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The role of citizen science in monitoring small-scale pollution events Texte intégral
2017
Hyder, Kieran | Wright, Serena | Kirby, Mark | Brant, Jan
Small-scale pollution events involve the release of potentially harmful substances into the marine environment. These events can affect all levels of the ecosystem, with damage to both fauna and flora. Numerous reporting structures are currently available to document spills, however there is a lack of information on small-scale events due to their magnitude and patchy distribution. To this end, volunteers may provide a useful tool in filling this data gap, especially for coastal environments with a high usage by members of the public. The potential for citizen scientists to record small-scale pollution events is explored using the UK as an example, with a focus on highlighting methods and issues associated with using this data source. An integrated monitoring system is proposed which combines citizen science and traditional reporting approaches.
Afficher plus [+] Moins [-]Spatial assessment of radiocaesium in the largest lagoon in Fukushima after the TEPCO Fukushima Dai-ichi Nuclear Power Station accident Texte intégral
2017
Kambayashi, Shota | Zhang, Jing | Narita, Hisashi
Radionuclides deposited on land by global fallouts and nuclear power station accidents spread over coastal environments through estuarine areas connecting land to ocean. In this study, we monitored activity concentration of radiocaesium in surface sediment and re-suspended particles in Matsukawa-ura lagoon, the largest lagoon in Fukushima, after the TEPCO Fukushima Dai-ichi Nuclear Power Station accident. Radiocaesium distribution in surface sediment varied spatiotemporally and irregularly due to the effect of tidal waves. The effective half-life was significantly shorter than physical half-life, suggesting some system of radiocaesium discharge in the lagoon. Sediment trap observation revealed re-suspended particles from sediment were transported to the ocean. For these reasons, it is suggested that re-suspension of particles in the lagoon and their transportation to the ocean by the seawater exchange process are important processes of radiocaesium discharge. Moreover, our results show that seawater exchange process contributes to the dispersion of radiocaesium in the ocean.
Afficher plus [+] Moins [-]Source apportionment of PM2.5 pollution in an industrial city in southern China Texte intégral
2017
Zou, Bei-Bing | Huang, Xiao Feng | Dai, Jing | Zhang, Bin | Zeng, Li-Wu | Feng, Ning | He, Ling-Yan
Severe PM2.5 pollution has become a great challenge to atmospheric pollution control in China. Most of previous aerosol source apportionment studies in China focused only on part of PM2.5 (e.g., organic matter in composition or PM1 in size) or lacked source contributions identified with necessary tempo-spatial variations, which makes the results not convincible enough for policy making. In this study, five various sites were selected for simultaneous PM2.5 observation in an industrial city in the Pearl River Delta (PRD) of South China during all four seasons of 2014. A positive matrix factorization (PMF) model was applied to the datasets of measured chemical species to perform source apportionment with the results as: (1) The annual mean PM2.5 concentration was 52.6 μg/m³, with secondary sulfate, vehicle emissions, secondary organic aerosol (SOA), and secondary nitrate identified as the major sources, contributing 24.6%, 14.5%, 12.0%, and 10.9% to PM2.5, respectively. Ship emissions, fugitive dust, biomass combustion, industrial emissions, and aged sea salt each contributed 3%–8%. (2) The tempo-spatial variations of sources reveal that secondary sulfate, SOA, biomass combustion, and ship emissions had obvious regional pollution characteristics; however, vehicle emissions, secondary nitrate, fugitive dust, and industrial emissions showed obvious local emission characteristics. (3) The exceeding standard polluted days (PM2.5>75 μg/m³) appeared with secondary nitrate, biomass burning, and SOA increasing mostly in concentration, which should be controlled more strictly. This study highlights the importance of SOA in PM2.5 pollution in China, which has been scarcely quantified for bulk PM2.5 in the literature.
Afficher plus [+] Moins [-]The impact of two oil spill events on the water quality along coastal area of Kenting National Park, southern Taiwan Texte intégral
2017
Chen, Chung-Chi | Tew, Kwee Siong | Ho, Ping-Ho | Ko, Fung-Chi | Hsieh, Hung-Yen | Meng, Pei-Jie
In 2009, the container ship Colombo Queen and the oil tanker W-O BUDMO grounded off Jialeshui and Houwan, respectively, in southern Taiwan. Water quality was monitored at each site to evaluate the environmental impact caused by the resulting oil spills. The results show that the PAHs, turbidity, and other nutrients increased shortly after oil spill, however levels of these parameters eventually returned to baseline levels. On the other hand, DO saturation, pH and chl. a decreased initially, reached maxima after 10days, and returned to the baseline levels after 14days. The chl. a concentration, pH and DO saturation fluctuated in a similar pattern at both sites during the oil spills, likely driven by algal blooms. In this study, we documented a full environmental recovery at coastal areas before, during and after the oil spills.
Afficher plus [+] Moins [-]Assessment of metal concentrations (Cu, Zn, and Pb) in seawater, sediment and biota samples in the coastal area of Eastern Black Sea, Turkey Texte intégral
2017
Baltas, Hasan | Sirin, Murat | Dalgic, Goktug | Bayrak, Esra Yilmaz | Akdeniz, Aysel
This study investigated the contents of Cu, Zn and Pb in seawater, sediment, different shell sizes of mussel (Mytilus galloprovincialis) and sea snail (Rapana venosa) samples collected from four different provinces of the Eastern Black Sea Region. With the exception of Zn, all the metal concentration values measured in the sea snail were observed to be higher than those of mussels in all stations. While the correlation between mussels and sea snail according to metal concentrations was found to be positive (p˂0.05), this relation was not observed between the other parameters, such as the shell sizes, salinity and pH (p˃0.05). Although the mean concentration values of Cu, Zn, and Pb for mussel and sea snail are significantly above the tolerable levels, the estimated daily intake values for mussel were below the daily intake recommended.
Afficher plus [+] Moins [-]Assessment of the benthic macrofauna in an artificial shell reef zone in Shuangdao Bay, Yellow Sea Texte intégral
2017
Liu, Guoshan | Li, Wen-Tao | Zhang, Xiumei
The effects of artificial shell reef (ASR) on the benthic macroinvertebrates were studied in Shuangdao Bay, Yellow Sea, China. Results showed that the biomass of macroinvertebrates in the ASR increased with the age of the ASR. Based on self-organizing map (SOM), the macroinvertebrate community of short-term artificial reef (SAR), medium-term artificial reef (MAR) and long-term artificial reef (LAR) emerged as a cluster, which may indicate that the benthic community in the ASR formed after three years. The age of the ASR was the main factor affecting the benthic community. The macroinvertebrates belonged to six phyla, Platyhelminthes, Nemertea, Annelida, Mollusca, Arthropoda and Echinodermata, among which the latter four were the ones that contributed the most for abundance. The biomass of Mollusca increased dramatically with age. The dissimilarity of the species composition of Mollusca was mainly caused by Meretrix meretrix and Protothaca jedoensis. The two species accounted for 15.61%, 28.05% and 75.11% of the macroinvertebrate biomass found in SAR, MAR and LAR, respectively. The ASR might be served as a bivalve stock enhancement tool. We conclude that ASR could assemble macrobenthos effectively and increase the environmental quality of the adjacent area, being a valid option for marine habitat restoration purposes.
Afficher plus [+] Moins [-]Polymer/reduced graphene oxide functionalized sponges as superabsorbents for oil removal and recovery Texte intégral
2017
Periasamy, Arun Prakash | Wu, Wen-Ping | Ravindranath, Rini | Roy, Prathik | Lin, Guan-Lin | Zhang, Huanzong
Polyurethane dish-washing (PU-DW) sponges are functionalized sequentially with polyethylenimine (PEI) and graphene oxide (GO) to form PEI/reduced graphene oxide (RGO) PU-DW sponges. The PEI/RGO PU-DW sponge consists of PEI/RGO sheets having numerous pores, with diameters ranging from 236 to 254nm. To further enhance hydrophobicity and absorption capacity of oil, PEI/RGO PU-DW sponge is further coated with 20% phenyltrimethoxysilane (PTMOS). The PTMOS/PEI/RGO PU-DW sponge absorbs various oils within 20s, with maximum absorption capacity values of 880% and 840% for bicycle chain oil and motorcycle engine oil, respectively. The absorbed oils were released completely by squeezing or immersed in hexane. The PTMOS/PEI/RGO PU-DW sponge efficiently separates oil/water mixtures through a flowing system. Having the advantages of faster absorption rate, reusability, and low cost, the PTMOS/PEI/RGO PU-DW sponge holds great potential as a superabsorbent for efficient removal and recovery of oil spills as well as for the separation of oil/water mixtures.
Afficher plus [+] Moins [-]Understanding how physical-biological coupling influences harmful algal blooms, low oxygen and fish kills in the Sea of Oman and the Western Arabian Sea Texte intégral
2017
Harrison, Paul J. | Piontkovski, Sergey | Al-Hashmi, Khalid
In the last decade, green Noctiluca scintillans with its symbiont and other dinoflagellates such as Cochlodinium polykrikoides, Prorocentrum micans and Scrippsiella trochoidea have become the dominant HABs, partially replacing the previously dominant diatoms and red Noctiluca scintillans, especially during the northeast monsoon. Fish kills in the Sea of Oman are linked to a slow seasonal decline in oxygen concentration from January to November, probably due to the decomposition of a series of algal blooms and the deep, low oxygen waters periodically impinging the Omani shelf. In the western Arabian Sea, cyclonic eddies upwell low oxygen, nutrient-rich water and the subsequent algal bloom decays and lowers the oxygen further and leads to fish kills. Warming of the surface waters by 1.2°C over the last 5 decades has increased stratification and resulted in a shoaling of the oxycline. This has increased the probability and frequency of upwelling low oxygen water and subsequent fish kills.
Afficher plus [+] Moins [-]Characteristics of two novel cold- and salt-tolerant ammonia-oxidizing bacteria from Liaohe Estuarine Wetland Texte intégral
2017
Huang, Xiao | Bai, Jie | Li, Kui-ran | Zhao, Yang-guo | Tian, Wei-jun | Dang, Jia-jia
To achieve a better contaminant removal efficiency in a low-temperature and high-salt environment, two novel strains of cold- and salt-tolerant ammonia-oxidizing bacteria (AOB), i.e., Ochrobactrum sp. (HXN-1) and Aquamicrobium sp. (HXN-2), were isolated from the surface sediment of Liaohe Estuarine Wetland (LEW), China. The optimization of initial ammonia nitrogen concentration, pH, carbon–nitrogen ratio, and petroleum hydrocarbons (PHCs) to improve the ammonia-oxidation capacity of the two bacterial strains was studied. Both bacterial strains showed a high ammonia nitrogen removal rate of over 80% under a high salinity of 10‰. Even at a temperature as low as 15°C, HXN-1 and HXN-2 could achieve an ammonia nitrogen removal rate of 53% and 62%, respectively. The cold- and salt-tolerant AOB in this study demonstrated a high potential for ammonia nitrogen removal from LEW.
Afficher plus [+] Moins [-]Assessment of marine debris on the coastal wetland of Martil in the North-East of Morocco Texte intégral
2017
Alshawafi, Adel | Analla, Mohamed | Alwashali, Ebrahim | Aksissou, Mustapha
Plastic waste at the coastal wetland in Martil beach in the North-East of Morocco is one of the problems that have appeared recently. This study aims to characterize the marine debris in the coast of Martil during the year 2015. The sampling is seasonally by type and size. The result shows, for the macro debris, the abundance of plastic (57%), lumber and paper (21.93%), cloth and fabric (7.8%), glass (5.42%), metal (4.40%), and rubber (3.4%). Micro debris is also present in the area in several forms such as wood, plants, and others by 75,63%. This was followed by the foam (26,95%), line (7,8%), and the film (1,23%). The seasonal variation (S1: January–March and S3: July to September) are the most polluted months of the year. The sources of marine debris are mainly tourism (beach users), land (run off), and commercial fishing in the four seasons of the year.
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