22 research outputs found
Land use change from the sugar cane expansion in the western region of São Paulo state, Brazil
A demanda por alternativas energéticas tem aumentando a produção mundial de biocombustÃveis e, consequentemente, o cultivo das culturas agrÃcolas. No Brasil, o lançamento dos veÃculos bicombustÃveis propiciou a retomada da importância da produção de etanol e, consequentemente, numa nova fase de expansão do cultivo de cana-de-açúcar. Diversas questões relacionadas à sustentabilidade da produção de biocombustÃveis têm sido discutidas na literatura, tais como o efeito na produção de alimentos e na segurança alimentar, o impacto ambiental da mudança do uso da terra e os efeitos sociais no campo. Este trabalho pretende analisar as mudanças no uso da terra na região Oeste Paulista, provocadas pela expansão do cultivo da cana-de-açúcar. Na última década (2003 a 2012), a região Oeste Paulista representou mais da metade da expansão dessa cultura no estado de São Paulo, maior estado produtor brasileiro. O método utilizado foi o Modelo Shift-Share, que, por meio da decomposição da variação das áreas, possibilitou calcular os efeitos escala e substituição das principais atividades em análise. Este trabalho revela que a expansão da cultura da cana-de-açúcar na região estudada ocorreu predominantemente pela substituição de áreas de pastagem e, consequentemente, da atividade pecuária.
[The demand for energy alternatives to oil are increasing global biofuel production and, consequently, the biofuel crops cultivation. In Brazil, the emergence of flex-fuel vehicles resumed the importance of ethanol production, resulting in a new phase of Brazilian sugar cane crop expansion. Several issues related to the sustainability of biofuel production have been discussed in the literature, such as the effect on food production and food security, the environmental impact of land use change and social effects in the field. This study aims to analyze the land use change in the Oeste Paulista region, caused by the expansion of sugar cane cultivation. Between 2003 and 2012, the Oeste Paulista region represented more than half of the expansion of this crop in São Paulo state, the largest producer in Brazil. This paper used the Shift-Share model to decompose the agricultural areas variation and to calculate the replacement of the main activities analyzed. The results revealed that, in the analyzed region, the expansion of sugar cane area has occurred predominantly by replacing pasture and, consequently, by cattle activity.
Testing Luminescence Dating Methods for Small Samples from Very Young Fluvial Deposits
The impetus behind this study is to understand the sedimentological dynamics of very young fluvial systems in the Amazon River catchment and relate these to land use change and modern analogue studies of tidal rhythmites in the geologic record. Initial quartz optically stimulated luminescence (OSL) dating feasibility studies have concentrated on spit and bar deposits in the Rio Tapajós. Many of these features have an appearance of freshly deposited pristine sand, and these observations and information from anecdotal evidence and LandSat imagery suggest an apparent decadal stability. The characteristics of OSL from small (~5 cm) sub-samples from ~65 cm by ~2 cm diameter vertical cores are quite remarkable. Signals from medium-sized aliquots (5 mm diameter) exhibit very high specific luminescence sensitivity, have excellent dose recovery and recycling, essentially independent of preheat, and show minimal heat transfer even at the highest preheats. These characteristics enable measurement of very small signals with reasonable precision and, using modified single-aliquot regenerative-dose (SAR) approaches, equivalent doses as low as ~4 mGy can be obtained. Significant recuperation is observed for samples from two of the study sites and, in these instances, either the acceptance threshold was increased or growth curves were forced through the origin; recuperation is considered most likely to be a measurement artefact given the very small size of natural signals. Dose rates calculated from combined inductively coupled plasma mass spectrometry/inductively coupled plasma optical emission spectrometry (ICP-MS/ICP-OES) and high-resolution gamma spectrometry range from ~0.3 to 0.5 mGya−1 , and OSL ages for features so far investigated range from 13 to 34 years to several 100 years. Sampled sands are rich in quartz and yields of 212–250 µm or 250–310 µm grains indicate high-resolution sampling at 1–2 cm intervals is possible. Despite the use of medium-sized aliquots to ensure the recovery of very dim natural OSL signals, these results demonstrate the potential of OSL for studying very young active fluvial processes in these settings
Examining the relationship between vertical coordination strategies and technical efficiency: Evidence from the Brazilian ethanol industry
The sugarcane industry in Brazil, one of the world's leading producers of ethanol and sugar, is undergoing significant changes driven by geographic expansion and technological innovations. These changes are forcing sugarcane producers and processors, to re-evaluate their vertical coordination and growth strategies. This paper presents an empirical analysis of the relationship between the vertical coordination strategies at the production-processing interface of the Brazilian ethanol supply chain and the technical efficiency of the mills. It utilizes data envelopment analysis and a Tobit censored model in combination with unique data on 204 mills that account for around half of Brazil's sugar and ethanol production. Results indicate that vertical integration and the location of the mill have a statistically significant impact on efficiency. The findings show that the technical efficiency is not the main driver of vertical integration implying that such decisions are primarily motivated by strategic considerations. The mills are likely to forgo gains in technical efficiency in exchange for improving their strategic position through vertical integration. These findings shed light on the underlying motivation for the observed level of vertical integration that accompanies the expansion of the Brazilian sugarcane industry. [EconLit citations: L22, Q12, Q16]
Factors affecting farmers’ willingness to grow alternative biofuel feedstocks across Kansas
Energy conservation has emerged as one of the biggest challenges of the world in the XXI century, and not different from many countries, the US has created plans and policies to stimulate renewable energy alternative. Among the important alternatives for energy conservation is the use of biomass energy. Despite these stimuli production predictions are not confident that production would achieve the planned target for the U.S. Consequently, the predictions raise questions about farmer's willingness to grow bioenergy crops or produce alternative cellulosic feedstocks. In other words, farmers and landholders may not be willing to grow bioenergy crops. With this concerns in mind, the study advances previous research about bioenergy production by evaluating farmer's and landholder's willingness to produce different varieties of biofuel feedstocks. To achieve our goals, we used a mail survey of Kansas farmers conducted from January to April of 2011. The survey contained questions related to how farmers make their land-use decisions covering a wide array of topics. Through this survey, we evaluate the effect of farm characteristics, farm management practices, farmer perceptions (such as risk aversion), physical variables (such as soil, weather, and the availability of water for irrigation) on farmers' willingness to produce value-added feedstocks (e.g., corn stover), dedicated annual bioenergy crops (e.g., energy sorghum), and dedicated perennial bioenergy crops (e.g., switchgrass) for biofuel production in Kansas, though the use of logistic regressions and marginal effects
Spatial–Temporal Analysis of Land Cover Change at the Bento Rodrigues Dam Disaster Area Using Machine Learning Techniques
Disasters are an unpredictable way to change land use and land cover. Improving the accuracy of mapping a disaster area at different time is an essential step to analyze the relationship between human activity and environment. The goals of this study were to test the performance of different processing procedures and examine the effect of adding normalized difference vegetation index (NDVI) as an additional classification feature for mapping land cover changes due to a disaster. Using Landsat ETM+ and OLI images of the Bento Rodrigues mine tailing disaster area, we created two datasets, one with six bands, and the other one with six bands plus the NDVI. We used support vector machine (SVM) and decision tree (DT) algorithms to build classifier models and validated models performance using 10-fold cross-validation, resulting in accuracies higher than 90%. The processed results indicated that the accuracy could reach or exceed 80%, and the support vector machine had a better performance than the decision tree. We also calculated each land cover type’s sensitivity (true positive rate) and found that Agriculture, Forest and Mine sites had higher values but Bareland and Water had lower values. Then, we visualized land cover maps in 2000 and 2017 and found out the Mine sites areas have been expanded about twice of the size, but Forest decreased 12.43%. Our findings showed that it is feasible to create a training data pool and use machine learning algorithms to classify a different year’s Landsat products and NDVI can improve the vegetation covered land classification. Furthermore, this approach can provide a venue to analyze land pattern change in a disaster area over time
It’s all about location?: An analysis of the factors that affect the location decision of sugarcane processing mills in Goiás and Mato Grosso do Sul, Brazil
Unofficial Road Building in the Amazon: Socioeconomic and Biophysical Explanations
Roads have manifold social and environmental impacts, including regional development, social conflicts and habitat fragmentation. 'Road ecology' has emerged as an approach to evaluate the various ecological and hydrological impacts of roads. This article aims to complement road ecology by examining the socio-spatial processes of road building itself. Focusing on the Brazilian Amazon, a heavily-studied context due to forest fragmentation by roads, the authors consider non-state social actors who build 'unofficial roads' for the purpose of gaining access to natural resources to support livelihoods and community development. They examine four case studies of roads with distinct histories in order to explain the socio-spatial processes behind road building in terms of profit maximization, land tenure claims, co-operative and conflictive political ecologies, and constraints as well as opportunities afforded by the biophysical environment. The study cases illustrate the need for a multi-pronged theoretical approach to understanding road building, and call for more attention to the role of non-state actors in unofficial road construction
Spatial–Temporal Analysis of Land Cover Change at the Bento Rodrigues Dam Disaster Area Using Machine Learning Techniques
Trust me! Examining the contractual relationships between sugarcane producers and mills in the Cerrado
An increase in biofuel demand aligned with public policies has fueled the expansion of sugarcane into Goiás and Mato Grosso do Sul in the Cerrado. Geographic, temporal and physical asset specificities delimit the area from which mills can procure sugarcane, making sugarcane producers and mills dependent on each other. Thus contracting is a common practice in sugarcane production in the Cerrado and its success directly impacts the sustainability of the ethanol expansion. We fill a gap in the literature on producers’ contract acceptance and trust by determining the factors that affect contract perception and trust with contractors. Using primary data from the states of Goiás and Mato Grosso do Sul we estimate ordered logit models using producer’s perceptions, their characteristics and that of their enterprise. Profits and experience are important factors for a producer when considering a contract. Communication, transparency and other farmer’s perception of a mill were important in building trust. Mills wanting to improve their chances of signing a contract should focus on more participation in the community and on better communication with farmers.O aumento na demanda por biocombustÃveis aliado à s polÃticas públicas têm promovido a expansão da cana no Cerrado, especialmente em Goiás e Mato Grosso do Sul. As especificidades geográficas, temporais e fÃsicas dos ativos limita a área de onde advem a cana, tornando usinas e produtores dependents uns nos outros. Com isso, contratos são uma prática comum no setor sucroalcoleiro e seu sucesso tem consequências diretas para a sustentabilidade da expansão da cana no Cerrado. Preenchemos, neste estudo, a lacuna na literatura sobre a aceitação de contratos e confiança, determinando os fatores que alteram a percepção do produtor quanto ao contrato e quanto à confiança na usina. Usando dados primários de Goiás e Mato Grosso do Sul estimamos modelos logit ordenados usando as percepções e caracterÃsticas dos produtores e de seus estabelecimentos. Lucro e tradição foram identificados como importantes para a aceitação de um contrato. Comunicação, transparência e a opinião demais produtores foram importantes fatores no desenvolvimento de confiança na usina. Logo, usinas que querem melhorar suas a aceitação de seus contratos devem se esforçar em participar mais na comunidade local e na melhoria da comunicação com os fazendeiros
Ethanol and sugarcane expansion in Brazil: what is fueling the ethanol industry?
This case study describes Brazilian ethanol industry and strategic issues faced by sugarcane farmers and processors as a result of recent industry expansion into the states of Goias and Mato Grosso do Sul. It provides detailed description of the ethanol supply chain in Brazil from field to market and discusses market drivers influencing the industry. Shaped by government regulations, market liberalization, globalization, and technological change, the Brazilian ethanol industry provides a rich context for learning and applying strategic analysis tools. The case is designed to be used in a graduate or undergraduate agribusiness management or strategic management course. The specific teaching objective for this case is to refine and reinforce students’ understanding of industry analysis and the effect of market drivers on competitive forces in an industry. Students will be expected to conduct an industry analysis and provide strategy recommendations to managers of ethanol plants and farmers. The case study incorporates all of the essential information for students to understand the underlying economics of the ethanol value chain and how the external forces shape strategic growth opportunities