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Linking fish species traits to environmental conditions in the Jakarta Bay-Pulau Seribu coral reef system
2017
Cleary, Daniel F.R.
Coral reefs around the globe have been subjected to a wide range of stressors. In the present study, fish species were recorded across a pronounced in-to-offshore gradient in the Jakarta Bay-Pulau Seribu reef system. In addition to this, fish species traits were obtained from FishBase. RLQ analysis revealed a significant association between fish species traits and environmental variables. Fish species associated with perturbed, inshore waters were resilient to disturbance, had higher mortality rates, higher growth rates and mainly consumed animals. In contrast, fish species associated with less perturbed, mid- and offshore waters had greater life expectancy, higher age at maturity, greater life span, greater generation time and mainly fed on plants or plants and animals. Eutrophication, pollution and physical destruction of coral substrate in inshore waters has thus selected for a low biomass and depauperate fish community characterised by fast growing and short lived species.
Afficher plus [+] Moins [-]Concentrations of metallic elements in kidney, liver, and lung tissue of Indo-Pacific bottlenose dolphin Tursiops aduncus from coastal waters of Zanzibar, Tanzania
2017
Mapunda, Edgar C. | Othman, Othman C. | Akwilapo, Leonard D. | Bouwman, Hindrik | Mwevura, Haji
Concentrations of metallic elements in kidney, liver and lung tissues of Indo-Pacific bottlenose dolphins Tursiops aduncus from coastal waters of Zanzibar were determined using inductively coupled plasma – optical emission spectroscopy. Cadmium, chromium, copper, and zinc were quantifiable in all tissues at concentration ranges of 0.10–150, 0.08–3.2, 1.1–88 and 14–210μg/g dry mass, respectively. Copper and zinc was significantly higher in liver, and females had significantly higher Cd in liver, and chromium in lung. Generally, T. aduncus dolphins from coastal waters around Zanzibar carry low concentrations of metals compared with dolphins from other areas. Cadmium increased significantly with age in kidney and lung. Copper decreased significantly with age in liver, probably due to foetal metallothionein. This study supplied baseline data against which future trends in marine mammals in the Indian Ocean, the world's third largest, can be assessed.
Afficher plus [+] Moins [-]Natural and anthropogenic events influence the soundscapes of four bays on Hawaii Island
2017
Heenehan, Heather L. | Van Parijs, Sofie M. | Bejder, Lars | Tyne, Julian A. | Southall, Brandon L. | Southall, Hugh | Johnston, David W.
The soundscapes of four bays along the Kona Coast of Hawaii Island were monitored between January 2011 and March 2013. Equivalent, unweighted sound pressure levels within standard 1/3rd-octave bands (dB re: 1μPa) were calculated for each recording. Sound levels increased at night and were lowest during the daytime when spinner dolphins use the bays to rest. A tsunami provided an opportunity to monitor the soundscape with little anthropogenic component. We detected a decrease in sound levels and variability in one of the busiest bays. During the daytime in the 3.15kHz 1/3rd octave band, we detected 92 loud outliers from vessels, aquaculture, and military mid-frequency active sonar. During one military mid-frequency active sonar event sound levels reached 45.8dB above median ambient noise levels. The differences found in the bays illustrate the importance of understanding soundscapes to effectively manage noise pollution in marine ecosystems.
Afficher plus [+] Moins [-]Enrichment, isolation, and biodegradation potential of long-branched chain alkylphenol degrading non-ligninolytic fungi from wastewater
2017
Rajendran, Ranjith Kumar | Lin, Chu-Ching | Huang, Shir-Ly | Kirschner, Roland
4-t-Octylphenol (4-t-OP) has become a serious environmental concern due to the endocrine disruption in animals and humans. The biodegradation of 4-t-OP by pure cultures has been extensively investigated only in bacteria and wood-decaying fungi. In this study weisolated and identified 14 filamentous fungal strains from wastewater samples in Taiwan using 4-t-OP as a sole carbon and energy source. The isolates were identified based on sequences from different DNA regions. Of 14 fungal isolates, 10 strains grew effectively on solid medium with a wide variety of endocrine disrupting chemicals as the sole carbon andenergy source. As revealed by high-performance liquid chromatography analysis, the most effective 4-t-OP degradation (>70%) in liquid medium was observed in Fusarium falciforme after 15days. To our knowledge, this is the first report on the degradation of 4-t-OP as a sole carbon and energy source by non-ligninolytic fungi.
Afficher plus [+] Moins [-]Impact of a harbour construction on the benthic community of two shallow marine caves
2017
Nepote, Ettore | Bianchi, Carlo Nike | Morri, Carla | Ferrari, Marco | Montefalcone, Monica
Marine caves are unique and vulnerable habitats, threatened by multiple global and local disturbances. Whilst the effects of climate change on marine caves have already been investigated, no information exists about the effects of local human impacts, such as coastal development, on these habitats. This study investigated the impact of the construction of a touristic harbour on two shallow underwater marine caves in the Ligurian Sea (NW Mediterranean). As a standard methodology for monitoring marine caves does not exist yet, changes over time on the benthic community were assessed adopting two different non-taxonomic descriptors: trophic guilds and growth forms. Harbour construction caused an increase of sediment load within the caves, with a consequent decline of filter feeder organisms. Abundance of small organisms, such as encrusting and flattened sponges, was greatly reduced in comparison to organisms with larger and erect growth forms, such as domed mounds and pedunculated sponges. Our study indicated that growth forms and trophic guilds are effective descriptors for evaluating changes over time in marine caves, and could be easily standardised and applied in monitoring plans. In addition, as the harbour construction impacted differently according to the cave topography, the use of a systematic sampling in different zones of an underwater cave is recommended.
Afficher plus [+] Moins [-]Evaluating real-world emissions of light-duty gasoline vehicles with deactivated three-way catalyst converters
2017
Zheng, Xuan | Wu, Ye | Zhang, Shaojun | He, Liqiang | Hao, Jiming
Three-way catalyst (TWC) converter is one of the most important after-treatment device for modern light-duty gasoline vehicles (LDGVs), which can efficiently control exhaust emissions of carbon monoxide (CO), total hydrocarbons (THC) and nitrogen oxides (NOX). Nevertheless, a considerable part of in-use taxis in Beijing would operate with TWC purposely removed, which have been indicated by vehicular on-board diagnostic (OBD) systems. In light of high vehicle-use intensity for taxis, we recruited three China 4 non-TWC taxis and three China 4 normal taxis in a comparative experimental test by using a portable emissions measurement system (PEMS). The results indicated that non-TWC taxis emitted significantly higher emissions of air pollutants than normal taxis with TWC functioning. For example, average emission factors of non-TWC vehicles were comparable to emission levels of China 1 LDGVs measured in previous studies. By contrast, emissions from normal China 4 taxis were all below China 4 emission limits. Furthermore, an operating mode binning method and a micro-trip approach have been employed to link vehicle emissions with driving conditions. For non-TWC taxis, we identified strong correlations of all pollutant categories between emission factors and average speed. However, such correlations for normal taxis were less strong, in particular for CO and THC emissions that were hardly sensitive to speed changes. This phenomenon indicates that the role of traffic conditions in affecting real-world emissions would become weaker when TWC can effectively mitigate emissions. This paper highlights the importance of in-use emission inspection to avoid any “high emitters” that have violated regulation enforcement.
Afficher plus [+] Moins [-]Long-term perspective on the relationship between phytoplankton and nutrient concentrations in a southeastern Australian estuary
2017
Larsson, Michaela E. | Ajani, Penelope A. | Rubio, Ana M. | Guise, Kristy | McPherson, Ross G. | Brett, Steven J. | Davies, Kevin P. | Doblin, Martina A.
Sixteen years (1997–2013) of physicochemical, nutrient and phytoplankton biomass (Chlorophyll-a (Chl-a)) data and a decade (2003-2013) of phytoplankton composition and abundance data were analyzed to assess how the algal community in a temperate southeastern Australian estuary has responded to decreased chronic point source nitrogen loading following effluent treatment upgrade works in 2003. Nitrogen concentrations were significantly lower (P<0.05) following enhanced effluent treatment and Chl-a levels decreased (P<0.05) during the warmer months. Temperature and nutrient concentrations significantly influenced temporal changes of Chl-a (explaining 55% of variability), while salinity, temperature, pH and nutrient concentrations influenced phytoplankton abundance and composition (25% explained). Harmful Algal Bloom (HAB) dynamics differed between sites likely influenced by physical attributes of the estuary. This study demonstrates that enhanced effluent treatment can significantly decrease chronic point source nitrogen loading and that Chl-a concentrations can be lowered during the warmer months when the risk of blooms and HABs is greatest.
Afficher plus [+] Moins [-]Hypoxia off the Changjiang (Yangtze River) estuary and in the adjacent East China Sea: Quantitative approaches to estimating the tidal impact and nutrient regeneration
2017
Zhu, Zhuo-Yi | Wu, Hui | Liu, Su-Mei | Wu, Ying | Huang, Da-Ji | Zhang, Jing | Zhang, Guo-Sen
Large areas of hypoxia have been reported off The Changjiang Estuary and in the East China Sea. Five cruises, covering winter, spring, and summer, were carried out from 2007 to 2013 in this region, and in August 2013 (summer), an extensive hypoxic event (11,150km2) was observed, which was characterized by an estimated bulk oxygen depletion of 5.1 million tons. A strong tidal impact was observed associated with the bottom oxygen depletion, with the periodicity of diel variations in dissolved oxygen being 12h (i.e., similar to the tidal cycle). A conservative estimate of nutrient regeneration suggested that during the hypoxic event of August 2013, the amount of regenerated nitrogen (as nitrate) and phosphorus (as dissolved inorganic phosphorus) was 27,000–30,000 tons and 1300–41,000tons, respectively. Estimates of the absolute (bulk) regenerated nutrient fluxes were much greater than the conservative estimates.
Afficher plus [+] Moins [-]An ecosystem-based approach to assess the status of Mediterranean algae-dominated shallow rocky reefs
2017
Thibaut, Thierry | Blanfuné, Aurélie | Boudouresque, Charles F. | Personnic, Sébastien | Ruitton, Sandrine | Ballesteros, Enric | Bellan-Santini, Denise | Bianchi, Carlo Nike | Bussotti, Simona | Cebrian, Emma | Chemineé, Adrien | Culioli, Jean-Michel | Derrien-Courtel, Sandrine | Guidetti, Paolo | Harmelin-Vivien, M. L. (Mireille L.) | Hereu, Bernat | Morri, Carla | Poggiale, Jean-Christophe | Verlaque, Marc
A conceptual model was constructed for the functioning the algae-dominated rocky reef ecosystem of the Mediterranean Sea. The Ecosystem-Based Quality Index (reef-EBQI) is based upon this model. This index meets the objectives of the EU Marine Strategy Framework Directive. It is based upon (i) the weighting of each compartment, according to its importance in the functioning of the ecosystem; (ii) biological parameters assessing the state of each compartment; (iii) the aggregation of these parameters, assessing the quality of the ecosystem functioning, for each site; (iv) and a Confidence Index measuring the reliability of the index, for each site. The reef-EBQI was used at 40 sites in the northwestern Mediterranean. It constitutes an efficient tool, because it is based upon a wide set of functional compartments, rather than upon just a few species; it is easy and inexpensive to implement, robust and not redundant with regard to already existing indices.
Afficher plus [+] Moins [-]Identification of genotoxic compounds in crude oil using fractionation according to distillation, polarity and Kow
2017
Park, Shin Yeong | Lee, Hyo Jin | Khim, Jong Seong | Kim, Gi Beum
We examined the degree of DNA damage caused by fractions of crude oil in accordance with the boiling points, polarity and log Kow. Relatively high DNA damage was observed in the aromatic fraction (290–330°C) and resin and polar fraction (350–400°C). The resin and polar fraction showed relatively high genotoxicity compared with the aliphatic and aromatic fraction at the 1–4 log Kow range. At the 6–7 log Kow range, the aromatic fraction showed relatively high DNA damage compared with the aliphatic and resin and polar fraction. In particular, every detailed fraction in accordance with the log Kow values (aliphatic and aromatic (310–320°C) and resins and polar fractions (370–380°C)) showed one or less than one DNA damage. However, the fractions before separation in accordance with log Kow values (aliphatic and aromatic (310–320°C) and resin and polar (370–380°C) fractions) showed high DNA damage. Thus, we confirm the synergistic action between the detailed compounds.
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