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Modelling the impact of climate change and atmospheric N deposition on french forests biodiversity
2015
Rizzetto, Simon | Belyazid, Salim | Gégout, Jean-Claude | Nicolas, Manuel | Alard, Didier | Corcket, Emmanuel | Gaudio, Noémie | Sverdrup, Harald | Probst, Anne | Ecotoxicologie & Santé des écosystèmes - ECSECO (ECI) ; Laboratoire Ecologie Fonctionnelle et Environnement (LEFE) ; Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Institut National de la Recherche Agronomique (INRA) | Belyazid Consulting and Communication AB | Laboratoire d'Etudes des Ressources Forêt-Bois (LERFoB) ; Institut National de la Recherche Agronomique (INRA)-AgroParisTech | Office National des Forêts (ONF) | Biodiversité, Gènes & Communautés (BioGeCo) ; Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB) | Skane University Hospital [Lund] | International Union of Forest Research Organisations (IUFRO). AUT.
Since the 1980’s, within the Geneva Convention on Long-Range Transboundary Air Pollution, European countries have joined their efforts to abate atmospheric acid pollution. Nevertheless, nitrogen emissions and depositions remain significant under ongoing climate change. Nitrogen atmospheric deposition is known to severely impact ecosystem functioning by influencing soil biogeochemistry, nutrients balance and, consequently, tree growth, forest health and biodiversity. The concept of “critical loads” was used and models were improved to mitigate the impacts of N deposition, by considering conjointly effects of climate change and N atmospheric deposition, to assess the evolution of forest ecosystem status over time. The purpose of this study is to predict forest vegetation response to the combine effects of nitrogen atmospheric deposition and climate change by using a dynamic coupled biogeochemical-ecological model (ForSAFE-Veg). The Veg module is composed of 476 understory plant species representative of the main French forest ecosystems, and parameterized for a set of environmental factors based on expert advices. In this study, we propose a new parameterization for six main factors using statistical regressions models based on measured data for about 4000 forest sites. After validation using another independent set of vegetation relevés, the biogeochemical model ForSAFE-Veg was run using the most appropriate Veg module, on three forest sites from the french ICP Forest network. Changes in biodiversity were estimated by analysing the evolution of plants cover over100 years, and considering the impacts of climate change and atmospheric nitrogen deposition scenarios separately and conjointly. The modelling outputs were considered at both species and ecological functional groups scales, to evaluate their relevance in characterizing nitrogen deposition influence on biodiversity. This will allow generalizing this approach to other species for which environmental factors are not easy to parameterize.
Show more [+] Less [-]Evaluation of highly mobile fraction of trace elements in PM10 collected in Upper Silesia (Poland): Preliminary results
2015
Zajusz-Zubek, Elwira | Mainka, Anna | Korban, Zygmunt | Pastuszka, Józef S.
The amount of the soluble fraction of trace elements released from inhaled particulate matter seems to be one of the key factors of the toxicity of these particles. This study reports the concentrations of PM10 and trace elements in total and water-soluble fractions (bioavailable form). Weekly samples were collected at two rural sites in Upper Silesia, Poland. Measurements were carried out from April to August 2013, divided between heating and non-heating sessions. During heating sessions, the concentrations of PM10 in selected sites varied in the range of 32.88–48.70 μg m−3, while for the non-heating sessions the range was 16.14–27.89 μg m−3.Selected PM10 samples (characteristic for both sessions) were determined by means of total and water-soluble content of eight trace elements. The elements are characteristic of carcinogenic (As, Cr, Cd and Ni), probably carcinogenic (Co and Pb) and toxic (Mn and Sb) groups. The analyses of the mineralized samples as well as the water-soluble fractions were carried out by ICP-MS method using a Varian 810 MS.The total concentration of carcinogenic Cd, Cr and Ni during non-heating sessions was 2.81, 7.97 and 4.82 ng m−3, respectively. While during heating sessions the total content was twice as high. Similar relation was observed for the concentration of PM10. The concentration of the soluble fraction of these elements in the atmospheric air in heating sessions was 1.62, 0.75, 2.20, 1.79, 1.85 ng m−3 for As, Cr, Pb, Mn, Sb, respectively and remained almost the same as in non-heating sessions. Lower levels of Ni and Cd (0.15 and 0.11 ng m−3) were determined during heating sessions. The obtained data indicate that during heating periods these elements are probable present mainly in other fractions with lower mobility, so less harmful to human health.
Show more [+] Less [-]Polluter identification with spaceborne radar imagery, AIS and forward drift modeling
2015
Longépé, N. | Mouche, A.A. | Goacolou, M. | Granier, N. | Carrère, L. | Lebras, J.Y. | Lozach, P. | Besnard, S.
This study defines and assesses a new operational concept to identify the origin of pollution at sea, based on Synthetic Aperture Radar, Automatic Identification System, and a forward drift model. As opposed to traditional methodologies where the SAR detected pollution is backtracked in the past, our approach assumes that all the vessels pollute all along their way. Based on all the AIS data flows, the forward-tracked simulated pollutions are then compared to the detected pollution, and the potential polluter can be finally identified. Case studies are presented to showcase its usefulness in a variety of maritime situations with a focus on orphan pollutions in a dense traffic area. Out of the identification of the suspected polluters, the age and eventually the type of the pollution can be retrieved.
Show more [+] Less [-]Satellite-based observations of unexpected coastal changes due to the Saemangeum Dyke construction, Korea
2015
Lee, Yoon-Kyung | Ryu, Joo-Hyung | Choi, Jong-Kuk | Lee, Seok | Woo, Han-Jun
Spatial and temporal changes around an area of conventional coastal engineering can be easily observed from field surveys because of the clear cause-and-effect observable in the before and after stages of the project. However, it is more difficult to determine environmental changes in the vicinity of tidal flats and coastal areas that are a considerable distance from the project. To identify any unexpected environmental impacts of the construction of Saemangeum Dyke in the area, we examined morphological changes identified by satellite-based observations through a field survey on Gomso Bay tidal flats (15km from Saemangeum Dyke), and changes in the suspended sediment distribution identified by satellite-based observations through a hydrodynamic analysis in the Saemangeum and Gomso coastal area. We argue that hydrodynamic changes due to conventional coastal engineering can affect the sedimentation pattern in the vicinity of tidal flats. We suggest that the environmental impact assessment conducted before a conventional coastal engineering project should include a larger area than is currently considered.
Show more [+] Less [-]Impact of cigarette butt leachate on tidepool snails
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.
Show more [+] Less [-]Role of entrained droplet oil on the bioavailability of petroleum substances in aqueous exposures
2015
Redman, A.D.
Bioavailability of petroleum substances is a complex issue that is affected by substance composition, the physicochemical properties of the individual constituents, and the exposure preparation system. The present study applies mechanistic fate and effects models to characterize the role of droplet oil on dissolved exposure and predicted effects from both neat and weathered crude oils, and refined fuel oils. The main effect from droplet oil is input of additional dissolved hydrocarbons to the exposure system following preparation of the initial stock solution. Toxicity was characterized using toxic units (TU) and shows that replenishment of bioavailable hydrocarbons by droplets in toxicity tests with low droplet content (e.g., <1mg/L) is negligible, consistent with typical exposure conditions following open ocean oil spills. Further, the use of volumetric exposure metrics (e.g., mg/L) introduces considerable variability and the bioavailability-based metrics (e.g., TUs) provide a more consistent basis for understanding oil toxicity data.
Show more [+] Less [-]Geochemical and isotopic data for restricting seawater intrusion and groundwater circulation in a series of typical volcanic islands in the South China Sea
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.
Show more [+] Less [-]Impact of seaweed beachings on dynamics of δ15N isotopic signatures in marine macroalgae
2015
Lemesle, Stéphanie | Mussio, Isabelle | Rusig, Anne-Marie | Menet-Nédélec, Florence | Claquin, Pascal
A fine-scale survey of δ15N, δ13C, tissue-N in seaweeds was conducted using samples from 17 sampling points at two sites (Grandcamp-Maisy (GM), Courseulles/Mer (COU)) along the French coast of the English Channel in 2012 and 2013. Partial triadic analysis was performed on the parameter data sets and revealed the functioning of three areas: one estuary (EstA) and two rocky areas (GM∗, COU∗). In contrast to oceanic and anthropogenic reference points similar temporal dynamics characterized δ15N signatures and N contents at GM∗ and COU∗. Nutrient dynamics were similar: the N-concentrations in seawater originated from the River Seine and local coastal rivers while P-concentrations mainly from these local rivers. δ15N at GM∗ were linked to turbidity suggesting inputs of autochthonous organic matter from large-scale summer seaweed beachings made up of a mixture of Rhodophyta, Phaeophyta and Chlorophyta species. This study highlights the coupling between seaweed beachings and nitrogen sources of intertidal macroalgae.
Show more [+] Less [-]Ranking the suitability of common urban tree species for controlling PM2.5 pollution
2015
Yang, Jun | Chang, Yamin | Yan, Pengbo
Pollution caused by particles with aerodynamic diameters less than 2.5μm (PM2.5) is now a major environmental problem in many Asian cities. Planting more trees has been suggested as an unconventional approach to alleviate the problem. In this study, we developed a ranking approach to evaluate the PM2.5 removal efficiency, negative impacts on air quality, and the suitability to urban environments of commonly occurring urban tree species. The results showed that the most frequently occurring tree species in global cities were not the best performers in removing PM2.5. Among the ten most frequently occurring tree species, only London plane (Platanus acerifolia (Aiton) Wild.), silver maple (Acer saccharinum L.) and honey locust (Gleditsia triacanthos L.) were ranked above average. However, there is great potential for improving the removal of PM2.5 from urban air by using species that have high PM2.5 removal efficiency, especially conifer species. Use of conifer species requires choosing the correct gender and matching trees with appropriate sites. The results from this study can assist environmental management agencies in the selection of tree species for urban greening projects focusing on PM2.5 control.
Show more [+] Less [-]Urban air quality management-A review
2015
Gulia, Sunil | Shiva Nagendra, S.M. | Khare, Mukesh | Khanna, Isha
Urban air quality management plan (UAQMP) is an effective and efficient tool employed in managing acceptable urban air quality. However, the UAQM practices are specific to a country’s needs and requirements. Majority of the developed countries have full–fledged UAQMP with a regulatory management framework. However, developing countries are still working in formulating the effective and efficient UAQMPs to manage their deteriorating urban air environment. The first step in the process of formulation of UAQMP is to identify the air quality control regions based on ambient air quality status and second, initiate a time bound program involving all stakeholders to develop UAQMPs. The successful implementation of UAQMPs depends on the strength of its key components, e.g. goal/objective, monitoring network, emission inventory, air quality modeling, control strategies and public participation. This paper presents a comprehensive review on UAQMPs, being implemented worldwide at different scales e.g., national (macro), city (medium), and local (micro).
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