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The management in response to marine oil spill from ships in China: A systematic review Texte intégral
2015
Xiong, Shangao | Long, Hualou | Tang, Guoping | Wan, Jun | Li, Hongyuan
Historical trends about marine ship-source oil spill incidents from 1990 to 2010 in China were analyzed, and it provided an overview of the status quo of China’s management in response to marine oil spill from ships. The Chinese government has issued a series of laws on marine environmental protection since 1982, and promulgated many regulations to prevent and tackle ship-source oil spill. At present, the oil spill emergency response system established in China has five levels: the national level, sea level, provincial level, port level, and ship level. China has demonstrated its ability to control and remove small-scale oil spill from ships in port area and near-shore coastal waters, and also paid attention to related research and development projects. Although China has made significant progress in managing shipping oil spill, challenges still exist, including strengthening oil spill emergency cooperation, enhancing China’s response capability, and improving relevant research and development projects.
Afficher plus [+] Moins [-]Multivariate and geo-spatial approach for seawater quality of Chidiyatappu Bay, south Andaman Islands, India Texte intégral
2015
Jha, Dilip Kumar | Vinithkumar, Nambali Valsalan | Sahu, Biraja Kumar | Dheenan, Palaiya Sukumaran | Das, Apurba Kumar | Begum, Mehmuna | Devi, Marimuthu Prashanthi | Kirubagaran, Ramalingam
Chidiyatappu Bay is one of the least disturbed marine environments of Andaman & Nicobar Islands, the union territory of India. Oceanic flushing from southeast and northwest direction is prevalent in this bay. Further, anthropogenic activity is minimal in the adjoining environment. Considering the pristine nature of this bay, seawater samples collected from 12 sampling stations covering three seasons were analyzed. Principal Component Analysis (PCA) revealed 69.9% of total variance and exhibited strong factor loading for nitrite, chlorophyll a and phaeophytin. In addition, analysis of variance (ANOVA-one way), regression analysis, box-whisker plots and Geographical Information System based hot spot analysis further simplified and supported multivariate results. The results obtained are important to establish reference conditions for comparative study with other similar ecosystems in the region.
Afficher plus [+] Moins [-]Mercury concentrations in Atlantic bottlenose dolphins (Tursiops truncatus) inhabiting the Indian River Lagoon, Florida: Patterns of spatial and temporal distribution Texte intégral
2015
Schaefer, Adam M. | Titcomb, Elizabeth Murdoch | Fair, Patricia A. | Stavros, Hui-Chen W. | Mazzoil, Marilyn | Bossart, Gregory D. | Reif, John S.
Bottlenose dolphins (Tursiops truncatus) inhabiting the Indian River Lagoon, FL (IRL) have tissue mercury concentrations among the highest reported worldwide. Analysis of total mercury (THg) concentrations in blood collected between 2003 and 2012 showed a significant linear decrease over time (p=0.04). Significant differences in the spatial distribution of THg in resident IRL dolphins were also observed with a general gradient in concentration from north to south. Evaluation of local biogeochemistry and accumulation of mercury in prey species is needed to better understand factors influencing the distribution of Hg in the apex predator. Analyses of temporal and spatial patterns of exposure to THg in this sentinel species may have implications for both ecosystem and public health in the region.
Afficher plus [+] Moins [-]Distribution and assessment of heavy metals off the Changjiang River mouth and adjacent area during the past century and the relationship of the heavy metals with anthropogenic activity Texte intégral
2015
Hu, Gang | Bi, Shipu | Xu, Gang | Zhang, Yong | Mei, Xi | Li, Anchun
Forty-three surface sediment samples and one gravity core obtained from the offshore area of the Changjiang River were analyzed for selected heavy metals (Cu, Pb, Zn, Cd, As, Hg) to evaluate the spatial distribution and potential ecological risk during the last century. The results indicated that the sediments are composed of silty sand, sandy silt and silt and were deposited in a relatively stable environment over the last century. The studied marine sediments are fine and easily adsorb heavy metals from aquatic systems. The heavy metal concentrations were found to be enriched in the sediments and were generally closely related to anthropogenic activities. However, the data analysis demonstrated that the levels of heavy metal contamination were below background values during the last century, indicating low ecological risk. Spatially, a higher concentration was found at the entrance to the Changjiang River, while it decreased to the northeast. The vertical distribution of contamination levels and ecological risk can be divided into four periods based on the downcore variation in heavy metals: pre-1940s, 1940s–1970s, 1970s–1990s and the late 1990s to the present. These conclusions form the basis for implementing appropriate policies to protect marine sediment quality.
Afficher plus [+] Moins [-]Anthropogenic impacts on meiobenthic Ostracoda (Crustacea) in the moderately polluted Kasado Bay, Seto Inland Sea, Japan, over the past 70 years Texte intégral
2015
Irizuki, Toshiaki | Ito, Hisayo | Sako, Megumi | Yoshioka, Kaoru | Kawano, Shigenori | Nomura, Ritsuo | Tanaka, Yuichiro
Two sediment cores were obtained from Kasado Bay, a moderate-polluted enclosed bay in Japan, to examine anthropogenic impacts on Ostracoda over the past ca. 70years. We analyzed ostracode abundance and diversity, grain size, and CHN, and used 210Pb and 137Cs as the dating method. The present study showed that cross-plot comparisons of ostracode abundance and each environmental factor, based on sediment core data, could be used to identify ostracode species as indicators for anthropogenic influences. Ostracode abundance reflected mainly the changes that had occurred in total organic carbon content in sediments related to eutrophication, but heavy metal concentration did not directly influence several ostracode abundance in the bay. Environmental deterioration because of eutrophication started in the 1960s. The regulations regarding the chemical oxygen demand in waters introduced in the 1980s probably influence ostracode abundance for certain species in this period. Currently, Kasado Bay is not experiencing severe degradation.
Afficher plus [+] Moins [-]Bio-indicator bacteria & environmental variables of the coastal zones: The example of the Güllük Bay, Aegean Sea, Turkey Texte intégral
2015
Kalkan, Samet | Altuğ, Gülşen
In this study bio-indicator bacteria and environmental variable parameters were investigated in the coastal areas of the Güllük Bay, Aegean Sea, Turkey. The seawater samples which were taken from surface (0–30cm) were tested regarding total and fecal coliform, streptococci and nutrients from May to February in 2012–2013. The primary hydrographic parameters were recorded using multiparameter (YSI 556) in situ at the sampling stations. The highest fecal pollution stress and indicator bacteria values were observed in the period between June and August. The finding showed that bacterial pollution sources of the study area, especially in the summer season, under the control of increasing anthropogenic activities. The finding showed that terrestrial pollution sources carry a potential risk for public and ecosystem health and the sustainable use of living sources. Precautions should be formulated and put into action immediately in order to protect the region from bacteriological risks.
Afficher plus [+] Moins [-]Comprehensive assessment of coastal eutrophication in Taiwan and its implications for management strategy Texte intégral
2015
Liu, Dagang | Chen, Ping | Chen, Hou-Yu
Due to the rapid population growth, anthropogenic activities result in agricultural, industrial, and urban diffuse runoffs that elevate the level of nutrients such as nitrogen and phosphorus in coastal waters. Currently there is no integrated analysis for coastal eutrophication in Taiwan. A comprehensive analysis of the coastal eutrophic status was performed in this study based on decade-long coastal water quality monitoring data from Taiwan’s Environmental Protection Administration. A 3-tiered monitoring strategy is recommended based on the severity of the current eutrophication state. Results indicate that the most problematic area of coastal eutrophication is located in the estuary of the Donggang River (DGR) and its adjacent coastal waters, i.e., the Kao-Ping mouth (KPM) and Dapeng Bay (DPB) in south-western Taiwan. With a worsening eutrophic status, these areas demand intensive monitoring and research with higher spatial and temporal resolutions to evaluate the stresses of nutrient forcing and predict possible future responses.
Afficher plus [+] Moins [-]Marine litter in the upper São Vicente submarine canyon (SW Portugal): Abundance, distribution, composition and fauna interactions Texte intégral
2015
Oliveira, Frederico César Barbosa de | Monteiro, Pedro | Bentes, Luis | Henriques, Nuno Sales | Aguilar Melantzón, Ricardo | Gonçalves, Jorge M.S.
Marine litter has become a worldwide environmental problem, tainting all ocean habitats. The abundance, distribution and composition of litter and its interactions with fauna were evaluated in the upper S. Vicente canyon using video images from 3 remote operated vehicle exploratory dives. Litter was present in all dives and the abundance was as high as 3.31 items100m−1. Mean abundance of litter over rock bottom was higher than on soft substrate. Mean litter abundance was slightly higher than reported for other canyons on the Portuguese margin, but lower in comparison to more urbanized coastal areas of the world. Lost fishing gear was the prevalent type of litter, indicating that the majority of litter originates from maritime sources, mainly fishing activity. Physical contact with sessile fauna and entanglement of specimens were the major impacts of lost fishing gear. Based on the importance of this region for the local fishermen, litter abundance is expected to increase.
Afficher plus [+] Moins [-]Molluscan subfossil assemblages reveal the long-term deterioration of coral reef environments in Caribbean Panama Texte intégral
2015
Cramer, Katie L. | Leonard-Pingel, Jill S. | Rodríguez, Félix | Jackson, Jeremy B.C.
Caribbean reef corals have declined sharply since the 1980s, but the lack of prior baseline data has hindered identification of drivers of change. To assess anthropogenic change in reef environments over the past century, we tracked the composition of subfossil assemblages of bivalve and gastropod mollusks excavated from pits below lagoonal and offshore reefs in Bocas del Toro, Panama. The higher prevalence of (a) infaunal suspension-feeding bivalves and herbivorous and omnivorous gastropods in lagoons and (b) epifaunal and suspension-feeding bivalves and carnivorous and suspension-feeding gastropods offshore reflected the greater influence of land-based nutrients/sediments within lagoons. Temporal changes indicated deteriorating environmental conditions pre-1960 in lagoons and post-1960 offshore, with offshore communities becoming more similar to lagoonal ones since 1960. Relative abundances of dominant bivalve species tracked those of their coral hosts, revealing broader ecosystem effects of coral community change. The nature and timing of changes implicate land-based runoff in reef deterioration.
Afficher plus [+] Moins [-]A case study on effects of oil spills and tar-ball pollution on beaches of Goa (India) Texte intégral
2015
Rekadwad, Bhagwan N | Khobragade, Chandrahasya N
This paper reports the impact of oil spills and tar-ball pollution on the coastal ecosystem of Goa. The factors responsible for degrading the marine ecosystem of the Goan coastline are analyzed. Uncontrolled activities were found to degrade the marine and coastal biodiversity, in turn polluting all beaches. This had a direct impact on the Goan economy through a decline in tourism. The government must adopt the necessary control measures to restore Goan beaches and the surrounding coastal areas.
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