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Factor associated variations in the home range of a resident Adriatic common bottlenose dolphin population
2017
Rako-Gospić, Nikolina | Radulović, Marko | Vučur, Tihana | Pleslić, Grgur | Holcer, Draško | Mackelworth, Peter
This study investigates the influence of the most dominant factors (association patterns, gender, natal philopatry and anthropogenic pressure) on the home range size of the 44 most resident common bottlenose dolphins (Tursiops truncatus) inhabiting the waters of the Cres-Lošinj archipelago (north Adriatic Sea, Croatia), a recently declared NATURA 2000 SCI. Results show that variations in home range patterns (MCP, 95% KDE and 50% KDE home range size) among the individual resident dolphins are primarily related to differences in gender and reflect the way in which different genders respond to external stressors. In addition, results confirm the seasonal influence of nautical tourism on both female and male dolphins through changes in their home range sizes. The overall results improve current knowledge of the main anthropogenic threats that should be taken into consideration when developing conservation measures to be applied to this Cres and Lošinj SCI.
Afficher plus [+] Moins [-]The impact of wastewater treatment effluent on microbial biomasses and diversities in coastal sediment microcosms of Hangzhou Bay
2017
Tao, Yile | Dai, Tianjiao | Huang, Bei | Wen, Donghui
Disposal of wastewater treatment plant (WWTP) effluent into sea, a typical anthropogenic disturbance, may influence many environmental factors and change the coastal microbial community structure. In this study, by setting up coastal sediment microcosms perturbed by WWTP effluent, the changes of microbial community structure under different degree of disturbances were investigated. Quantitative PCR (qPCR) and terminal restriction fragment length polymorphism (T-RFLP) were used to analyzed the biomass and biodiversity. High throughput sequencing analysis was used to identify the classification of the microorganisms. Our study suggested that low ratio of WWTP effluent may stimulate dominant species, which increase the biomass but decrease the biodiversity; while high ratio of WWTP effluent may depress all species, which decrease the biomass but increase the biodiversity. In other words, the impact was dose-dependent. The changes of microbial community structure may provide a metric for water environmental assessment and pollution control.
Afficher plus [+] Moins [-]Impact of habitat management on waterbirds in a degraded coastal wetland
2017
Wei, Pingping | Zan, Qijie | Tam, Nora F.Y. | Shin, Paul K.S. | Cheung, S.G. | Li, Mingguang
The loss of coastal wetlands in Hong Kong Mai Po Nature Reserve adversely affected wetland-depended species. To mitigate this impact, gei wai ponds were reconstructed according to a set of biodiversity management zones (BMZs). This study, based on Canonical Correspondence Analysis (CCA), investigated if waterbird distribution was related to BMZ characteristics. Based on habitat characteristics, ponds in the same BMZ generally clumped in the same quadrant or within a short distance on CCA scatter plots, indicating that a BMZ zone produced common habitat traits. Ponds in a close distance on the plot had similar bird abundance or community structure. Significant correlations were noted between the abundance of cormorants and tall tree, and between waders and bare ground areas within study ponds. This study indicated that the control of key habitat factors was important for the success of reconstruction of gei wais and management of waterbirds in Mai Po.
Afficher plus [+] Moins [-]Comparing different methods for fast screening of microbiological quality of beach sand aimed at rapid-response remediation
2017
Testolin, Renan C. | Almeida, Tito C.M. | Polette, Marcus | Branco, Joaquim O. | Fischer, Larissa L. | Niero, Guilherme | Poyer-Radetski, Gabriel | Silva, Valéria C. | Somensi, Cleder A. | Corrêa, Albertina X.R. | Corrêa, Rogério | Rörig, Leonardo R. | Itokazu, Ana Gabriela | Férard, Jean-François | Cotelle, Sylvie | Radetski, Claudemir M.
There is scientific evidence that beach sands are a significant contributor to the pathogen load to which visitors are exposed. To develop beach quality guidelines all beach zones must be included in microbiological evaluations, but monitoring methods for beach sand quality are relatively longstanding, expensive, laborious and require moderate laboratory infrastructure. This paper aimed to evaluate the microorganism activity in different beach zones applying and comparing a classical method of membrane filtration (MF) with two colorimetric screening methods based on fluorescein (FDA) and tetrazolium (TTC) salt biotransformation to evaluate a new rapid and low-cost method for beach sand microbiological contamination assessments. The colorimetric results can help beach managers to evaluate rapidly and at low cost the microbiological quality of different beach zones in order to decide whether remedial actions need to be adopted to prevent exposure of the public to microbes due to beach sand and/or water contamination.
Afficher plus [+] Moins [-]Comparative efficacy of benthic biotic indices in assessing the Ecological Quality Status (EcoQS) of the stressed Ulhas estuary, India
2017
Mulik, Jyoti | Sukumaran, Soniya | Srinivas, Tatiparthi | Vijapure, Tejal
Ecostatus of Ulhas estuary, one of the most polluted estuaries along the industrialized and urbanized northwest coast of India, was evaluated by six widely accepted benthic indices viz. H′(log2), AMBI, M-AMBI, BENTIX, BOPA and BO2A to test their efficiency in a tropical setting. The mesohaline zone, which presented eutrophic conditions, was classified as ‘bad’ by all indices due to the azoic status. Despite significant correlations obtained between indices, there were discrepancies in the accurate level of EcoQS assigned to each station. AMBI was observed to be most efficient in indicating a clear spatial variability from a ‘poor’ to ‘bad’ ecological quality status in the middle and upstream zones to an improved status in the downstream region. Limitations of all indices are discussed in light of their suitability for assessing the estuarine environmental condition. The present results could provide a fillip to environmental improvement initiatives currently being undertaken in the estuary.
Afficher plus [+] Moins [-]Distribution and enrichment of trace metals in surface marine sediments in the Gulf of Pozzuoli and off the coast of the brownfield metallurgical site of Ilva of Bagnoli (Campania, Italy)
2017
Trifuoggi, Marco | Donadio, Carlo | Mangoni, Olga | Ferrara, Luciano | Bolinesi, Francesco | Nastro, Rosa Anna | Stanislao, Corrado | Toscanesi, Maria | Di Natale, Gabriella | Arienzo, Michele
The distribution of metals in surface sediments of Gulf of Pozzuoli (GoP), embedding the former second Italian largest integrated steelworks of Bagnoli, was studied based on sediment dispersal, quality guidelines (SQGs) and quantitative pollution indices of the respective metals. As, Cd, Hg, Pb, Zn largely exceeded the limits. Hg had a mean of 5.8mg/kg, twentyfold higher the rule, accumulating primarily near Bagnoli site. The mean effective range quotient, m-ERM-Q, revealed a high potential for negative biological effects especially in the area nearby the Bagnoli site. The enrichment factor (EF) values were outstandingly high, >1.5 with values which were often ≥100. The geoaccumulation index, Igeo, was very critical for Cr, Cu, Hg and Ni, showing an Igeo in the range of strongly polluted (4<Igeo <5) and very strongly polluted (Igeo>5). The principal component analysis (PCA) and Pearson's correlation matrix (CM), excluded significant contribution from weathering products.
Afficher plus [+] Moins [-]Chemoreception drives plastic consumption in a hard coral
2017
Allen, Austin S. | Seymour, Alexander C. | Rittschof, Daniel
The drivers behind microplastic (up to 5mm in diameter) consumption by animals are uncertain and impacts on foundational species are poorly understood. We investigated consumption of weathered, unfouled, biofouled, pre-production and microbe-free National Institute of Standards plastic by a scleractinian coral that relies on chemosensory cues for feeding. Experiment one found that corals ingested many plastic types while mostly ignoring organic-free sand, suggesting that plastic contains phagostimulents. Experiment two found that corals ingested more plastic that wasn't covered in a microbial biofilm than plastics that were biofilmed. Additionally, corals retained ~8% of ingested plastic for 24h or more and retained particles appeared stuck in corals, with consequences for energetics, pollutant toxicity and trophic transfer. The potential for chemoreception to drive plastic consumption in marine taxa has implications for conservation.
Afficher plus [+] Moins [-]Assessment of microplastic-sorbed contaminant bioavailability through analysis of biomarker gene expression in larval zebrafish
2017
Sleight, Victoria A. | Bakir, Adil | Thompson, Richard C. | Henry, Theodore B.
Microplastics (MPs) are prevalent in marine ecosystems. Because toxicants (termed here “co-contaminants”) can sorb to MPs, there is potential for MPs to alter co-contaminant bioavailability. Our objective was to demonstrate sorption of two co-contaminants with different physicochemistries [phenanthrene (Phe), log10Kow=4.57; and 17α-ethinylestradiol (EE2), log10Kow=3.67] to MPs; and assess whether co-contaminant bioavailability was increased after MP settlement. Bioavailability was indicated by gene expression in larval zebrafish. Both Phe and EE2 sorbed to MPs, which reduced bioavailability by a maximum of 33% and 48% respectively. Sorption occurred, but was not consistent with predictions based on co-contaminant physicochemistry (Phe having higher log10Kow was expected to have higher sorption). Contaminated MPs settled to the bottom of the exposures did not lead to increased bioavailability of Phe or EE2. Phe was 48% more bioavailable than predicted by a linear sorption model, organism-based measurements therefore contribute unique insight into MP co-contaminant bioavailability.
Afficher plus [+] Moins [-]Plankton resting stages in recent sediments of Haifa port, Israel (Eastern Mediterranean) - Distribution, viability and potential environmental consequences
2017
Rubino, Fernando | Belmonte, Manuela | Galil, Bella S.
Resting stages of plankton were sampled in the surficial sediments in the port of Haifa, Israel, on the eve of a major port enlargement project. We recorded the structure of the assemblages and examined their relationship with different environments within the port. Our findings reveal a remarkably high diversity coupled with low density and the highest number of oligotrich ciliate cyst types recorded from marine sediments. Near the eutrophic and highly polluted zone of the Kishon estuary ciliates were more abundant than elsewhere in the port, whereas dinoflagellates' abundance was reduced, and these trends held true both for full and empty cysts. Some harmful or potentially toxic species, such as Scrippsiella acuminata, were widespread in the port. The toxigenic species include Alexandrium minutum, Gymnodinium uncatenatum and Lingulodinium polyedrum. Active cells of the unarmoured, bloom-forming Akashiwo sanguinea were identified in the cultures obtained from the incubated sediments.
Afficher plus [+] Moins [-]Using seagrasses to identify local and large-scale trends of metals in the Mediterranean Sea
2017
Roca, Guillem | Romero, Javier | Farina, Simone | Martínez-Crego, Begoña | Alcoverro, Teresa
To manage trace metal pollution it is critical to determine how much temporal trends can be attributed to local or large-scale sources. We tracked changes in metal content in the seagrass Posidonia oceanica, along the NW Mediterranean from 2003 to 2010. While Cu, Cd and Ni showed a large inter-site variation, likely due to local factors, Fe, Mn and Pb showed little local variation and synchronous interannual variability across sites, most likely due to large-scale sources. Zn showed equal importance of local and large-scale sources of variation. Temporal trends of Ni, Zn, Cd, Cu remained almost stable. In contrast, Fe, Mn and Pb slightly increased in the last decade. These trends suggest that metals like Cu, Cd, Ni can be effectively managed at local scale. Whereas, elements like Fe, Mn and Pb have an important large-scale component that needs to be managed across the frontiers of national jurisdictions.
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