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Land use is a driver for hydrological and soil erosion responses at the watershed scale. This study aimed to assess the hydrological and soil erosion processes in small watersheds under three different land uses, at three time scales. We investigated four small watersheds in southern Brazil: Agricultural North watershed (ANW), Agricultural South watershed (ASW), Eucalyptus watershed (EW), and Grassland watershed (GW). The SWAT (Soil and Water Assessment Tool) model was used to simulate streamflow (SF) and sediment yield (SY) at monthly, daily and hourly time scales. EW had the lowest SF and SY, whereas ANW showed the highest SY with an increase of 90% and ASW had the highest SF with an increase of 70%. The SWAT model had a satisfactory performance in all time scales and watersheds for SF and SY (NSE and R2 ≥ 0.3 and Pbias ≤ ± 39%). Overall, land use has a major impact on hydrological and soil erosion responses, and the magnitude of these processes depends on the time scale. [ABSTRACT FROM AUTHOR]

This work performs an analysis of the spatial pattern of the coffee harvested area in the Rio de Janeiro state between 1988 and 2018. To relate changes in land cover and land use with the coffee land abandonment, geographically weighted regressions (GWR) were adopted with the rates of change in forest and pasture cover, and also with changes in the size of the cattle herd. The coffee-crop area evolution identifies three behaviors: the concentration of planted area in the northwest, with constant growth after the 1990s; a remaining area in the mountainous region; and the abandonment of coffee farms in the south. Although bivariate models can't explain the changes in land cover and land use, geographically weighted regressions point to a trend of replacing coffee cover with pasturelands in the south region of the state, while eventual changes for forest cover are more likely in other regions. [ABSTRACT FROM AUTHOR]

This study aims to understand the response of the trophic state index (TSI) of a reservoir under different watershed land-use scenarios. A novel methodology was applied to the Verde River Basin in the south of Brazil, which is exploited by agricultural activity and has a reservoir for water supply. An ecohydrological model was used to calculate daily nutrient concentrations in the water system, which allowed the determination of the reservoir's TSI. The authors propose a new TSI known as TSImod, considering phosphorus, nitrogen, and chlorophyll in its determination. The results indicate that TSImod may be more appropriate for classifying highly impacted environments when compared to the index currently used in Brazil. The Verde River Reservoir was classified as mesotrophic under the current land-use scenario and eutrophic under the proposed scenarios. The framework developed in this study can be replicated in other watersheds to evaluate the impacts of land-use change on water quality. [ABSTRACT FROM AUTHOR]

This article deploys the 'Theater of Cruelty,' articulated by the French surrealist Antonin Artaud, as a conceptual heuristic to explicate the empirical world of contemporary Amazonia, in particular the 'South of Para,' a site of land war and forest destruction, which the Theater of Cruelty posits as a single dramatic event. We pursue this explication via direct physical immersion, in the form of a travelogue following State Road PA-150 from Maraba to Eldorado dos Carajas, the scene of a massacre of nineteen land reform activists, shot down by Brazilian military police in collusion with the landed elite in 1996. Along the way, we have occasion to encounter the land reform movements and the forces of repression, which we depict both descriptively and theoretically, using our field trip as a point of departure for philosophical elaboration. To this end, we activate Artaud's 'Theater of Cruelty' to disclose the nature of violent conflict in the region. We suggest that theater, more generally, provides structure for cruel performance, and that violent land conflict, together with forest destruction, constitutes a predictable tragedy of theatrical events. In other words, violent land conflict in Amazonia, with all its terrible implications for people and environment, can be grasped as a theatrical structure, with philosophic and material consequences for mind and body. Thus, we articulate the development discourse of Amazonia as a violent, existential game, not a narrative of disembodied forces. [ABSTRACT FROM AUTHOR]

Global energy demand will increase through the twenty-first century. Competition for energy resources has already revealed geopolitical fault lines, and the dependence of industrial economies on fossil fuel promises to keep nations on edge. A widespread consensus has emerged that societies must transition to a new energy basis, given that fossil fuel is nonrenewable and its combustion leads to global warming. Although alternatives like nuclear energy and hydropower provide important electrical supplies locally, the search goes on, and recently much attention has focused on biofuel. Although biofuel represents a renewable and 'green' energy, there is also a downside. This article considers one potential problem, namely, the impact of growing international biofuel demand on Amazonia. The article focuses on Brazil, given the explosive growth of Brazilian agriculture, and notable effects on forests within its national borders. The article seeks to answer this question: How will global demand for Brazil's land-based commodities, including biofuel, impact its tropical forest in the Amazon basin? In attempting to answer this question, the article describes recent agricultural expansion in Brazil and its emergent landscape of renewable energy. Using an adaptation of rent theory, it frames a concept of landscape cascade and shows how Brazil's expanding landscape of renewable energy is impacting forest areas at a great distance. The article then considers recent projections of demand for Amazonian land out to 2020, given growth of Brazilian biofuel production and cattle herds. The projections indicate that more Amazonian land will be demanded than has been made available by Brazilian environmental policy. With this result in mind, the article discusses the discursive dismemberment of Amazonia and how this articulates with efforts by Brazilian politicians to increase the region's land supply. The article points out that agricultural intensification holds the key to meeting global demand without degrading the Amazonian forest, a landscape unique in the world for its ecological and cultural riches. [ABSTRACT FROM AUTHOR]

We examine how access regimes, defined by a set of interrelated institutions and organizations, facilitated the flow of production resources and benefits that resulted in patterns of land change in the Brazilian Cerrado. We analyzed remotely sensed data (Landsat MSS, TM, +ETM) for three time periods (1972/1973-1986, 1986-1992, 1992-2002) with qualitative and archival data for eastern Mato Grosso state. Overall we found that land privately colonized was cleared more rapidly and extensively than lands under no colonization scheme. We also identified significant spatial variability in Cerrado conversion within and outside colonization areas and variability of annual rates of Cerrado conversion during each period. We explain that farmers in the Cerrado engaged in land-leasing and production contracts and worked through cooperatives and firms to marshal resources, including credit, technology, and inputs, which, in turn, influenced land-use decisions and regional patterns of land-cover change. We conclude that a mesoscale analytical framework that examines how land managers access natural and productive resources provides useful insights to explain the processes that cause patterns of high-input agricultural expansion. [ABSTRACT FROM AUTHOR]

The South of Pará, located in the heart of the Brazilian Amazon, has become notorious for violent land struggle. Although land conflict has a long history in Brazil, and today impacts many parts of the country, violence is most severe and persistent here. The purpose of this article is to examine why. Specifically, we consider how a particular Amazonian place, the so-called South of Pará, has come to be known as Brazil's most dangerous badland. We begin by considering the predominant literature, which attributes land conflict to the frontier expansion process with intensified struggle emerging in the face of rising property values and demand for private property associated with capitalist development. From this discussion, we distill a concept of the frontier, based on notions of property rights evolution and locational rents. We then empirically test the persistence of place-based violence in the region, and assess the frontier movement through an analysis of transportation costs. Findings from the analyses indicate that the prevalent theorization of frontier violence in Amazônia does little to explain its persistent and pervasive nature in the South of Pará. To fill this gap in understanding, we develop an explanation based on the geographic conception of place, and we use contentious politics theory heuristically to elucidate the ways in which general processes interact with place-specific history to engender a landscape of violence. In so doing, we focus on environmental, cognitive, and relational mechanisms (and implicated structures), and attempt to deploy them in an explanatory framework that allows direct observation of the accumulating layers of the region's tragic history. We end by placing our discussion within a political ecological context, and consider the implications of the Amazon Land War for the environment. [ABSTRACT FROM AUTHOR]

Tropical deforestation is a significant driver of global environmental change, given its impacts on the carbon cycle and biodiversity. Loss of the Amazon forest, the focus of this article, is of particular concern because of the size and the rapid rate at which the forest is being converted to agricultural use. In this article, we identify what has been the most important driver of deforestation in a specific colonization frontier in the Brazilian Amazon. To this end, we consider (1) the land-use dynamics of smallholder households, (2) the formation of pasture by large-scale ranchers, and (3) structural processes of land aggregation by ranchers. Much has been written about relations between smallholders and ranchers in the Brazilian Amazon, particularly those involving conflict over land, and this article explicates the implications of such social processes for land cover. Toward this end, we draw on panel data (1996-2002) and satellite imagery (1986-1999) to show the deforestation that is attributable to small- and largeholders, and the deforestation that is attributable to aggregations of property arising from a process that we refer to as frontier stratification. Evidently, most of the recent deforestation in the study area has resulted from the household processes of smallholders, not from conversions to pasture pursuant to the appropriations of smallholders' property by well-capitalized ranchers or speculators. [ABSTRACT FROM AUTHOR]

In recent years, scholars of “contentious politics” have paid increasing attention to the dynamics of space and place in the construction of organized resistance. To date, however, the literature has tended to focus on the social construction of space rather than the equally important spatial constitution of the social. In this paper, I analyze how particular understandings of space, or what I call “spatial imaginaries”—cognitive frameworks, both collective and individual, constituted through the lived experiences, perceptions, and conceptions of space itself—influenced the formation of the largest grassroots social movement in Brazilian history, the Movement of Rural Landless Workers (the MST). I analyze the decision to join the MST among small family farmers in southern Brazil and rural plantation workers in northeastern Brazil. People from both groups decided to join the movement, but the farmers from southern Brazil used their spatial imaginaries to embrace the act of occupying land and to create new frontiers for colonization while the rural workers from northeastern Brazil overcame the spatial imaginaries produced through the plantation labor system and joined the movement because they had few other options available to them. Because such imaginaries stay with people long after they engage in the initial acts of mobilization, incorporating this sort of analysis introduces an important dynamic component into the analysis of movement formation. [ABSTRACT FROM AUTHOR]