected average abundance were 0.32 ± 0.15 particles/m3 in the surface water and 22.8 ± 10.5 particles/m2 in the beach sediments. Polymers identified through Fourier-Transform Infrared spectroscopy were mostly polyethylene, polypropylene, polystyrene, polyvinylchloride, polyethyleneterephtalate, and polyamide. Elastomeric residues and charred microparticles were also found. In particular, the charred microparticles were prevalently located nearby the inhabited island and they might be considered a peculiarity of the area, related to local practice of burning plastic waste at the shoreline.
显示更多 [+] 显示较少 [-]First assessment of the effectiveness of the international convention on the control of harmful anti-fouling systems on ships in Tunisia using imposex in Hexaplex trunculus as biomarker 全文
2018
Lahbib, Youssef | Abidli, Sami | Trigui-El Menif, Najoua
The global ban on the use of tributyltin (TBT) forced in September 2008 was ratified in Tunisia as late as June 2011. In this context, the present study aims to highlight the consequences of TBT contamination by monitoring 22 Tunisian sites before (2007) and after the ban (2012 and 2016) using as biomarker the occurrence of imposex in Hexaplex trunculus. From 2004 to 2016, complete recovery from imposex was reported in 11 sites. All average imposex indices calculated for each sampling year also decreased: imposex incidence from 61 to 27%, VDSI from 2 to 0.7, and RPLI from 15.7 to 1.6%. Ecological Quality Ratios (EQR) revealed that the sampling sites are in moderate to good ecological status. Overall, the present study confirms the effectiveness of the enacted legislation in reducing the impact of TBT pollution along the Tunisian coast.
显示更多 [+] 显示较少 [-]Sex may influence environmental diphenhydramine accumulation in Round Stingrays 全文
2018
Lyons, Kady | Burket, S Rebekah | Brooks, Bryan W.
Despite the amount of treated wastewater discharged into the Southern California Bight, few studies have examined pharmaceutical compounds in local biota. The Round Stingray (Urobatis halleri) was selected as a representative elasmobranch species to perform an exploratory study on environmental pharmaceutical exposure. Archived liver samples of males and females from juvenile to adult size classes from several locations (n = 53) were examined for 18 pharmaceutical and illicit drug compounds using isotope-dilution LC-MS/MS. Very few compounds were detected in stingray livers, with diphenhydramine as the only pharmaceutical above quantitation limits. Only stingrays collected from the urban site (mainland California) had detectable levels of diphenhydramine compared to no detections in reference stingrays (offshore island). Sex and sampling location substantially influenced both detection rate and concentrations. Our results suggest that aspects of species' ecology and physiology should be considered for future studies investigating pharmaceutical exposure in elasmobranchs.
显示更多 [+] 显示较少 [-]Influence of thermooxidative degradation on the in situ fate of polyethylene in temperate coastal waters 全文
2018
Karlsson, Therese M. | Hassellöv, Martin | Jakubowicz, Ignacy
Polyethylene is a commonly used polymer in plastic products and is often found as marine litter. Nevertheless there is limited knowledge about what happens to the material when it ends up in the sea. Polyethylene films were therefore thermally oxidised to four different levels of degradation. The films were then placed in stainless-steel cages in the sea off the Swedish west coast for 12 summer weeks. Subsamples were analysed with respect to biofouling, degradation and buoyancy. All levels showed a continued oxidation in the field. The pre-degraded films started fragmenting and the non-degraded films showed a decrease in tensile strain. All levels showed increased biofouling with higher presence of filamentous algae and bryozoans on pre-degraded materials. The density (kg·m−3) of the films was seen to increase slightly, and the apparent density for the pre-degraded films (density of the films with biofilm) showed a strong increase, which resulted in sinking.
显示更多 [+] 显示较少 [-]Pollution signature for temperate reef biodiversity is short and simple 全文
2018
Ling, S.D. | Davey, A. | Reeves, S.E. | Gaylard, S. | Davies, P.L. | Stuart-Smith, R.D. | Edgar, G.J.
Pollution increasingly impacts healthy functioning of marine ecosystems globally. Here we quantify concentrations of major pollutant types (heavy metals/sewage/petrochemicals/plastics) as accumulated within marine sediments on and/or immediately adjacent to shallow reefs for 42 sites spanning coastal population centres across south-eastern Australia. Gradients in pollutants were revealed, but few pollutants co-varied, while increasing wave exposure ostensibly diluted concentrations of all pollutants except microplastics. Examination of reef biodiversity indicators revealed that maximum size of fauna and flora, a key life-history parameter summarised by the Community shortness index, plus declining functional and species richness, were the most sensitive bioindicators of pollutants – for which heavy metals and nutrient-enrichment were most pervasive. Results indicate that assemblages of biogenic habitat formers and associated fauna collapse from “long and complicated” to “short and simplified” configurations in response to increasing pollution, and this community signature may form an effective bioindicator to track human-driven degradation.
显示更多 [+] 显示较少 [-]Marine introduced species in Australia, where to from here? A personal perspective from a practising taxonomist 全文
2018
Hutchings, Pat
While introduced marine species have been arriving in Australia for centuries, it was the advent of container shipping and the discharge of ballast water into Australian ports that highlighted the problem. A summary is provided of how Australia responded to this challenge and continues to. More recently there has been an acceptance that hull fouling is also an important vector of introductions. A major problem in Australia is distinguishing introduced species from as yet undescribed native species. This is a particular problem in northern Australia where the native fauna is poorly documented. Despite the economic and environmental threats posed by introduced species, the impetus to undertake expensive comprehensive surveys has declined and attention is now focusing on targeted surveys especially of known marine pest species and molecular data to identify introductions. Ongoing research is still needed to monitor other species identified as being introduced and their potential to become pests.
显示更多 [+] 显示较少 [-]Manure Phosphorus: Mobility in Soils and Management Strategies to Minimize Losses 全文
2018
Kumaragamage, D. | Akinremi, O.O.
Manure is a valuable source of plant nutrients; however, continuous application to soils may lead to accumulation of phosphorus (P), increasing the risk of P loss into waterways triggering freshwater eutrophication. This review paper summarizes and critically evaluates relevant research findings published within the last 5 years on manure P mobility in soils and management strategies to mitigate losses identifying future research needs. Past and recent research evidence on manure P mobilization and losses from soils have yielded inconsistent and often confounding results, because of the interactive effects of source factors and the existence of concurrent transport pathways. Although far from being conclusive, a few general trends are worth noting; P losses were greater with (a) increasing soluble P applied with manure, (b) vulnerable soils with limited P sorption capacity and/or susceptible to preferential flow/erosion, (c) conditions conducive to P release and transport, and (d) reduced soil-manure P interaction following application. Effective mitigating strategies included (a) generating low-P manure, (b) processing manure to reduce total and/or soluble P, and (c) adopting best management practices (BMPs) during and post-manure application. Future research should focus on a better understanding of the interactive effects of source factors on short- and long-term manure P loss via different transport pathways. Existing mitigation efforts and new directions should focus on reducing P buildup in soil by employing a combination of strategies during generation, processing, and application of manure, coupled with site- and time-specific BMPs selected based on the dominant pathway of P loss.
显示更多 [+] 显示较少 [-]Desalination of Water: a Review 全文
2018
Darre, NatashaC. | Toor, GurpalS.
PURPOSE OF REVIEW: In the face of rising water demands and dwindling freshwater supplies, alternative water sources are needed. Desalination of water has become a key to helping meet increasing water needs, especially in water-stressed countries where water obtained by desalination far exceeds supplies from the freshwater sources. RECENT FINDINGS: Recent technological advancements have enabled desalination to become more efficient and cost-competitive on a global scale. This has become possible due to the improvement in the materials used in membrane-based desalination, incorporation of energy-recovery devices to reduce electricity demands, and combining different desalination methods into hybrid designs. Further, there has been a gradual phasing-in of renewable energy sources to power desalination plants, which will help ensure the long-term sustainability of desalination. However, there are still challenges of reducing energy demands and managing waste products from the desalination to prevent adverse environmental effects. This article reviews the history, location, components, costs, and other facets of desalination and summarizes the new technologies that are set to improve the overall efficiency of the desalination process.
显示更多 [+] 显示较少 [-]A review of chemical-based sediment quality assessment methodologies for the marine environment 全文
2018
Birch, G.F.
This review of 19 chemical approaches used in assessing sediment quality are classified into empirical, mechanistic and sediment quality indices (SQI) groups. Empirical sediment quality guidelines (SQGs), based on matching chemical and biological-effects data and the mechanistic techniques, founded on equilibrium partitioning principals (EqP), are well established and most used. Empirical SQGs provide a useful screening tool to initially identify locations and chemicals of most concern, but are not regulatory criteria. The EqP approach is causally linked however, the scheme assumes porewater chemistry largely controls sediment toxicity. SQIs are not based on matching chemical-biological data and combine schemes with multiple narrative intents. The 41 SQGs reviewed show a considerable range in upper and lower guideline values. Grain size and organic content should be included into SQGs, however inclusion of suspended sediment into SQGs raises concerns. SQGs are built into decision-tree schemes with other lines-of-evidence and evaluated in a weight-of-evidence framework.
显示更多 [+] 显示较少 [-]Changes in the tissue concentrations of trace elements during the reproductive cycle of Noah's Ark shells (Arca noae Linnaeus, 1758) 全文
2018
Erk, Marijana | Ivanković, Dušica | Župan, Ivan | Čulin, Jelena | Dragun, Zrinka | Puljas, Sanja | Peharda, Melita
Concentrations of 23 trace elements (TEs; essential: Co, Cu, Fe, Mn, Mo, Se, V, Zn; non-essential: Ag, Al, As, Ba, Cd, Cr, Cs, Li, Ni, Pb, Rb, Sr, Ti, Tl, U) in whole soft tissues of Noah's Ark shell (Arca noae) were determined monthly during one year (March 2013–February 2014) at two sampling sites in the central part of the Eastern Adriatic Sea. Our aim was to detect the influence of reproductive cycle and changes in the environmental factors on the variabilities of TEs' contents. Higher concentrations of Pb, Ba, V, Mo, Mn and Fe were found at potentially contaminated site in Pašman channel, whereas higher concentrations of Tl, Ni, Li, Cr, Cd, Ti and Se were found at reference site in Nature Park Telašćica. Since several bioaccumulated TEs were associated to mean gonadal index, in TEs monitoring in A. noae, animal gonadal status has to be considered.
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