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Measurements of the organic carbon inventory, its stable isotopic composition and radiocarbon content were used to deduce vegetation history from two soil profiles in arboreal and grassy savanna ecotones in the Brazilian Pantanal. The Pantanal is a large floodplain area with grass-dominated lowlands subject to seasonal flooding, and arboreal savanna uplands which are only rarely flooded. Organic carbon inventories were lower in the grassy savanna site than in the upland arboreal savanna site, with carbon decreasing exponentially with depth from the surface in both profiles. Changes in ^^C of soil organic matter (SOM) with depth differed markedly between the two sites. Differences in surface SOM "C values reflect the change from C3 to C4 plants between the sites, as confirmed by measurements of '^C of vegetation and the soil surface along a transect between the upland closed-canopy forest and lowland grassy savanna. Changes of ^^C in SOM with depth at both sites are larger than the 3-4 per mil increases expected from fractionation associated with organic matter decomposition. We interpret these as recording past changes in the relative abundance of C3 and C4 plants at these sites. Mass balances with ^'*C and "C suggest that past vegetational changes from C3 to C4 plants in the grassy savanna, and in the deeper part of the arboreal savanna, occurred between 4600 and 11 400 BP, when major climatic changes were also observed in several places of the South American Continent. The change from C4 to C3, observed only in the upper part of the arboreal savanna, was much more recent (1400 BP), and was probably caused by a local change in the flooding regime.

Recent debate about agricultural greenhouse gases (GHG) emissions mitigation highlights tradeoffs inherent in the way we produce and consume food, with increasing scrutiny on emissionsintensive livestock products 1-3. While most research has focussed on mitigation through improved productivity 4,5 , systemic interactions resulting from reduced beef production at regional level are still unexplored. A detailed optimisation model of beef production encompassing pasture degradation and recovery processes, animal and deforestation emissions, soil organic carbon (SOC) dynamics and upstream lifecycle inventory was developed and parameterized for the Brazilian Cerrado. Economic return was maximized considering two alternative scenarios: Decoupled Livestock Deforestation (DLD), assuming baseline deforestation rates controlled by effective policy; and Coupled Livestock Deforestation (CLD), where shifting beef demand alters deforestation rates. In DLD, reduced consumption actually leads to less productive beef systems, associated with higher emissions intensities and total emissions, while increased production leads to more efficient systems with boosted SOC stocks, reducing both per kg and total emissions. Under CLD, increased production leads to 60% higher emissions than in DLD. The results indicate the extent to which deforestation control contributes to sustainable intensification in Cerrado beef systems, and how alternative life-cycle analytical approaches 6 result in significantly different emission estimates.

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RESUMOA composição isotópica do carbono (δ 13 C) foi utilizada na determinação da origem botânica (C3 x C4) de amostras de café, vinho, cerveja e vodka, de diferentes marcas e procedências, comercializadas no Brasil. Dentre as marcas de café analisadas, apenas uma apresentou um elevado percentual de plantas C4 em sua composição, evidenciado pelo valor de δ 13 C (-16,2). Os valores de δ 13 C das amostras de vinhos brasileiros, variaram entre -25,1 e -17,1, indicando a presença de carbono de origem C4 nas amostras que tiveram os maiores valores de δ 13 C. Duas marcas de vinhos importados, por sua vez, apresentaram δ 13 C característico de planta C3 (-27,1 e -26,3). Os valores de δ 13 C das vodkas importadas variaram entre -26,4 e -23,9, e as brasileiras entre -12,8 e -11,8, excetuando-se uma marca que apresentou valor -23,1. As marcas de cervejas importadas, em sua maioria, apresentaram valores mais negativos (-27,3 a -20,7) que as nacionais (-25,9 a -18,4). Estes resultados evidenciam a eficiência desta metodologia na determinação da origem do C e percentual de mistura destas bebidas. Palavras-chave: isótopo estável; carbono; café; vinho; vodka; cerveja. SUMMARYSTABLE ISOTOPES AND BEVERAGE PRODUCTION: WHERE DOES THE CARBON WE DRINK COME FROM? We used the carbon isotopic composition (δ 13 C) to determine the botanical origin (whether C3 or C4) of coffee, wine, beer and vodka samples from different brands and origins commercialized in Brazil. Only one coffee sample showed a δ 13 C typical of a mixture with C4 plants (δ 13 C -16.2). The Brazilian wine samples varied from δ 13 C -25.1 to -18.6, indicating the presence of carbon from C4 plants in samples with greater values, while the imported wine showed δ 13 C characteristic of C3 plants (-27.1 and -26.3). Imported vodka also showed δ 13 C typical of C3 plants (-26.4 and -23.9), while Brazilian counterparts were typically made from C4 plants (-12.8 to -11.8), except for one sample (23,1). Most of the imported beers showed more negative δ 13 C (-27.3 to -20.7) than did the Brazilian beers (-25.9 to -18.4). These results demonstrate the methods efficiency for tracing the carbon origin and determining the extent of blending in beverages.

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Foram avaliados o desempenho e componentes do peso vivo e da carcaça de ovinos machos castrados, em confinamento por um período de 80 dias, antes do abate aos 12 meses de idade, alimentados com uma dieta composta por silagem de milho (60,50% da MS) + concentrado (39,50% da MS), contendo 17,13% de PB. Foram comparados os seguintes genótipos: Hampshire Down (H D), Téxel (T), Corriedale (C), cruza Suffolk x Corriedale (SC) e cruza lle de France x Corriedale (IC). O H D apresentou consumo de MS (g/an/dia) similar ao SC e superior ao IC, C e T (P < 0,0013), que foram similares entre si (P ≥ 0,05). Quando o consumo de MS foi expresso em kg/100 kg de PV, o T foi similar ao HD e C e inferior (P < 0,0093) ao SC e IC, que foram similares (P ≥ 0,05) entre si. Quando este foi expresso em g/UTM/dia não houve diferença (P ≥ 0,05) entre os genótipos. Os ganhos de peso médio diário apresentados pelo SC e HD foram similares (P ≥ 0,05) ao IC e superiores (P < 0,0022) ao T e C que foram similares (P ≥ 0,05) entre si. Com relação a conversão de MS em ganho de peso, não houve diferença estatística (P ≥ 0,05) entre os genótipos. O rendimento de carcaça quente foi maior (P < 0,0001) no H D enquanto nos demais genótipos foram similares (P ≥ 0,05) entre si. Os genótipos C e CS apresentaram maior (P < 0,0174) percentual de cabeça enquanto o menor percentual foi apresentado pelo H D, sendo que nos demais foi similar (P ≥ 0,05). Por outro lado, o maior (P < 0,0004) percentual de patas foi apresentado pelo IC e o menor pelo HD, enquanto nos demais genótipos foi similar (P ≥ 0,05). Já o percentual de pele foi superior (P < 0,0004) no C, inferior no H D e similar (P ≥ 0,05) nos demais genótipos. No percentual de trato digestivo + vísceras + perda de sangue não houve diferença estatística (P ≥ 0,05) entre os genótipos.

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