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Loss of native rocky reef biodiversity in Australian metropolitan embayments Полный текст
2015
Stuart-Smith, Rick D. | Edgar, Graham J. | Stuart-Smith, Jemina F. | Barrett, Neville S. | Fowles, Amelia E. | Hill, Nicole A. | Cooper, Antonia T. | Myers, Andrew P. | Oh, Elizabeth S. | Pocklington, Jacqui B. | Thomson, Russell J.
Urbanisation of the coastal zone represents a key threat to marine biodiversity, including rocky reef communities which often possess disproportionate ecological, recreational and commercial importance. The nature and magnitude of local urban impacts on reef biodiversity near three Australian capital cities were quantified using visual census methods. The most impacted reefs in urbanised embayments were consistently characterised by smaller, faster growing species, reduced fish biomass and richness, and reduced mobile invertebrate abundance and richness. Reef faunal distribution varied significantly with heavy metals, local population density, and proximity to city ports, while native fish and invertebrate communities were most depauperate in locations where invasive species were abundant. Our study adds impetus for improved urban planning and pollution management practises, while also highlighting the potential for skilled volunteers to improve the tracking of changes in marine biodiversity values and the effectiveness of management intervention.
Показать больше [+] Меньше [-]Historical trends (1998–2012) of nickel (Ni), copper (Cu) and chromium (Cr) concentrations in marine sediments at four locations in the Northern Adriatic Sea Полный текст
2015
Traven, Luka | Furlan, Nikolina | Cenov, Arijana
Historical trends (1998–2012) nickel (Ni), copper (Cu) and chromium (Cr) concentrations in marine sediments were assessed at four locations in the Northern Adriatic Sea (Croatia) in the proximity of an oil refinery. Ecological risks were characterized by benchmarking the dataset against Sediment Quality Guidelines (SQG). A significant number of samples had Ni values above ERL with no exceedance of the ERL values for Cu and Cr. Weak positive historical trends were found for only for Cu. At all sites there were statistically significant correlations between Ni and Cr indicating a common origin of these heavy metals in the investigated marine sediments. There were statistically significant differences between the sites under the direct influence of the oil refinery compared to the control site indicating the possibility that the oil refinery is contributing to the concentration of these heavy metals in the marine sediments.
Показать больше [+] Меньше [-]Intrinsic bioremediation potential of a chronically polluted marine coastal area Полный текст
2015
Catania, Valentina | Santisi, Santina | Signa, Geraldina | Vizzini, Salvatrice | Mazzola, Antonio | Cappello, Simone | Yakimov, Michail M. | Quatrini, Paola
A microbiological survey of the Priolo Bay (eastern coast of Sicily, Ionian Sea), a chronically polluted marine coastal area, was carried out in order to discern its intrinsic bioremediation potential. Microbiological analysis, 16S rDNA-based DGGE fingerprinting and PLFAs analysis were performed on seawater and sediment samples from six stations on two transects. Higher diversity and variability among stations was detected by DGGE in sediment than in water samples although seawater revealed higher diversity of culturable hydrocarbon-degrading bacteria. The most polluted sediment hosted higher total bacterial diversity and higher abundance and diversity of culturable HC degraders. Alkane- and PAH-degrading bacteria were isolated from all stations and assigned to Alcanivorax, Marinobacter, Thalassospira, Alteromonas and Oleibacter (first isolation from the Mediterranean area). High total microbial diversity associated to a large selection of HC degraders is believed to contribute to natural attenuation of the area, provided that new contaminant contributions are avoided.
Показать больше [+] Меньше [-]Marine litter in bottom trawls off the Portuguese coast Полный текст
2015
Neves, Diogo | Sobral, Paula | Pereira, Tânia
Benthic marine litter along the Portuguese coast, was recorded in 14 trips on stern trawlers covering a distance of 2117km and an area of 56.2km2, average depth range 90–349m. 2034 items of marine litter were registered, 76% were plastics and 38.6% were originated from fishing related activities. Plastic was present in all the trawls and had the highest average density of all litter categories, 50itemskm−2.The highest density of marine litter (178.9±64.0itemskm−2) was found in the proximity of the Tagus river mouth, probably related to the high population density in the Lisbon metropolitan area.This study highlights the need to raise fishermen awareness for the adoption of good environmental practices that will contribute to the reduction of marine litter.
Показать больше [+] Меньше [-]Comparisons of GM (1,1), and BPNN for predicting hourly particulate matter in Dali area of Taichung City, Taiwan Полный текст
2015
Chen, Li | Pai, Tzu-Yi
This paper represents the first study to compare seven types of first–order and one–variable grey differential equation model [abbreviated as GM (1, 1)] and back-propagation artificial neural network (BPNN) for predicting hourly particulate matter (PM) including PMio and PM2.5 concentrations in Dali area of Taichung City, Taiwan. Their prediction performance was also compared. The results indicated that the minimum mean absolute percentage error (MAPE), mean squared error (MSE), and root mean squared error (RMSE) was 16.76%, 132.95, and 11.53, respectively for PM10 prediction. For PM2.5 prediction, the minimum MAPE, MSE, and RMSE value of 21.64%, 40.41, and 6.36, respectively could be achieved. All statistical values revealed that the predicting performance of GM (1, 1, x(0)), GM (1, 1, a), and GM (1, 1, b) outperformed other GM (1, 1) models. According to the results, it revealed that GM (1, 1) could predict the hourly PM variation precisely even comparing with BPNN.
Показать больше [+] Меньше [-]Investigation of polycyclic aromatic hydrocarbons (PAHs) and cyclic terpenoid biomarkers in the sediments of fishing harbors in Taiwan Полный текст
2015
Kao, Nien-Hsin | Su, Ming-Chien | Fan, Jheng-Rong | Yen, Chih-Chun
Three fishing harbors were investigated to study the polycyclic aromatic hydrocarbons in the sediments and trace possible anthropogenic sources by identification of cyclic terpenoid biomarkers. Seventeen terpanes, 10 steranes and 10 bicyclic sesquiterpanes in the marine diesel and the three kinds of lubricants that are mainly used by fishing boats were identified and quantified. Eighteen biomarker diagnostic ratios are suggested and the correlation coefficients among the lubricants and sediment samples have the R2 value greater than 0.73. Analyzed 16 PAHs in the sediment shows non-normal distributions and the Kruskal Wallis Test shows the significant differences (p value smaller than 0.05) with the greatest variability in benzo[g,h,i]perylene which more than 84% of the effective size (E.S.) is accounted. X-ray Photoelectron Spectroscopy (XPS) analysis was applied and the Kruskal Wallis Test shows a significant difference (p value smaller than 0.05) among certain atoms with the effective size greater than 60%.
Показать больше [+] Меньше [-]Geochemical and isotopic data for restricting seawater intrusion and groundwater circulation in a series of typical volcanic islands in the South China Sea Полный текст
2015
Zhang, Wenjie | Chen, Xi | Tan, Hongbing | Zhang, Yanfei | Cao, Jifu
The decline of groundwater table and deterioration of water quality related to seawater have long been regarded as a crucial problem in coastal regions. In this work, a hydrogeologic investigation using combined hydrochemical and isotopic approaches was conducted in the coastal region of the South China Sea near the Leizhou peninsular to provide primary insight into seawater intrusion and groundwater circulation. Hydrochemical and isotopic data show that local groundwater is subjected to anthropogenic activities and geochemical processes, such as evaporation, water–rock interaction, and ion exchange. However, seawater intrusion driven by the over-exploitation of groundwater and insufficient recharge is the predominant factor controlling groundwater salinization. Systematic and homologic isotopic characteristics of most samples suggest that groundwater in volcanic area is locally recharged and likely caused by modern precipitation. However, very depleted stable isotopes and extremely low tritium of groundwater in some isolated aquifers imply a dominant role of palaeowater.
Показать больше [+] Меньше [-]A preliminary assessment of polychlorinated biphenyls and polybrominated diphenyl ethers in deep-sea sediments from the Indian Ocean Полный текст
2015
Cheng, Zhineng | Lin, Tian | Xu, Weihai | Xu, Yue | Li, Jun | Luo, Chunling | Zhang, Gan
Ten surface sediments were collected from the open Indian Ocean at depths below 4000m in 2011, for the analysis of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). The concentrations of Σ32 PCBs, Σ7 PBDEs, and BDE-209 were 120–514, 49–152, and 7–133pg/g, respectively. These concentrations are close to the lowest values recorded in the global marine environment. The PCBs had a relatively uniform composition, and were dominated by low chlorinated congeners. The concentrations of di-, tri-, and tetra-PCBs were strongly correlated with the total organic carbon (TOC), suggesting the dissolved PCBs were derived from the atmosphere via diffusive air–water exchange, and absorbed by phytoplankton. A high proportion of BDE209 was only detected in the sediment of the low fan of the Ganga River. There were weak correlations between low brominated BDEs and TOC, implying the degradation of BDE209 is a possible source of lower-brominated BDEs in deep-sea sediments.
Показать больше [+] Меньше [-]Surface sediment properties and heavy metal pollution assessment in the near-shore area, north Shandong Peninsula Полный текст
2015
Xu, Gang | Pei, Shaofeng | Liu, Jian | Gao, Maosheng | Hu, Gang | Kong, Xianghuai
Samples of surface sediment were collected off the north Shandong Peninsula for grain size and element analyses. Based on the grain size analysis, the surface sediments were dominated by silt and sand, with a small portion of clay, and were probably from the coastal erosion of the Shandong Peninsula. The spatial distribution patterns of the heavy metals were primarily controlled by the sediment types. The geo-accumulation indexes suggest that there was no Cu, Zn and Cr pollution in the study area; Pb and Cd contaminations appeared only at a few stations, while As pollution was distributed widely. The enrichment factors indicated that Cu, Zn and Cr were primarily from terrigenous materials. By contrast, Cd, Pb and As, and especially Cd and As, were probably largely provided by anthropogenic sources. Due to the dilution of coarse-grained matters, there was no contamination at some of the stations at which the influence of human activities was obvious.
Показать больше [+] Меньше [-]Impact of cigarette butt leachate on tidepool snails Полный текст
2015
Booth, David J. | Gribben, Paul | Parkinson, Kerryn
In urban areas, cigarette butts are the most common discarded refuse articles. In marine intertidal zones, they often fall into tidepools. We tested how common intertidal molluscs were affected by butt leachate in a laboratory experiment, where snails were exposed to various leachate concentrations. Mortality was very high, with all species showing 100% mortality at the full leachate concentration (5 butts per litre and 2h soak time) after 8days. However, Austrocochlea porcata showed higher mortality than the other 2 species at lower concentrations (10%, 25%) which may affect the relative abundance of the 3 snails under different concentrations of leachate pollution. Also, sublethal effects of leachate on snail activity were observed, with greater activity of Nerita atramentosa than the other 2 species at higher concentrations, suggesting it is more resilient than the other 2 species.While human health concerns predominate with respect to smoking, we show strong lethal and sublethal (via behavioural modifications) impacts of discarded butts on intertidal organisms, with even closely-related taxa responding differently.
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