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137Cs baseline levels in the Mediterranean and Black Sea: A cross-basin survey of the CIESM Mediterranean Mussel Watch programme
2008
Thébault, H. | Baena, A.M., | Andral, B. | Barisic, D. | Albaladejo, J.B. | Bologa, A.S. | Boudjenoun, R. | Delfanti, R. | Egorov, V.N. | El Khoukhi, T. | Florou, H. | Kniewald, G. | Noureddine, A. | Patrascu, V. | Pham, M.K. | Scarpato, A. | Stokozov, N.A. | Topcuoglu, S. | Warnau, M.
The common mussel Mytilus galloprovincialis was selected as unique biomonitor species to implement a regional monitoring programme, the CIESM Mediterranean Mussel Watch (MMW), in the Mediterranean and Black Seas. As of today, and upon standardization of the methodological approach, the MMW Network has been able to quantify 137Cs levels in mussels from 60 coastal stations and to produce the first distribution map of this artificial radionuclide at the scale of the entire Mediterranean and Black Seas. While measured 137Cs levels were found to be very low (usually <1 Bq kg-1 wet wt) 137Cs activity concentrations in the Black Sea and North Aegean Sea were up to two orders of magnitude higher than those in the western Mediterranean Basin. Such effects, far from representing a threat to human populations or the environment, reflect a persistent signature of the Chernobyl fallout in this area. © 2007 Elsevier Ltd. All rights reserved.
اظهر المزيد [+] اقل [-]137Cs baseline levels in the Mediterranean and Black Sea: A cross-basin survey of the CIESM Mediterranean Mussel Watch programme
2008
Thébault, H. | Baena, A.M., Rodriguez y | Andral, B. | Barisic, D. | Albaladejo, J.B. | Bologa, A.S. | Boudjenoun, R. | Delfanti, R. | Egorov, V.N. | El Khoukhi, T. | Florou, H. | Kniewald, G. | Noureddine, A. | Patrascu, V. | Pham, M.K. | Scarpato, A. | Stokozov, N.A. | Topcuoglu, S. | Warnau, M. | Laboratoire d'étude radioécologique du milieu continental et marin (IRSN/DEI/SESURE/LERCM) ; Service d'étude et de surveillance de la radioactivité dans l'environnement (IRSN/DEI/SESURE) ; Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN) | Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER) | Center for Marine and Environmental Research ; Rudjer Boskovic Institute [Zagreb] | Instituto Español de Oceanografía - Spanish Institute of Oceanography (IEO) ; Consejo Superior de Investigaciones Cientificas [España] = Spanish National Research Council [Spain] (CSIC) | National Institute for Marine Research and Development "Grigore Antipa" (NIMRD) | Agenzia Nazionale per le nuove Tecnologie, l’energia e lo sviluppo economico sostenibile = Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA) | NATIONAL ACADEMY OF SCIENCES OF THE UKRAINE KHARKOV UKR ; Partenaires IRSTEA ; Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) | Centre National de l'Énergie, des Sciences et des Techniques Nucléaires = National Center for Energy, Science and Nuclear Techniques (CNESTEN) | National Center for Scientific Research "Demokritos" (NCSR) | Marine Environment Laboratories [Monaco] (IAEA-MEL) ; International Atomic Energy Agency [Vienna] (IAEA) | I.C.R.A.M. - Central Institute for Applied Marine Research ; I.C.R.A.M. - Central Institute for Applied Marine Research
International audience | The common mussel Mytilus galloprovincialis was selected as unique biomonitor species to implement a regional monitoring programme, the CIESM Mediterranean Mussel Watch (MMW), in the Mediterranean and Black Seas. As of today, and upon standardization of the methodological approach, the MMW Network has been able to quantify 137Cs levels in mussels from 60 coastal stations and to produce the first distribution map of this artificial radionuclide at the scale of the entire Mediterranean and Black Seas. While measured 137Cs levels were found to be very low (usually <1 Bq kg-1 wet wt) 137Cs activity concentrations in the Black Sea and North Aegean Sea were up to two orders of magnitude higher than those in the western Mediterranean Basin. Such effects, far from representing a threat to human populations or the environment, reflect a persistent signature of the Chernobyl fallout in this area. © 2007 Elsevier Ltd. All rights reserved.
اظهر المزيد [+] اقل [-]The effect of nitrogen additions on oak foliage and herbivore communities at sites with high and low atmospheric pollution
2008
Jones, M.E. | Paine, T.D. | Fenn, M.E.
To evaluate plant and herbivore responses to nitrogen we conducted a fertilization study at a low and high pollution site in the mixed conifer forests surrounding Los Angeles, California. Contrary to expectations, discriminant function analysis of oak herbivore communities showed significant response to N fertilization when atmospheric deposition was high, but not when atmospheric deposition was low. We hypothesize that longer-term fertilization treatments are needed at the low pollution site before foliar N nutrition increases sufficiently to affect herbivore communities. At the high pollution site, fertilization was also associated with increased catkin production and higher densities of a byturid beetle that feeds on the catkins of oak. Leaf nitrogen and nitrate were significantly higher at the high pollution site compared to the low pollution site. Foliar nitrate concentrations were positively correlated with abundance of sucking insects, leafrollers and plutellids in all three years of the study.
اظهر المزيد [+] اقل [-]Short- and medium-term effects of experimental nitrogen fertilization on arthropods associated with Calluna vulgaris heathlands in north-west Spain
2008
Cuesta, D. | Taboada, A. | Calvo, L. | Salgado, J.M.
We studied the short- and medium-term effects of experimental nitrogen fertilization (3 and 15 months after the treatment) on the arthropods of Calluna vulgaris heathlands in NW Spain. Three heathland sites were selected with two permanent plots per site: control and fertilized. Ammonium nitrate fertilizer (56 kg N ha-1 yr-1) was applied monthly and insects were caught using pitfall traps. We found mainly species-level responses to nitrogen addition. Seven species (e.g. Lochmaea suturalis) showed a consistent trend (benefited or harmed) in both periods and were proposed as possible reliable indicators of the effects of nitrogen deposition in these ecosystems. We also found variable arthropod trophic-group responses: (a) herbivores (leaf beetles, true bugs) increased in abundance on a short-term scale; (b) predators (carabid beetles, true bugs) showed opposite and less clear responses in both periods. Further long-term studies are needed to determine the mechanisms underlying the observed arthropod responses. We observed consistent species-level and variable trophic-group responses to nitrogen addition in one of the southern-most locations for Calluna vulgaris heathlands within Europe.
اظهر المزيد [+] اقل [-]Long-term effects of aided phytostabilisation of trace elements on microbial biomass and activity, enzyme activities, and composition of microbial community in the Jales contaminated mine spoils
2008
Renella, G. | Landi, L. | Ascher, J. | Ceccherini, M.T. | Pietramellara, G. | Mench, M. | Nannipieri, P.
We studied the effectiveness of remediation on microbial endpoints, namely microbial biomass and activity, microbial and plant species richness, of an As-contaminated mine spoil, amended with compost (C) alone and in combination with beringite (B) or zerovalent iron grit (Z), to increase organic matter content and reduce trace elements mobility, and to allow Holcus lanatus and Pinus pinaster growth. Untreated spoil showed the lowest microbial biomass and activity and hydrolase activities, and H. lanatus as sole plant species, whereas the presented aided phytostabilisation option, especially CBZ treatment, significantly increased microbial biomass and activity and allowed colonisation by several plant species, comparable to those of an uncontaminated sandy soil. Microbial species richness was only increased in spoils amended with C alone. No clear correlation occurred between trace element mobility and microbial parameters and plant species richness. Our results indicate that the choice of indicators of soil remediation practices is a bottleneck. Organo-mineral amendment and revegetation of a gold mine spoil increased microbial activity but did not increase microbial species richness.
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