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Questionnaire-based survey to managers of 101 wastewater treatment plants in Greece confirms their potential as plastic marine litter sources
2018
Mourgkogiannis, N. | Kalavrouziotis, I.K. | Karapanagioti, H.K.
Marine pollution by plastics and microplastics (plastic particles 1 nm to 5 mm) is a recognized environmental issue. There are a few studies measuring the concentration of microplastics in the wastewater treatment plants (WWTP) effluent to the sea. Although microplastic concentrations are low in the WWTP effluent, the actual amount of microplastic ending up in the marine environment through WWTPs is quite significant. The present study is an extensive questionnaire-based survey to untrained managers of 101 WWTPs located all over Greece reporting visually-observed plastic items. 94 of the WWTPs have screens with gaps larger than 5 mm. This suggests that microplastics are passing through pretreatment to the main WWTP. In addition, 89 of the WWTP managers observed plastics in different tanks of the WWTPs. Cotton swab sticks are identified as the most common plastic found in WWTPs and the surrounding marine and coastal areas of the effluent pipes.
Show more [+] Less [-]Potential ecological risk of heavy metal contamination in sediments and macrobenthos in coastal wetlands induced by freshwater releases: A case study in the Yellow River Delta, China
2016
Li, Ming | Yang, Wei | Sun, Tao | Jin, Yuwan
We investigated the nine heavy metal contents in the sediments and macrobenthos of the Yellow River Delta Wetlands using three experimental areas that received freshwater releases and one reference area that did not. Heavy metal contents, the single-factor contamination index (SFCI), the metal contamination index (MCI), and the biota-sediment accumulation factor (BSAF) were used to evaluate the potential ecological risk and bioaccumulation. We found that As exceeded the national standard value by more than 50%, and that the ranges of SFCI for each metal were generally larger in autumn than in spring. MCI showed no clear pattern, but the BSAF results suggest that Cd bioaccumulates from sediments to macrobenthos. Pollution-resistant species such as Corophium sinense, Chironomus sp., and Einfeldia sp. became dominant in the areas receiving freshwater releases, and provide direct evidence of ecological risk in the wetlands. Our results provide preliminary information to guide managers for ecological risk assessments.
Show more [+] Less [-]Oil spill impacts on mangroves: Recommendations for operational planning and action based on a global review
2016
Duke, Norman C.
Mangrove tidal wetland habitats are recognised as highly vulnerable to large and chronic oil spills. This review of current literature and public databases covers the last 6 decades, summarising global data on oil spill incidents affecting, or likely to have affected, mangrove habitat. Over this period, there have been at least 238 notable oil spills along mangrove shorelines worldwide. In total, at least 5.5milliontonnes of oil has been released into mangrove-lined, coastal waters, oiling possibly up to around 1.94millionha of mangrove habitat, and killing at least 126,000ha of mangrove vegetation since 1958. However, there were assessment limitations with incomplete and unavailable data, as well as unequal coverage across world regions. To redress the gaps described here in reporting on oil spill impacts on mangroves and their recovery worldwide, a number of recommendations and suggestions are made for refreshing and updating standard operational procedures for responders, managers and researchers alike.
Show more [+] Less [-]Environmental conditions influence tissue regeneration rates in scleractinian corals
2015
Sabine, Alexis M. | Smith, Tyler B. | Williams, Dana E. | Brandt, Marilyn E.
Natural and anthropogenic factors may influence corals’ ability to recover from partial mortality. To examine how environmental conditions affect lesion healing, we assessed several water quality parameters and tissue regeneration rates in corals at six reefs around St. Thomas, US Virgin Islands. We hypothesized that sites closer to developed areas would have poor water quality due to proximity to anthropogenic stresses, which would impede tissue regeneration. We found that water flow and turbidity most strongly influenced lesion recovery rates. The most impacted site, with high turbidity and low flow, recovered almost three times slower than the least impacted site, with low turbidity, high flow, and low levels of anthropogenic disturbance. Our results illustrate that in addition to lesion-specific factors known to affect tissue regeneration, environmental conditions can also control corals’ healing rates. Resource managers can use this information to protect low-flow, turbid nearshore reefs by minimizing sources of anthropogenic stress.
Show more [+] Less [-]Coral reef baselines: How much macroalgae is natural?
2014
Bruno, John F. | Precht, William F. | Vroom, Peter S. | Aronson, Richard B.
Identifying the baseline or natural state of an ecosystem is a critical step in effective conservation and restoration. Like most marine ecosystems, coral reefs are being degraded by human activities: corals and fish have declined in abundance and seaweeds, or macroalgae, have become more prevalent. The challenge for resource managers is to reverse these trends, but by how much? Based on surveys of Caribbean reefs in the 1970s, some reef scientists believe that the average cover of seaweed was very low in the natural state: perhaps less than 3%. On the other hand, evidence from remote Pacific reefs, ecological theory, and impacts of over-harvesting in other systems all suggest that, historically, macroalgal biomass may have been higher than assumed. Uncertainties about the natural state of coral reefs illustrate the difficulty of determining the baseline condition of even well studied systems.
Show more [+] Less [-]Early steps for successful management in small-scale fisheries: An analysis of fishers', managers' and scientists' opinions preceding implementation
2018
Wallner-Hahn, Sieglind | Torre-Castro, Maricela de la
This study analyzes fishers', managers' and scientists' opinions on management measures to facilitate the initiation of management processes towards more sustainable small-scale seagrass fisheries in Zanzibar, Tanzania. The results show that most fishers and managers agreed on the need to include seagrasses specifically in future management. There was further agreement on dragnets being the most destructive gears, and the use of dragnets being a major threat to local seagrass ecosystems. Gear restrictions excluding illegal dragnets were the favored management measure among fishers. Differences between fishers and managers were found concerning seaweed farming, eutrophication and erosion being potential threats to seagrass meadows. A majority of the interviewed fishers were willing to participate in monitoring and controls, and most fishers thought that they themselves and their communities would benefit the most from establishing seagrass management. Co-managed gear restrictions and the inclusion of different key actos in the management process including enforcement are promising starting points for management implementation.
Show more [+] Less [-]Challenges in rendering Coral Triangle habitat richness in remotely sensed habitat maps: The case of Bunaken Island (Indonesia)
2018
Ampou, Eghbert Elvan | Ouillon, Sylvain | Andréfouët, Serge
The Coral Triangle is the epicenter of marine biodiversity, yet the numbers of habitats that can be found on coral reefs remain poorly described. First surveys for habitat mapping in Indonesia revealed a high number of habitats (>150) even for structurally simple reefs. To be able to represent all these habitats, typical habitat mapping procedures and performances are poorly effective even using very high resolution satellite images. Using Bunaken Island (North Sulawesi, Indonesia) as a case study, we devised a way to maintain all the in situ habitat information in remote sensing habitat map products without loss and with mapping procedures based on photo-interpretation. The result is a product which is consistent with a per-polygon fuzzy classification. As such, it is a complex product that meets our habitat representation goal, but its complexity can also limit its immediate use by managers and conservation planners when analyses per habitat are needed.
Show more [+] Less [-]Boat anchoring pressure on coastal seabed: Quantification and bias estimation using AIS data
2017
Deter, Julie | Lozupone, Xavier | Inacio, Adrien | Boissery, Pierre | Holon, Florian
Global shipping is economically important, but has many adverse environmental effects. Anchoring contributes greatly to this adverse impact, as it is responsible for mechanical disturbance of highly sensitive marine habitats. Recovery of these ecosystems is limited by slow regrowth. Anchoring pressure on coastal seabed habitats was estimated using AIS (Automatic Identification System) data along 1800km of Mediterranean coastline between 2010 and 2015. A comparison with field observations showed that these results were most consistent for large boats (>50m). An analysis of AIS data coupled with a seabed map showed that around 30% of the habitats between 0 and −80m exhibited anchoring pressure. Posidonia oceanica seagrass beds were the most impacted habitat in terms of duration. This methodology efficiently estimates spatial and temporal anchoring pressure principally due to large boats and should interest managers of marine protected areas as much as coastline managers.
Show more [+] Less [-]A Review of Non-Acoustic Measures to Handle Community Response to Noise around Airports
2017
Asensio, C. | Gasco, L. | de Arcas, G.
It seems obvious that the noise levels in local communities surrounding airports influences the level of acceptance of an airport. What is not so evident is the effect of non-acoustic factors that increase the societal rejection, like the lack of sensitivity and empathy from the authorities and airport managers, the lack of trust in them, the lack of information and transparency, the perception of being excluded from the decision making and so on. Complementary to the traditional strategies based on the reduction of noise exposure, a community engagement and involvement approach brings new possibilities to manage noise around airports, trying to exploit the non-acoustic factors that have negatively affected the community response. Building trust among the stakeholders is a key factor in this strategy, and it must be based on a long-term, honest, and transparent two-way communication. In the last decade, the huge growth of the information and communication technologies has opened new opportunities that the aviation organizations and stakeholders are starting to explore in depth trying to reduce the degree of rejection of the airport, which may compromise the utilization of existing and future infrastructure. In this review, we make a short introduction on aircraft noise health effects, to focus annoyance and the influence that non-acoustic factors on it. Then, we describe the basis of community engagement as a parallel approach to mitigate noise issues around airports, setting the focus on the noise metrics and the involvement techniques that must be implemented to engage the community.
Show more [+] Less [-]Rapid assessment of target species: Byssate bivalves in a large tropical port
2016
Rapid assessment sampling for target species is a fast cost-effective method aimed at determining the presence, abundance and distribution of alien and native harmful aquatic organisms and pathogens that may have been introduced by shipping. In this study, the method was applied within a large tropical port expected to have a high species diversity. The port of Kaohsiung was sampled for bivalve molluscan species that attach using a byssus. Such species, due to their biological traits, are spread by ships to ports worldwide. We estimated the abundance and distribution range of one dreissenid (Mytilopsis sallei) and four mytilids (Brachidontes variabilis, Arcuatula senhousa, Mytilus galloprovincialis, Perna viridis) known to be successful invaders and identified as potential pests, or high-risk harmful native or non-native species. We conclude that a rapid assessment of their abundance and distribution within a port, and its vicinity, is efficient and can provide sufficient information for decision making by port managers where IMO port exemptions may be sought.
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