Search

Body size influences the effect of individuals and assemblages on ecosystem functioning and defines how they respond to ecosystem changes. We evaluated how body size structure of fish assemblages and functional groups respond to human modifications at catchment, riparian and local scales in 40 streams of the Pampa grasslands, southern Brazil. To describe body size structure, we calculated the mean, coefficient of variation, skewness, and kurtosis, using individual biomass data for the entire fish assemblages and separately by functional group. The results suggested that body size response depends on body size metrics, functional group, and the spatial scale of land use. From 11 functional groups, only five showed a clear response to land use. In general, most functional groups had a higher concentration of small sizes (left-skewed) in response to increased land use measured at distinct spatial scales (local, riparian, and catchment), and a greater concentration of sizes in a narrow and central distribution (higher kurtosis). However, the responses were complex and varied between the functional groups. We conclude that considering ecomorphological and trophic features separately by functional group and assessing multiple body size metrics contributed greatly to detecting the influence of land use on fish body size. [ABSTRACT FROM AUTHOR]

Abstract: The paper discusses the availability of biomass in Brazil to supply charcoal to the steel industry on the bases of an initial global assessment of land potentially available for plantations and of Brazilian data that allows refining the assessment and specifying the issue of practical availability. Technical potentials are first assessed through a series of simple rules against direct competition with agriculture, forests and protected areas, and of quantitative criteria, whether geo-climatic (rainfall), demographic (population density) or legal (reserves). Institutional, social and economic factors are then identified and discussed so as to account for the practical availability of Brazilian biomass through six criteria. The ranking of nine Brazilian States according to these criteria brings out the necessary trade-offs in the selection of land for plantations that would efficiently supply charcoal to the steel industry. [Copyright &y& Elsevier]

Biofuels are predicted to constitute a large proportion of fuel consumption in the global transport sector under stringent climate mitigation polices in future. In Brazil, sugarcane ethanol has been widely deployed at large scale and an oriented expansion of sugarcane is considered to be a key measure to ensure the expected positive outcomes from biofuels. In this study, more recent and accurate georeferenced information were combined with an enhanced land use classification system to update the original Sugarcane Agroecological Zoning (SAEZ). We also excluded environmentally relevant areas (ERA) in our updated SAEZ to create a new set of reference maps for supporting future prioritization of areas for sugarcane ethanol expansion. We mapped 41.7 Mha as suitable land for sugarcane expansion in center-south region of Brazil, differently from the 50 Mha indicated in the original SAEZ. After excluding the ERA, 33.7 Mha was found to be suitable for sugarcane expansion, of which 20 Mha is currently occupied with pasture lands. About half of these areas were located in Mato Grosso do Sul and Minas Gerais states and an exploratory assessment of two microregions from these states demonstrated the importance of conducting regional assessments to prioritize the areas for a more sustainable sugarcane expansion to meet future bioenergy demands. • Our analysis identified an area 17% smaller than original agro-ecological zoning suitable for sugarcane expansion. • By excluding environmentally relevant areas, the total suitable area for sugarcane expansion is reduced to 33.7 Mha. • About two thirds of that area is currently occupied with pasture lands. • About half of suitable areas occupied with pasture lands are in two Brazilian states. • Local conditions are fundamental for oriented expansion of bioenergy production. [ABSTRACT FROM AUTHOR]