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In this paper, we describe poisoning outbreaks of Xanthium strumarium in cattle on the borders of the Araguari River, Southeastern Brazil. In this region, several hydroelectric plants promote transient flooding, which creates a favorable environment for the invasion of X. strumarium in extensive areas, often as the predominant species in those areas. The outbreaks occurred between July and September (dry season). Bovines of all ages were affected, including suckling animals. Mortality varied from 2% to 5.5%. The animals exhibited ataxia, weakness, loss of balance, recumbency, and the majority were found dead. Laboratory results showed a marked increase in the serum activities of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and gamma-glutamyltransferase. Histological and ultrastructural changes in the liver consisted of centrilobular necrosis and hemorrhage. On toxicological evaluation, the dicotyledons contained 0.30 μg/mg of atractyloside and 0.37 μg/mg of carboxyatractyloside. Considerable economic loss has occurred in this region due to the lack of knowledge regarding X. strumarium as a toxic plant and its adaptation to the environmental and climatic conditions of the region, which have made the condition endemic. • Xanthium strumarium , which contains carboxyatractyloside, is a cause of hepatic liver necrosis in ruminants and horses. • The poisoning has been reported sporadically in temperate areas due to the ingestion of the seedling or the burs of the plant. • The poisoning became very important after the introduction of the plant where hydroelectric plants promote transient flooding. • The seedlings sprout after flooding, during the dry period, when the water returns to its normal level. • To prevent severe losses, it is important to reduce the infestation of X. strumarium in such areas. [ABSTRACT FROM AUTHOR]

• The environmental efficiency of pasture-based dairy farming is assessed. • Farmers can increase their environmental efficiency, producing more milk and less methane. • The abatement cost per tonne of methane was US $2,254. • GHG policy should take a precautionary approach regarding food security and nutrition. Increasing dairy farm productivity while simultaneously mitigating greenhouse gases emissions is a common policy goal in many countries. In this paper, we assess trade-offs and synergies between these goals for pasture-based dairy farms in Brazil. We apply stochastic frontier analysis within a translog hyperbolic distance function specification, including methane emissions as an undesirable output and accounting for annual climatic types. Our results indicate that on average, farmers can improve their production by 9.4% while simultaneously reducing methane emissions by 8.7%. The adoption of more productive cows and improved pastures have a positive effect on the environmental efficiency of the farms. Farmers operating in warmer and dryer climate types tend to have lower environmental efficiency. Calculating shadow prices for methane emitted on farms indicates that the mean abatement costs of methane are US $2,254 per tonne. Overall, by reducing inefficiency, dairy farmers can significantly increase farm production while simultaneously reducing emissions and thus contribute to national commitments to eradicate hunger and mitigate methane emissions. [ABSTRACT FROM AUTHOR]

Technology selection, its power and efficiency determination for electricity generation using agroforestry residues is the main goal and the novelty of this paper. It is based on the fitted efficiency vs. power curves for commercial mature technologies. The assessment of the level of maturity of biomass-based electricity generation Technologies based on Technology Readiness Levels was used as criteria to define the technologies to be considered in this study: conventional Rankine cycle, organic Rankine cycle and gasifier/internal combustion engine. Pretreatment technologies influence on generation costs is determined based on chippers and drum dryers cost and its energy consumption. We developed a coherent methodology for selecting the technology and calculation of power/efficiency of electricity generation projects considering biomass derived from plant-based lignocellulosic solid biomass residues derived from agricultural and forest activities. A case study based on eucalyptus forest residues availability in three microregions of the Minas Gerais State in Brazil allowed to define the technology to be used in each case and its power, efficiency and levelized cost of electricity, that includes pretreatment and logistic costs. Obtained LCOE values are compared with data from different publications, that is a validation of the presented methodology. Results allow concluding about the considerable influence of residues logistics on LCOE. [Display omitted] • Lowest LCOE corresponds to CRC:0,1652 USD/kWh. • Highest LCOE corresponds to G/ICE with 0,3080 USD/kWh. • Costs and power consumption data of pretreatment technologies are presented. • Fitted power-efficiency curves based on an extensive literature review are presented. • Only technologies with higher maturity, CRC, ORC and G/ICE, are considered. [ABSTRACT FROM AUTHOR]

The objective of this paper was to establish disaggregation coefficients for the state of Minas Gerais, Brazil, under the premises of i) stationarity of the disaggregation coefficients according to the return period and ii) spatial validation of the disaggregation coefficients. The regression analysis was used as a statistical procedure to verify the significance of the coefficients of disaggregation slope coefficient as a function of return period in daily and sub-daily rainfall time series in rain gauges distributed throughout the state of Minas Gerais. Most of the disaggregation coefficients (94% of the situations) did not show a tendency to change due to the return period. The detected trends modified coefficients of disaggregation by up to 21% to the average obtained for different return periods. It was also verified that there is a significant difference between rainfall ratios of different durations, for different locations, indicating that the coefficients of disaggregation are not regional, but rather local. The use of disaggregation coefficients to obtain sub-daily rainfall is possible, provided that the representative coefficients of the locality are used. In this context, the spatialization of disaggregation coefficients is an important approach. • Relations between rainfall of different durations are disaggregation coefficients. • The use of disaggregation coefficients to obtain sub-daily rainfall is possible. • Disaggregation coefficients did not show a trend to change due to return period. • The disaggregation coefficients have local validity. • The spatialization technique can favor suitable disaggregation coefficients. [ABSTRACT FROM AUTHOR]

• The vereda's Histosol began its genesis in the late Pleistocene. • A multivariate approach enables identifying four main genesis processes/drivers. • Five phases of changes in the environment could be verified. • Veredas ' deep soils are important records of past changes. • Soil properties of veredas are potencial proxies of paleoenvironmental changes. The peat properties of Brazilian palm swamps, or veredas, as they are locally known, lend these environments the character of water reservoirs and carbon stores, in addition to being important archives of past changes. In this paper, we present, in high-resolution, the stratigraphy and morphological, physical, chemical, elemental, and isotopic properties of a deep soil vereda core (Pau Grande, with 283 cm) from the Grande Sertão Veredas National Park, in the state of Minas Gerais, Brazil. The core is constituted by 10 histic horizons in the first 151 cm, and one mineral layer from 151 to 283 cm. Peat sedimentation rates were different along its depth, as follow: 0.0273 cm year−1 (109–111 cm), 0.0018 cm year−1 (85–87 cm), 0.0027 cm year−1 (59–61 cm), 0.0031 cm year−1 (45–47 cm), and 0.0042 cm year−1 (24–26 cm). Mean values of the main peat properties were: 16% for C, 44% for Si, −17.20‰ for δ13C, 3.68‰ for δ15N, 167% for gravimetric moisture, 75% for mineral material, 8% for rubbed fibres, 3.58 for pH, 0.77 Mg m−3 for bulk density, and 0.15 for bulk density of the organic matter. Principal components analysis was applied to peat properties to assist in the identification of processes/drivers that control the nature of the studied vereda , in addition to providing evidence of changes in the paleoenvironment. The first principal component, PC1, is related to the relative accumulation of organic versus local mineral matter, linked to the evolution of the catchment soils (erosion) and possible associated vegetation (C3 and C4 plants); PC2 is related to the hydromorphism conditions; PC3 is related to the incorporation of inorganic material through the deposition of dust from regional sources; and PC4 is related to the main sources of organic matter. Radiocarbon dating indicates this vereda began its formation during the late Pleistocene. Five phases of changes in the environment were also verified: I) 33,309–26,818 cal BP – formation of a lake or a shallow water body, predominance of algae, and locally and regionally unstable environment; II) 26,818–16,659 cal BP – predominance of terrestrial plants, locally stable but regionally unstable environment; III) 16,659–10,401 cal BP – oxic, drier environment with a predominance of C4 terrestrial plants, and a simultaneous increase in local instability with stabilization of the regional environment at ∼ 15.0 kyr cal BP; IV) 10,401–5,052 cal BP – return to being an algal source in even more oxic conditions, and beginning of greater stability in both the local and regional environments; and V) 5,052 cal BP until present – consolidation of the stable environment initiated in the previous phase, characteristic reducing environment to that currently found in the Pau Grande vereda , and changing the contribution of organic matter sources, initially with terrestrial plants and, subsequently, algae. Our results suggest that the Pau Grande vereda is a complex ecosystem. These environments have a large potential for studies on environmental reconstruction and climate changes that have occurred since the late Pleistocene, and they should be fully protected. [ABSTRACT FROM AUTHOR]

• This study shows the technical and economic viability of CAES using Ethanol. • The CAES system was planned to be implemented in abandoned mines. • Geological characteristics, wind speed and thermodynamic aspects was analysed. This paper shows the results of a study that sought to verify the technical and economic viability of implanting a Compressed Air Energy Storage (CAES) energy system that operated connected to a wind farm, in such a way as to guarantee supply even in parts of the day with low wind intensity. Because this study sought implement this system in a state located in the inland of Brazil where there were no mining caverns capable of storing the compressed air, we opted for using abandoned mines that could serve this function. However, it was difficult to find a location with an abandoned mine for storing compressed air, and a location with good air flow for energy generation, and so the endeavor was ultimately economically unviable. This study shows the geological characteristics of the state, the locations of the main wind flow areas, and the thermodynamic and energy calculations required for sizing and specifying the components for the project and gives an economic analysis of the endeavor. Contrary to initial hypothesis, it was not found any favorable sites in the state of Minas Gerais fort storing compressed air generated from wind energy. Furthermore, the cost analysis showed that this type of endeavor needs policies to gain scale. [ABSTRACT FROM AUTHOR]