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  • Declining trend in the C 13/C 12 ratio of atmospheric carbon dioxide from tree rings of South African Widdringtonia cedarbergensis
  • Action anthropique ; Afrique du Sud ; Analyse isotopique ; Cape Province ; Carbone ; Dendroclimatologie ; Dendrologie ; Géochimie ; Géochronologie ; Paléoclimat ; Précipitation
  • Cape Province ; Carbon ; Dendroclimatology ; Dendrology ; Geochemistry ; Geochronology ; Human impact ; Isotope analysis ; Palaeoclimate ; Precipitation ; South Africa
  • This paper reports the first high-resolution (annual) C 13/C 12 chronology for both Africa and the Southern Hemisphere. The 77-yr stable carbon isotope chronology was developed from 6 Widdringtonia cedarbergensis trees from a site in the Cedarberg
  • Mountains, Western Cape Province, South Africa. The results indicate that C 13/C 12 ratios are not different from 1900 to 1949. After 1949, however, values become significantly more negative to 1977. This decline can be related to the anthropogenic impact
  • Carbon isotopes in the rivers from the Lesser Antilles : origin of the carbonic acid consumed by weathering reactions in the Lesser Antilles
  • Analyse isotopique ; Antilles ; Carbone ; Carbone 13 ; Cours d'eau ; Dioxyde de carbone ; Eau souterraine ; Erosion chimique ; Géochimie ; Météorisation ; Petites Antilles ; Roche volcanique ; Traceur
  • Carbon ; Carbon 13 ; Carbon dioxide ; Chemical erosion ; Geochemistry ; Isotope analysis ; Lesser Antilles ; Stream ; Tracer ; Underground water ; Volcanic rock ; Weathering ; West Indies
  • The AA. use carbon isotopes in the dissolved load of rivers from the Lesser Antilles volcanic arc (Guadeloupe, Martinique and Dominica islands) to constrain the source of the carbon dioxide (CO2) involved in the neutralization reactions during water
  • weathering is an additional parameter that could explain the high weathering rates of volcanic rocks. The study also shows that a significant part of the carbon degassed from the Earth's interior is not released as CO2 to the atmosphere, but as DIC(dissolved
  • inorganic carbon)to the ocean because it interacts with the groundwater system. This study calls for a better understanding of the contributions of deep carbon to the hydrosphere and its influence on the development of the Critical Zone.
  • Can δ13C abundance, water-soluble carbon, and light fraction carbon be potential indicators of soil organic carbon dynamics in Zoigê wetland?
  • Analyse de régression ; Analyse isotopique ; Carbone ; Carbone 13 ; Changement climatique ; Chine ; Dégradation de l'environnement ; Milieu humide ; Montagne ; Plateau ; Propriétés du sol ; Qinghai ; Tibet
  • Carbon ; Carbon 13 ; China ; Climatic change ; Environmental degradation ; Humid environment ; Isotope analysis ; Mountain ; Plateau ; Qinghai ; Regression analysis ; Soil properties ; Tibet
  • In this study, four wetland sites and one degraded wetland site in the Zoigê alpine wetland, located at the Qinghai-Tibet Plateau, were selected to investigate the relationships of stable isotope and labile organic carbon dynamics with groundwater
  • elevation or water table level. The AA.also examine if the δ13C abundance, soil water soluble organic carbon (WSOC), light fraction organic carbon (LFOC), can be used as potential indicators of soil organic carbon (SOC) dynamics in these wetland sites
  • δC 13 of loess organic matter as a potential proxy for paleoprecipitation
  • Allemagne ; Analyse isotopique ; Carbone ; Indice climatique ; Loess ; Matière organique ; Méthodologie ; Paléo-environnement ; Paléoprécipitation ; Précipitation ; Rhin ; Vallée
  • Carbon ; Climatic index ; Germany ; Isotope analysis ; Loess ; Methodology ; Organic materials ; Palaeo-environment ; Precipitation ; Rhine ; Valley
  • an independant method. Thus, δC 13 of loess organic matter can be used as a proxy for paleoprecipitation.
  • Carbone 13 ; Carbone 14 ; Complexe aquifère ; Eau souterraine ; Grès ; Géographie physique ; Hydrogéologie ; Nappe aquifère ; Recharge naturelle ; Roche carbonatée ; Technique de recherche ; Teneur isotopique ; Tritium
  • Amino acids and stable carbon isotope distributions in Taihu Lake, China, over the last 15,000 years, and their paleoecological implications
  • Aminostratigraphie ; Analyse isotopique ; Carbone ; Chine ; Géochimie ; Holocène ; Jiangsu ; Lac ; Paléo-écologie ; Quaternaire ; Sédiment lacustre ; Variation climatique ; Zhejiang
  • Aminostratigraphy ; Carbon ; China ; Climatic variation ; Geochemistry ; Holocene ; Isotope analysis ; Jiangsu ; Lacustrine sediment ; Lake ; Palaeo-ecology ; Quaternary ; Zhejiang
  • Amino acid, organic nitrogen, and stable carbon isotope (C 13/C 12) profiles through a core from East Taihu Lake are interpreted in terms of paleoecology and paleoclimate over the last 15,000 yr. The average δ C 13 values from a core from West Taihu
  • Lake are evidently higher than values from East Taihu Lake, showing that East Taihu Lake sediments are related to heterotrophic carbon sources from the watershed. The western part of Taihu Lake, by contrast, has been a lacustrine environment since
  • Factors controlling carbonate dissolution rates quantified in a field test in the Austrian alps
  • Alpes ; Autriche ; Bassin-versant ; Bilan de masse ; Carbonate ; Dissolution karstique ; Expérimentation de terrain ; Géochimie ; Karst ; Lithologie
  • Alps (The) ; Austria ; Carbonate ; Carbonate dissolution ; Field experiment ; Geochemistry ; Glacier mass balance ; Karst ; Lithology ; Watershed
  • data, and limestone pedestals. For the field test, 70 carbonate tablets were exposed to natural dissolution for 1 year, over 13 sites on the north slope of the Hochschwab Massif in the Austrian Alps. The influences of altitude, subsoil vs. sub-aerial
  • The aims of this study were to investigate the factors controlling carbonate dissolution within one restricted area, the carchment area of a major alpine karst spring, by comparing the results from carbonate tables, mass-balance from hydrological
  • Holocene landscape history and palaeohydrology evidenced by stable carbon isotope (δ C 13)analysis of alluvial sediments in the Mbari valley (5°N/23°E), Central African Republic
  • Analyse isotopique ; Carbone ; Centrafricaine république ; Ecoulement ; Forêt tropicale ; Holocène ; Limite ; Paléo-environnement ; Paléohydrologie ; Réseau de drainage ; Savane ; Végétation
  • Boundary ; Carbon ; Central African Republic ; Drainage network ; Holocene ; Isotope analysis ; Palaeo-environment ; Palaeohydrology ; Runoff ; Savanna ; Tropical rain forest ; Vegetation
  • an important role on the runoff processes and on the discharge of the draining river systems. Therefore, this study focuses on the examination of alluvial soils and the determination of stable carbon isotopes of organic sediments on the Mbomou plateau
  • Paleoclimatic reconstruction in northern Oman based on carbonates from hyperalkaline groundwaters
  • Analyse isotopique ; Carbonate ; Carbone 13 ; Datation C 14 ; Eau souterraine ; Géographie physique ; Hydrogéologie ; Oman ; Oxygène 18 ; Paléo-environnement ; Paléoclimatologie ; Quaternaire ; Travertin ; Variation climatique
  • Stable isotope ratios of carbon in phytoliths as a quantitative method of monitoring vegetation and climate change
  • Analyse isotopique ; Carbone 13 ; Etats-Unis ; Great Plains ; Géochimie ; Géographie de l'Amérique ; Holocène ; Méthodologie ; Paléo-environnement ; Paléosol ; Phytolite ; Quaternaire ; Variation climatique ; Végétation
  • The purpose of this work is to explore the possibility of using the stable isotopic composition of carbon in phytoliths to reconstruct aspects of paleoenvironmental conditions. The basis for this approach is related to the influence of climate
  • Late Pleistocene paleoclimatology of the Central Equatorial Pacific : a quantitative record of eolian and carbonate deposition
  • Carbone 13 ; Granulométrie ; Géographie physique ; Isotope ; Oxygène 18 ; Pacifique ; Pacifique équatorial ; Paléo-environnement ; Paléoclimatologie ; Pléistocène supérieur
  • Par l'étude des rapports isotopiques O18/O16 et C13/C12, des pourcentages et des vitesses d'accumulation des carbonates et des matériaux éoliens, établissement d'une chronologie des événements paléoclimatiques pour les 950 000 dernières années.
  • Relationship between climate and vegetation and the stable carbon isotope chemistry of soils in the eastern Mojave Desert, Nevada
  • Carbone 13 ; Climat ; Désert ; Etats-Unis ; Géochimie ; Géographie de l'Amérique ; Isotope ; Mojave Desert ; Nevada ; Paléo-environnement ; Pédogenèse ; Sol ; Végétation
  • It appears that in the sparsely vegetated Mojave Desert, the C13/C12 of pedogenic carbonate is controlled by differences in plant density and biological activity. This relationship may provide a tool for assessing past vegetational densities
  • Oxygen-18, deuterium and carbon-13 content of organic matter from litter and humus layers in podzolic soils
  • tendent à montrer que la relation qui existe entre la composition isotopique de la cellulose et certains paramètres du milieu n'est pas masquée par le début de décomposition subie par la litière dans le sol. Les teneurs en carbone 13 sont indépendantes.
  • Analyse isotopique ; Biostratigraphie ; Carbone 13 ; Géographie de l'Asie ; Israël ; Mollusque ; Oxygène 18 ; Paléoclimatologie ; Pléistocène ; Quaternaire
  • A l'aide des données isotopiques (oxygène 18 et carbone 13), de l'étude des changements de forme des coquilles de Melanopsis et de la disparition soudaine de Viviparus, reconstitution des plus importants cycles climatiques du Pléistocène.
  • The implications for paleodietary and paleoclimatic reconstructions of intrapopulation variability in the oxygen and carbon isotopes of teeth from modern feral horses
  • Analyse isotopique ; Carbone ; Cheval ; Dent ; Etats-Unis ; North Carolina ; Oxygène 18 ; Paléo-environnement ; Paléo-écologie ; Quaternaire ; Zone tempérée
  • Carbon ; Horse ; Isotope analysis ; North Carolina ; Oxygen 18 ; Palaeo-ecology ; Palaeo-environment ; Quaternary ; Temperate zone ; United States of America
  • The AA. analyze tooth enamel from feral horses from a temperate climate : Shackleford Banks, North Carolina (USA). Enamel δC 13 values are compared with the values of local plants. Enamel δO 18 values are compared with values of surface water
  • samples and with analyses of the δO 18 values of precipitation at nearby Hatteras, North Carolina. The variability of both δO 18 and the δC 13 values among individuals within this population demonstrates that horses from relatively homogenous temperate
  • Modern stable isotopice (δO 18, δH 2, δC 13) variation in terrestrial, fluvial, estuarine and marine waters from north-central Sarawak,
  • Analyse isotopique ; Bassin-versant ; Carbone ; Cycle de l'eau ; Cycle du carbone ; Eau ; Grotte ; Hydrogène ; Hydrologie ; Malaisie ; Oxygène 18 ; Paléo-environnement ; Quaternaire ; Sarawak ; Zone intertropicale
  • Carbon ; Carbon cycle ; Cave ; Hydrology ; Isotope analysis ; Malaysia ; Oxygen 18 ; Palaeo-environment ; Quaternary ; Sarawak ; Tropical zone ; Water ; Water cycle ; Watershed
  • Palustrine carbonates and pedogenic calcretes in the Çal basin of SW Anatolia : Implications for the Plio-Pleistocene regional climatic pattern in the eastern Mediterranean
  • Analyse isotopique ; Anatolie ; Carbonate ; Carbone 13 ; Croûte calcaire ; Domaine méditerranéen ; Oxygène 18 ; Paléo-environnement ; Paléoclimat ; Pliocène ; Pléistocène ; Sédimentologie ; Turquie
  • Anatolia ; Calcrete ; Carbon 13 ; Carbonate ; Isotope analysis ; Mediterranean area ; Oxygen 18 ; Palaeo-environment ; Palaeoclimate ; Pleistocene ; Pliocene ; Sedimentology ; Turkey
  • deposits above as a single sedimentary unit resting on top of floodplain fines and restricted to the basin center. The stable isotopic analysis of the palustrine carbonates and pedogenic calcretes displays a wide range of values and the lack of significant
  • δ18 O-δ13 C may indicate subhumid conditions or significant diagenetic alteration. The δ13 C values of these carbonates, organic δ13 C data from calcretes and floral remains indicate that the landscapes were dominated by C3 forest plants.
  • 14C offsets and apparently non-synchronous 18O stratigraphies between nannofossil and foraminiferal pelagic carbonates
  • Analyse isotopique ; Atlantique ; Atlantique Sud ; Carbone 13 ; Datation C14 ; Déglaciation ; Foraminifère ; Géographie physique ; Milieu marin ; Nannofossile ; Oxygène 18 ; Paléo-environnement ; Quaternaire ; Stratigraphie ; Taxonomie
  • Modélisation numérique des changements globaux. Bilans du 71e congrès annuel de la Société américaine de météorologie, Nouvelle-Orléans, 13-18 janvier 1991)
  • Čislennoe modelirovanie global'nyh izmenenij (k itogam 71-go ežegodnogo sezda Amerikanskogo meteorologičeskogo obščestva, Novyj Orlean, 13-18 janvarja 1991 g.)
  • Atmosphère ; Changement global ; Climatologie ; Dioxyde de carbone ; Hémisphère Nord ; Modèle numérique ; Méthodologie ; Ozone ; Stratosphère ; Variation climatique
  • Atmosphere ; Carbon dioxide ; Climatic variation ; Climatology ; Global change ; Methodology ; Northern hemisphere ; Numerical model ; Ozone ; Stratosphere
  • Effect of cactus pear cultivation after Mediterranean maquis on soil carbon stock, δ13C spatial distribution and root turnover
  • Carbone ; Carbone 13 ; Domaine méditerranéen ; Ecosystème ; Italie ; Maquis ; Matière organique ; Propriétés du sol ; Sicilia ; Sol cultivé ; Utilisation du sol ; Verger
  • Carbon ; Carbon 13 ; Cultivated land ; Ecosystem ; Italy ; Land use ; Mediterranean area ; Mediterranean scrub vegetation ; Orchard ; Organic materials ; Sicilia ; Soil properties
  • The aim of this work was to investigate the effect of land use change from maquis to agriculture on soil organic carbon (SOC) stock and its spatial distribution in a Mediterranean system. Three Mediterranean land use systems (seminatural vegetation