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Meiofauna and its sedimentary environment as an integrated indication of anthropogenic disturbance to sandy beach ecosystems Full text
2014
Sun, Xinyu | Zhou, Hong | Hua, Er | Xu, Shuhui | Cong, Bingqing | Zhang, Zhinan
The accuracy and applicability of the Nematode/Copepod index (N/C) in monitoring the effects of environmental disturbances is controversial. In this study, we used an integrated approach that includes both meiofauna and the sedimentary environment to demonstrate a tourism-induced disturbance gradient among sampled beaches. We also analysed the relationships between meiofauna and environmental factors. The results showed that disturbed beaches were characterised by high values of meiofauna abundance, chlorophyll a content, total organic carbon content and N/C but lower levels of dissolved oxygen. The chlorophyll a and dissolved oxygen contents were found to be the most important factors for explaining the disturbance gradient amongst the beaches. The N/C index had a positive relationship with chlorophyll a and a negative relationship with dissolved oxygen. There was no significant relationship between N/C index and total organic carbon content.
Show more [+] Less [-]A review of oil, dispersed oil and sediment interactions in the aquatic environment: Influence on the fate, transport and remediation of oil spills Full text
2014
Gong, Yanyan | Zhao, Xiao | Cai, Zhengqing | O’Reilly, S.E. | Hao, Xiaodi | Zhao, Dongye
The 2010 Deepwater Horizon oil spill has spurred significant amounts of researches on fate, transport, and environmental impacts of oil and oil dispersants. This review critically summarizes what is understood to date about the interactions between oil, oil dispersants and sediments, their roles in developing oil spill countermeasures, and how these interactions may change in deepwater environments. Effects of controlling parameters, such as sediment particle size and concentration, organic matter content, oil properties, and salinity on oil–sediment interactions are described in detail. Special attention is placed to the application and effects of oil dispersants on the rate and extent of the interactions between oil and sediment or suspended particulate materials. Various analytical methods are discussed for characterization of oil–sediment interactions. Current knowledge gaps are identified and further research needs are proposed to facilitate sounder assessment of fate and impacts of oil spills in the marine environment.
Show more [+] Less [-]Description of a Multimetric Phytoplankton Index (MPI) for the assessment of transitional waters Full text
2014
Facca, Chiara | Bernardi Aubry, Fabrizio | Socal, Giorgio | Ponis, Emanuele | Acri, Francesco | Bianchi, Franco | Giovanardi, Franco | Sfriso, Adriano
A Multimetric Phytoplankton Index (MPI) is proposed to support management policies for the assessment of transitional ecosystems and the implementation of the European Water Framework Directive. The MPI incorporates Hulburt’s dominance index, bloom frequency and Menhinick’s diversity index, calculated on the basis of phytoplankton species composition.Chlorophyll a concentrations were also included, to provide biomass data and to guarantee continuity and comparison with past evaluations. The MPI was calculated by averaging the ratios of the resulting values of each metric to those of a reference site characterised by low anthropogenic impact.The MPI was set up using data from over a 10-year period in several stations in Venice Lagoon (North-western Adriatic region), a highly valuable and heterogeneous transitional environment, subject to significant anthropogenic pressures. The dataset included physico-chemical data, nutrient and contaminant concentrations. Statistical analyses allowed us to gauge the MPI’s responses to anthropogenic pressures and to verify its reliability.
Show more [+] Less [-]Spatial distribution and ecological risk of polychlorinated biphenyls in sediments from Qinzhou Bay, Beibu Gulf of South China Full text
2014
Zhang, Jinlian | Li, Yuanyuan | Wang, Yinghui | Zhang, Yuanyuan | Zhang, Dan | Zhang, Ruijie | Li, Jun | Zhang, Gan
The residual level of polychlorinated biphenyls (PCBs) was determined in the surface sediments collected from the Qinzhou Bay, Beibu Gulf of Southern China. The results showed that the total concentration of PCBs ranged from 1.62 to 62.63ng/g dry wt, with a mean of 9.87ng/g dry wt. Generally, the average PCBs concentrations in three sample groups descended in this order: inner bay>outer bay>rivers. On a mean level, with respect to the PCBs homologue profiles, the analysis suggested that tetrachlorinated biphenyls was the most abundant PCB, followed by hexachlorinated biphenyls, pentachlorinated biphenyls. PCB profiles varied according to the nature of the site and its proximity to the sources. PCA with multiple linear regression analysis indicated that Aroclor products contributed to the PCBs in Qinzhou Bay. Risk assessments conducted on the levels indicated that PCBs in sediments of Qinzhou Bay posed no significant risk to human health.
Show more [+] Less [-]Spatial and temporal dynamics in macrobenthos during recovery from salmon farm induced organic enrichment: When is recovery complete? Full text
2014
Keeley, Nigel B. | Macleod, Catriona K. | Hopkins, Grant A. | Forrest, Barrie M.
This study documents eight years of benthic recovery at a highly impacted salmon farm. Substantial recovery occurred in the first 2years, and was assessed to be complete after ∼5years. However, minor differences were still evident, along with some on-going benthic instability, attributable to medium-scale spatial movements and successional patterns of macrobenthos. Quantifying the endpoint of ‘recovery’ proved challenging due to: lack of a widely accepted definition, inherent variability in recovering sediments, differing trajectories of impact and reference sites, and statistical challenges. More complex biotic indices and metrics incorporating multiple variables were the most robust indicators. Statistical tests for ‘parallelism’ in the trajectories of Cage and Reference sites proved useful, but results were contingent upon how the method was applied, and should therefore be used in conjunction with data-visualisation methods. The study highlights the importance of a predetermined recovery endpoint, and using multiple indicators and a weight-of-evidence assessment approach.
Show more [+] Less [-]The application of a carrier-based bioremediation strategy for marine oil spills Full text
2014
Sheppard, Petra J. | Simons, Keryn L. | Adetutu, Eric M. | Kadali, Krishna K. | Juhasz, Albert L. | Manefield, Mike | Sarma, Priyangshu M. | Lal, Banwari | Ball, A. S.
The application of recycled marine materials to develop sustainable remediation technologies in marine environment was assessed. The remediation strategy consisted of a shell carrier mounted bacterial consortium composed of hydrocarbonoclastic strains enriched with nutrients (Bioaug SC). Pilot scale studies (5000l) were used to examine the ability of Bioaug-SC to degrade weathered crude oil (10gl−1; initially 315,000±44,000mgl−1) and assess the impacts of the introduction and biodegradation of oil. Total petroleum hydrocarbon mass was effectively reduced by 53.3 (±5.75)% to 147,000 (±21,000) mgl−1 within 27weeks. 16S rDNA bacterial community profiling using Denaturant Gradient Gel Electrophoresis revealed that cyanobacteria and Proteobacteria dominated the microbial community. Aquatic toxicity assessment was conducted by ecotoxicity assays using brine shrimp hatchability, Microtox and Phaeodactylum tricornutum. This study revealed the importance of combining ecotoxicity assays with oil chemistry analysis to ensure safe remediation methods are developed.
Show more [+] Less [-]Amount and type of derelict gear from the declining black pearl oyster aquaculture in Ahe atoll lagoon, French Polynesia Full text
2014
Andréfouët, Serge | Thomas, Yoann | Lo, Cedrik
Pearl oyster aquaculture is a major activity in French Polynesia atoll lagoons. After the economic decline that characterized the last decade, concerns recently rose about discarded installations and materials that supported aquaculture practices and by facilities abandoned after they had to close their activities. In May 2013, a first inventory of the type and amount of pearl farms derelict gear (PFDG) was achieved on 47 sites in Ahe lagoon. Surveys were conducted within and outside the boundaries of aquaculture concessions. Twenty types of PFDG littered the lagoon floor and the water column. The most impacted areas were near abandoned grafting houses with up to nine types of PFDG. Forty-five percent of the sites were impacted, including outside concessions. While management authorities are fully aware of the problem, this first assessment is a wake-up call to stimulate the cleaning of lagoons, enhance awareness among farmers, and identify potential ecological consequences on lagoon ecosystems.
Show more [+] Less [-]Environmental accounting for Arctic shipping – A framework building on ship tracking data from satellites Full text
2014
Mjelde, A. | Martinsen, K. | Eide, M. | Endresen, Ø
Arctic shipping is on the rise, leading to increased concern over the potential environmental impacts. To better understand the magnitude of influence to the Arctic environment, detailed modelling of emissions and environmental risks are essential. This paper describes a framework for environmental accounting. A cornerstone in the framework is the use of Automatic Identification System (AIS) ship tracking data from satellites. When merged with ship registers and other data sources, it enables unprecedented accuracy in modelling and geographical allocation of emissions and discharges. This paper presents results using two of the models in the framework; emissions of black carbon (BC) in the Arctic, which is of particular concern for climate change, and; bunker fuels and wet bulk carriage in the Arctic, of particular concern for oil spill to the environment. Using the framework, a detailed footprint from Arctic shipping with regards to operational emissions and potential discharges is established.
Show more [+] Less [-]Persistent organic pollutants in forage fish prey of rhinoceros auklets breeding in Puget Sound and the northern California Current Full text
2014
Good, Thomas P. | Pearson, Scott F. | Hodum, Peter | Boyd, Daryle | Anulacion, Bernadita F. | Ylitalo, Gina M.
Organochlorine contaminants in upper trophic-level consumers inhabiting Puget Sound are consistently higher than in those species inhabiting other west coast locations. We analyzed persistent organic pollutants (POPs) in the six most common fish prey of rhinoceros auklets breeding on Protection Island (Puget Sound), Tatoosh Island (WA coast), and Destruction Island (WA coast). Wet-weight concentrations of POPs ranged widely (PCBs: 1.6–25.0ng/g; DDTs: 0.2–56.0ng/g; PBDEs:<LOQ-49.0ng/g), but overall patterns showed fish from Puget Sound were 2–4 times more contaminated and had similar contaminant profiles compared to fish from the outer coast. Unexpectedly elevated PCB and PBDE concentrations in Chinook salmon from the outer coast likely reflected Columbia River. Calculating contaminant loads for auklet nestlings magnified differences observed between inland and outer coast fish prey. Monitoring of breeding auklets, their prey and other resident marine birds is needed to assess biomagnification impacts in the Puget Sound marine ecosystem.
Show more [+] Less [-]Intercomparison of tropospheric nitrogen dioxide retrieved from Ozone Monitoring Instrument over China Full text
2014
Zheng, Fengjie | Yu, Tao | Cheng, Tianhai | Gu, Xingfa | Guo, Hong
Tropospheric NO2 columns observed from the Ozone Monitoring Instrument (OMI) were evaluated and the seasonal characteristics were analyzed at eastern China with surface measurements. A comparison between the DP (DOMINO) and SP (Standard Product) tropospheric NO2 products from OMI different algorithms shows similar spatial and temporal variability, but DP is generally higher than SP by 13% in wintertime and lower 9% in summertime on average over East China. Larger differences occur on the significantly contaminated regions. The differences in seasonality are associated with emissions sources. In order to investigate and monitor the air pollution monitoring over east China, the relative contributions of the stratosphere–troposphere separation and air mass factors calculations to the observed difference between DP and SP tropospheric NO2 columns were compared. The seasonal difference due to stratosphere–troposphere separation is opposite in sign to the tropospheric vertical columns. Air mass factors (AMFs) of DP are smaller than SP AMFs, leading to higher DP tropospheric columns. Impacts induced by different AMFs calculation are crucial. Then, the differences of four cities in significant polluted areas were compared. The results showed apparent discrepancies between two products in local region with irregular monthly variation, however the seasonal mean columns demonstrated that basically DP is larger than SP. Overall, this study analyses the discrepancies in DP and SP, as well as the seasonal variations over East China which is an important implication for the control of nitrogen oxides.
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