Organic matter and natural carbon-13 distribution in forested and cultivated oxisols

Etude de la distribution du carbone et de 13C et de leur variation suite au développement des cultures dans trois oxisols de la région de Piracicaba (Sao Paulo, Brésil

d13C pattern of dissolved inorganic carbon in a small granitic catchment: the Strengbach case study (Vosges mountains, France)

The transfers and origins of dissolved inorganic carbon DIC. were studied for a year in a soil–spring–stream system in the Strengbach catchment, Vosges mountains, France. This 80 ha experimental research basin is located on the eastern side of the mountains, at an altitude ranging from 883 to 1146 m.a.s.l. and is mainly covered by spruce 80%.. Brown acid and podzolic soils developed on a granitic basement, and, as a result, the DIC originates solely from CO2 generated by oxidation of soil organic matter. The d13CDIC. in catchment waters is highly variable, from about y22‰ in the springs and piezometers to about y12‰ in the stream at the outlet of the catchment. In the springs, pronounced seasonal variations of d13C exist, with the DIC in isotopic equilibrium with the soil CO that has estimated d13DIC 2 C of about y24‰ in winter and y20‰ in summer. These seasonal variations reflect an isotopic fractionation that seems only induced by molecular diffusion of soil CO2 in summer. In stream water, seasonal variations are small and the relatively heavy DIC y12‰ on average. is a result of isotopic equilibration of the aqueous CO2 with atmospheric CO2

Spatial analysis of within-vineyard grapevine sensitivity to solar irradiance patterns. A case study using Pinot noir in a complex terrain

Communication orale, texte intégralWe analyze how the patterns of the solar irradiance affect the growth of Pinot noir grapevines at stand-scale over a hilly terrain bounded by a coniferous forest. Results show that the patterns of irradiance deficit are the primary driving force of the growth. Linear trends display good correlation between the total deficit of irradiance, and the developed growth index (R2 up to 0.96 ). This result also suggests the impact of low minimum temperature due to cold air drainage and stagnation. Results lead to propose a model able to capture at stand-scale 90% of the whole spatial variability of the growth. The model accounts for the diffuse component of the deficit of irradiance and the squared temperature anomalies. Combining such models through the use of GIS enables to better understand the driving mechanisms of grapevine growth over complex terrain, towards a better management of the “terroir” potential whithin climate change

Hydroclimatology and biogeochemistry of the Amazon 1. Erosion

The Amazon is the largest stream in the world. Its basin covers at least 7. lo6 km2, which represents - 5% of the global continental area and almost 70% of the area of the continents localized in the equatorial zone, between 5"s and 5"N of latitude. The global tropical moist forest covers -9.35. lo6 km2, so that the Brazilian evergreen rain forest represents at least 50% of this area. At Obidos, the most accessible downstream station for collecting data, the area concerned is 4.619- lo6 km2. The purpose of these two extended abstracts is to show how changes and oscillations of climate can significantly affect erosion as well as carbon and nitrogen cycles, and may also mask the degradations of the environment due to deforestation

LES MECANISMES DE PRODUCTION D'OXYDES D'AZOTE GAZEUX (N2O ET NO) PAR LES SOLS EN CONDITIONS AEREES

DIJON-BU Sciences Economie (212312102) / SudocSudocFranceF

Effets à long terme de l'apport répété de déchets organiques sur l'évolution de la matière organique et des éléments traces métalliques dans un sol sableux acide (Couhins, 33)

DIJON-BU Sciences Economie (212312102) / SudocSudocFranceF

LE CARBONE ORGANIQUE DES SOLS DES LANDES DE GASCOGNE VARIABILITE SPATIALE ET EFFETS DES PRATIQUES SYLVICOLES ET AGRICOLES

DIJON-BU Sciences Economie (212312102) / SudocSudocFranceF

Dynamique du transfert vertical d'herbicides en sols viticoles calcaires (approche à l'aide de colonnes de sol)

DIJON-BU Sciences Economie (212312102) / SudocSudocFranceF

Impact d'une coupe rase sur les teneurs en carbone organique et leur dynamique dans les sols des Landes de Gascogne

National audienc

Transfert du diuron et de l'oryzalin en lysimètres dans trois sols viticoles non perturbés (Vosne-Romanée, 21)

National audienc