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Deperissement des forets et pollution atmospherique: ce que nous avons appris (Programme DEFORPA 1984-1991).
1992
Landmann G.
Forest decline and soil nutritional problems in Pacific areas.
1990
Mueller Dombois D.
Liming effects on some chemical and biological parameters of soil (spodosols and histosols) in a hardwood forest watershed.
1990
Yavitt J.B. | Newton R.M.
Relative importance of natural and anthropogenic proton sources in soils in the Netherlands.
1986
Vries W. de | Breeuwsma A.
Acidity status of surface waters in Massachusetts.
1992
Walk M.F.I. | Godfrey P.J. | Ruby A. III | Zajicek O.T. | Mattson M.
Soil Solution Nitrogen and Cations Influenced by (NH4)2SO4 Deposition in a Coniferous Forest
1997
Carnol, Monique | Ineson, Phil | Dickinson, A. L.
peer reviewed | The effects of chronically enhanced (NH(4))(2)SO(4) deposition on ion concentrations in soil solution and ionic fluxes were investigated in a Picea abies plot at Grizedale forest, NW England. Soil cores closed at the base and containing a ceramic suction cup sampler were 'roofed' and watered every 2 weeks with bulk throughfall collected in the field. Treatments consisted of the inclusion of living roots from mature trees in the lysimeters and increasing (NH(4))(2)SO(4) deposition (NS treatment) to ambient + 75 kg N ha(-1) a(-1). Rainfall, throughfall and soil solutions were collected every 2 weeks during 18 months, and analysed for major cations and anions. NO(3)(-) fluxes significantly increased following NS treatment, and were balanced by increased Al(3+) losses. Increased SO(4)(2-) concentrations played a minor role in controlling soil solution cation concentrations. The soil exchange complex was dominated by Al and, during the experimental period, cores of all treatments 'switched' from Ca(2+) to Al(3+) leaching, leading to mean [Formula: see text] molar ratios in soil solution of NS treated cores of 0.24. The experiment confirmed that the most sensitive soils to acidification (through deposition or changing environmental conditions) are those with low base saturation, and with a pH in the lower Ca, or Al buffer ranges.
Afficher plus [+] Moins [-]Habitat selection by marine larvae in changing chemical environments
2017
Lecchini, David | Dixson, Danielle L. | Lecellier, Gael | Roux, Natacha | Frederich, Bruno | Besson, Marc | Tanaka, Y. | Banaigs, Bernard | Nakamura, Yohei | AFFISH-RC - Applied and Fundamental FISH Research Center - ULiège
peer reviewed | The replenishment and persistence of marine species is contingent on dispersing larvae locating suitable habitat and surviving to a reproductive stage. Pelagic larvae rely on environmental cues to make behavioural decisions with chemical information being important for habitat selection at settlement. We explored the sensory world of crustaceans and fishes focusing on the impact anthropogenic alterations (ocean acidification, red soil, pesticide) have on conspecific chemical signals used by larvae for habitat selection. Crustacean (Stenopus hispidus) and fish (Chromis viridis) larvae recognized their conspecifics via chemical signals under control conditions. In the presence of acidified water, red soil or pesticide, the ability of larvae to chemically recognize conspecific cues was altered. Our study highlights that recruitment potential on coral reefs may decrease due to anthropogenic stressors. If so, populations of fishes and crustaceans will continue their rapid decline; larval recruitment will not replace and sustain the adult populations on degraded reefs.
Afficher plus [+] Moins [-]Nitrogen deposition threatens species richness of grasslands across Europe
2010
Stevens, Carly J. | Dupre, Cecilia | Dorland, Edu | Gaudnik, Cassandre | Gowing, David J.G. | Bleeker, Albert | Diekmann, Martin | Alard, Didier | Bobbink, Roland | Fowler, David | Corcket, Emmanuel | Mountford, J. Owen | Vandvik, Vigdis | Aarrestad, Per Arild | Muller, Serge | Dise, Nancy B. | Open University | Lancaster Environment Centre ; Lancaster University | University of Bremen | Biodiversité, Gènes & Communautés (BioGeCo) ; Institut National de la Recherche Agronomique (INRA)-Université de Bordeaux (UB) | Department of Air Quality and Climate Change ; Energy Research Centre for the Netherlands | Radboud University [Nijmegen] | Natural Environment Research Council (NERC) | Department of Biology ; University of Washington [Seattle] | Norwegian Institute for Nature Research (NINA) | Centre National de la Recherche Scientifique (CNRS) | University of Manchester [Manchester]
International audience | Evidence from an international survey in the Atlantic biogeographic region of Europe indicates that chronic nitrogen deposition is reducing plant species richness in acid grasslands. Across the deposition gradient in this region (2–44 kg N ha−1 yr−1) species richness showed a curvilinear response, with greatest reductions in species richness when deposition increased from low levels. This has important implications for conservation policies, suggesting that to protect the most sensitive grasslands resources should be focussed where deposition is currently low. Soil pH is also an important driver of species richness indicating that the acidifying effect of nitrogen deposition may be contributing to species richness reductions. The results of this survey suggest that the impacts of nitrogen deposition can be observed over a large geographical range. Atmospheric nitrogen deposition is reducing biodiversity in grasslands across Europe.
Afficher plus [+] Moins [-]Habitat selection by marine larvae in changing chemical environments
2016
Lecchini, David | Dixson, D.L. | Lecellier, Gaël | Roux, Natacha | Frédérich, Bruno | Besson, Marc | Tanaka, Y. | Banaigs, B. | Nakamura, Y. | Centre de recherches insulaires et observatoire de l'environnement (CRIOBE) ; Université de Perpignan Via Domitia (UPVD)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire d'Excellence CORAIL (LabEX CORAIL) ; Institut de Recherche pour le Développement (IRD)-Université des Antilles et de la Guyane (UAG)-École des hautes études en sciences sociales (EHESS)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de La Réunion (UR)-Université de la Polynésie Française (UPF)-Université de la Nouvelle-Calédonie (UNC)-Institut d'écologie et environnement-Université des Antilles (UA) | School of Marine Science and Policy ; University of Delaware [Newark] | Université Paris-Saclay | Biologie intégrative des organismes marins (BIOM) ; Observatoire océanologique de Banyuls (OOB) ; Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) | Laboratoire de Morphologie Fonctionnelle et Evolutive ; Université de Liège | Institut de Génomique Fonctionnelle de Lyon (IGFL) ; École normale supérieure de Lyon (ENS de Lyon)-Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL) ; Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS) | sesoko station ; University of the Ryukyus [Okinawa] | Graduate School of Kuroshio Science ; Kochi University
International audience | The replenishment and persistence of marine species is contingent on dispersing larvae locating suitable habitatand surviving to a reproductive stage. Pelagic larvae rely on environmental cues to make behavioural decisionswith chemical information being important for habitat selection at settlement. We explored the sensory worldof crustaceans and fishes focusing on the impact anthropogenic alterations (ocean acidification, red soil, pesti-cide) have on conspecific chemical signals used by larvae for habitat selection. Crustacean (Stenopus hispidus)and fish (Chromis viridis) larvae recognized their conspecifics via chemical signals under control conditions. Inthe presence of acidified water, red soil or pesticide, the ability of larvae to chemically recognize conspecificcues was altered. Our study highlights that recruitment potential on coral reefs may decrease due to anthropo-genic stressors. If so, populations of fishes and crustaceans will continue their rapid decline; larval recruitmentwill not replace and sustain the adult populations on degraded reefs
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