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A fish-based index for assessing the ecological status of Polish transitional and coastal waters
2015
Smoliński, Szymon | Całkiewicz, Joanna
Fish assemblages are considered indicators of aquatic ecosystem quality. Based on how fish communities respond to anthropogenic pressures, we developed a multimetric fish index for evaluating the health of both coastal and transitional waters. Fish data were collected along the Polish coast in the years 2011, 2013 and 2014 using different types of gear. Redundancy analysis showed that the most important environmental factor affecting fish community was salinity. Responses to anthropogenic disturbances of 20 candidate metrics were tested by generalized linear models, taking into account salinity, sampling protocol and the proxy of human pressures described by the Baltic Sea Impact Index (BSII). Five selected metrics were combined in a Multimetric Index, which showed negative significant correlation with BSII. The index presented herein appeared to be a good tool for assessing the ecological state of highly impacted Polish transitional and coastal areas and complies with the Water Framework Directive requirements.
اظهر المزيد [+] اقل [-]Combination of Unmix and PMF receptor model to apportion the potential sources and contributions of PAHs in wetland soils from Jiaozhou Bay, China
2015
Lang, Yin-Hai | Li, Guo Liang | Wang, Xiao-Mei | Peng, Peng
16 PAHs in Jiaozhou Bay wetland soils were analyzed by GC/MS. The potential sources and contributions were apportioned by Unmix and PMF models. The total concentrations of PAHs ranged from 176.1 to 563.3ng/g with a mean of 345.3ng/g. 2- and 3- rings PAHs were the dominant species accounting for 34.7–87.3% of the total PAHs. The similarities and differences of sources and contributions estimated by Unmix and PMF models were discussed. Three common sources (petrogenic source, coking oven and coal combustion) identified by two models, contributed 43.2%, 39.2% and 12.6% by Unmix and 33.5%, 29.1% and 16.0% by PMF to the total PAHs, respectively. In addition, diesel emission source (5.0%) by Unmix and a mixed source of diesel emission and natural gas burning (21.4%) by PMF were also extracted. It is essential to apply multiple source apportionment techniques to estimate potential source and contributions in further study.
اظهر المزيد [+] اقل [-]Effect of orthophosphate and bioavailability of dissolved organic phosphorous compounds to typically harmful cyanobacterium Microcystis aeruginosa
2015
Li, Jihua | Wang, Zhongwei | Cao, Xin | Wang, Zhengfang | Zheng, Zheng
Results show that Microcystis aeruginosa can utilize both dissolved organic phosphorus (DOP) and orthophosphate (DIP) even under low phosphorus (P) conditions to sustain its growth. Total P concentrations decreased markedly in all three P source treatments. Alkaline phosphatase activity (APA) in the different P sources tested changed in response to the DOP and DIP. The APA of DOP groups remained low after decreasing significantly, but the APA in the DIP treatments remained high during the period of culture. Changes in APA at different PO43−–P concentrations in a culture medium revealed negative correlations between APA and DIP. However, a positive relationship was observed between APA and DOP under low P concentrations. These findings indicate that M. aeruginosa can regulate its physiological metabolism to acclimate to low ambient DIP environments.
اظهر المزيد [+] اقل [-]Heavy metals and TPH effects on microbial abundance and diversity in two estuarine areas of the southern-central coast of São Paulo State, Brazil
2015
Pinto, Aline Bartelochi | Pagnocca, Fernando Carlos | Pinheiro, Marcelo Antonio Amaro | Fontes, Roberto Fioravanti Carelli | Oliveira, Ana Júlia Fernandes Cardoso de
Coastal areas may be impacted by human and industrial activities, including contamination by wastewater, heavy metals and hydrocarbons. This study aimed to evaluate the impact of hydrocarbons (TPH) and metals on the microbiota composition and abundance in two estuarine systems in the coast of São Paulo: the Santos (SE) and Itanhaém (IE) estuaries. The SE was found to be chronically contaminated by heavy metals and highly contaminated by hydrocarbons. This finding was correlated with the increased density of cyanobacteria in sediments and suggests the possible use of cyanobacteria for bioremediation. These contaminants influence the density and composition of estuarine microbiota that respond to stress caused by human activity. The results are troubling because quantitative and qualitative changes in the microbiota of estuarine sediments may alter microbiological processes such as decomposition of organic matter. Moreover, this pollution can result in damage to the environment, biota and human health.
اظهر المزيد [+] اقل [-]Heavy metals in surface sediments of the intertidal Laizhou Bay, Bohai Sea, China: Distributions, sources and contamination assessment
2015
Zhang, Jinfeng | Gao, Xuelu
Surface sediments from the intertidal zone of the southwestern Laizhou Bay were analyzed for heavy metals to seek their concentrations, distributions, pollution status, potential ecological risks and possible sources. The concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn were in the ranges of 4.65–9.65, 0.11–0.28, 25.85–42.75, 7.57–21.29, 0.022–0.054, 12.85–25.35, 9.65–17.65 and 38.22–73.81μgg−1 dry sediment weight, respectively. Cd and Hg presented a status of no pollution to moderate pollution and moderate to considerable potential ecological risks; they were enriched to some extent at some sampling stations, while the other studied metals were not. The combined effects of the studied metals in the sediments made them have a 21% probability of being toxic to biota. The results indicated that As, Cr, Cu, Zn, Ni and Pb were mainly from natural contribution, while a significant portion of Cd and Hg was likely from anthropogenic discharges in addition to natural inputs.
اظهر المزيد [+] اقل [-]Novel flame retardants (N-FRs), polybrominated diphenyl ethers (PBDEs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in fish, penguin, and skua from King George Island, Antarctica
2015
Wolschke, Hendrik | Meng, Xiang-Zhou | Xie, Zhiyong | Ebinghaus, Ralf | Cai, Minghong
Persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), are frequently detected in biota from Antarctica, whereas no data are available for their replacements, such as novel flame retardants (N-FRs). This study presented the occurrence of several N-FRs, PBDEs, and PCBs in tissue samples of an Antarctic rock cod (Trematomus bernacchii), a young gentoo penguin (Pygoscelis papua), and a brown skua (Stercorarius antarcticus) collected from King George Island. The total concentrations of N-FRs (ΣN-FRs; mean: 931pg/g dry weight (dw)) were comparable to PBDEs (Σ8PBDEs; 681pg/gdw), which were much lower than PCBs (ΣDL-PCBs; 12,800pg/gdw). Overall, skua contained two to three orders of magnitude higher contamination than penguin and fish. In the future, more attention should be focused on the fate of N-FRs in Antarctica, where usages have increased since PBDEs were banned. To our knowledge, this is the first report of N-FRs in biota from Antarctica.
اظهر المزيد [+] اقل [-]Particulate matter in ambient air and its association with alterations in lung functions and respiratory health problems among outdoor exercisers in National Capital Region, India
2015
Kesavachandran, Chandrasekharan Nair | Kamal, Ritul | Bihari, Vipin | Pathak, Manoj Kumar | Singh, Amarnath
Regular exercise improves physiological processes and yields positive health outcomes. However, it is relatively less known that exposure to air pollution during outdoor exercises may actually exacerbate several health problems. The present cross–sectional study was undertaken to assess the particulate matter (PM) in the ambient air and its association with lung functions, pulse rate and respiratory problems among 378 outdoor exercisers in the National Capital Region (NCR), India. Lung functions were measured using a Spirometer (PIKO–1, PIKO–6) and respiratory problems were recorded through a questionnaire–based survey. Concentrations of particulate matter smaller than 2.5 and 1 microns were monitored at 10 locations across the study area using an online automated ambient air monitoring instrument–HAZ–DUST (EPAM–5000). Decline in Forced Expiratory Volume in 1 sec–FEV1 (p<0.001) and Peak Expiratory Flow Rate–PEFR (p<0.001) was observed among the outdoor exercisers compared to the Indian reference values. Ambient air monitoring showed higher PM2.5 concentrations at all the study locations compared to the recommended permissible levels for residential areas in India. Risk of FEV1 (%) predicted cases with <80% showed an increase from 2.32% to 8.69% among the exercisers with respect to PM1 concentration from lower to higher limit at the study locations. Similarly, PEFR showed an increased risk of predicted cases <80% from 0.78% to 2.91% among outside exercisers for lower to higher limit of PM1 concentration. Cases with FEV1 predicted <80% increased from 2.56% to 13.98% and for PEFR from 0.96% to 5.24% among outdoor exercisers for the corresponding lower to higher limits of PM2.5 concentrations. The study demonstrates that outdoor exercisers in locations with high PM concentrations are at a risk of lung function impairment. These impairments are due to deposition of PM in the smaller and larger airways.
اظهر المزيد [+] اقل [-]Spatial variability of three benthic indices for marine quality assessment in a subtropical estuary of Southern Brazil
2015
Brauko, Kalina Manabe | Souza, Fernanda Maria de | Muniz, Pablo | Camargo, Maurício Garcia de | Lana, Paulo da Cunha
Indices based on macrobenthic responses to disturbance remain to be adequately tested for the detection of spatial variability by robust sampling designs. We present herein a congruence test to real-world data of the widely used indices AMBI, M-AMBI and BENTIX in tidal flats of a subtropical estuary. We used a hierarchical sampling design to evaluate the spatial variability of the indices in response to distinct levels of sewage contamination. Indices were then tested for correlations with chemical proxies of contamination and for the similarity of responses. BENTIX and M-AMBI produced over- and underestimations of ecological status. We found a low degree of similarity among indices as an expression of the spatial variation of macrofaunal assemblages on their performances. Only AMBI varied at the contamination scale (103m) and was congruent with physical–chemical proxies. Ambiguous responses indicated effects of natural inputs of organic matter rather than environmental quality associated to sewage.
اظهر المزيد [+] اقل [-]Analysis of a decade of Asian outflow of PM10 and TSP to Gosan, Korea; also incorporating Radon–222
2015
Crawford, Jagoda | Chambers, Scott | Kang, Ch'ang-hŭi | Griffiths, Alan | Kim, Won-Hyung
Ten years of aerosol and Radon–222 (radon) data from Gosan, Korea, were analyzed. Seasonal cycles were strongly linked to changes in fetch and time of year. We estimated that 7.21t/m y of PMio aerosol pass Gosan in the atmospheric boundary layer, increasing annually by 0.3t/m y. Contributions to aerosol loading were characterized by fetch: South China, North China, Korea and Japan. While the highest, and most variable, contributions typically originated from South China, these air masses contributed to only 6% of the overall dataset. PM10 distributions were broader from South and North China than for Korea or Japan, reflecting differences in natural/anthropogenic soil sources, and number/distribution of large point sources. Employing radon to select air masses more representative of targeted fetch regions typically resulted in greater reported pollutant concentrations and rates of change over the decade. Estimated rates of PM10 increase from North China and Korea over the decade were 1.4 and 0.9μg/m3 y, respectively. Total suspended particulate (TSP) elemental analysis indicated that the (non–sea–salt) nss–SO42− content of aerosols has been gradually increasing over the past decade and more recently an increase in NO3− was seen. However, on average, rates of increase in nss–SO42− have reduced since 2007, which were higher in South than North China.
اظهر المزيد [+] اقل [-]Dynamite fishing in Tanzania
2015
Slade, Lorna M. | Kalangahe, Baraka
Fishing using explosives is common in Tanzanian waters; it is considered to be more widely practised now than at any other point in history. Mwambao Coastal Community Network, a Tanzanian NGO carried out a multi-stakeholder consultation in April 2014 initiated through the concern of private investors and tourism operators. Consultations were held with villagers, fisheries officers, government officers, hoteliers, dive operators, fish processors, NGOs and other key individuals, and shed some light on key factors enabling this practice to flourish. Key areas identified for attention include engendering political will at all levels, upholding of the law through a non-corrupt enforcement and judicial system, and defining clear roles and responsibilities for monitoring and surveillance. The work identified other successful initiatives which have tackled this pervasive practice including projects that build local capacity for marine governance, villages that have declared themselves intolerant of blast-fishing, and private–public partnerships for patrol and protection.
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