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Environmental Research Letters | 2011

Statistical confirmation of indirect land use change in the Brazilian Amazon

Eugenio Arima; Peter Richards; Robert Walker; Marcellus M. Caldas

Expansion of global demand for soy products and biofuel poses threats to food security and the environment. One environmental impact that has raised serious concerns is loss of Amazonian forest through indirect land use change (ILUC), whereby mechanized agriculture encroaches on existing pastures, displacing them to the frontier. This phenomenon has been hypothesized by many researchers and projected on the basis of simulation for the Amazonian forests of Brazil. It has not yet been measured statistically, owing to conceptual difficulties in linking distal land cover drivers to the point of impact. The present article overcomes this impasse with a spatial regression model capable of linking the expansion of mechanized agriculture in settled agricultural areas to pasture conversions on distant, forest frontiers. In an application for a recent period (2003‐2008), the model demonstrates that ILUC is significant and of considerable magnitude. Specifically, a 10% reduction of soy in old pasture areas would have decreased deforestation by as much as 40% in heavily forested counties of the Brazilian Amazon. Evidently, the voluntary moratorium on primary forest conversions by Brazilian soy farmers has failed to stop the deforestation effects of expanding soy production. Thus, environmental policy in Brazil must pay attention to ILUC, which can complicate efforts to achieve its REDD targets.


Proceedings of the National Academy of Sciences of the United States of America | 2009

Protecting the Amazon with protected areas

Robert Walker; Nathan Moore; Eugenio Arima; Stephen G. Perz; Cynthia S. Simmons; Marcellus M. Caldas; Dante Vergara; Claudio Bohrer

This article addresses climate-tipping points in the Amazon Basin resulting from deforestation. It applies a regional climate model to assess whether the system of protected areas in Brazil is able to avoid such tipping points, with massive conversion to semiarid vegetation, particularly along the south and southeastern margins of the basin. The regional climate model produces spatially distributed annual rainfall under a variety of external forcing conditions, assuming that all land outside protected areas is deforested. It translates these results into dry season impacts on resident ecosystems and shows that Amazonian dry ecosystems in the southern and southeastern basin do not desiccate appreciably and that extensive areas experience an increase in precipitation. Nor do the moist forests dry out to an excessive amount. Evidently, Brazilian environmental policy has created a sustainable core of protected areas in the Amazon that buffers against potential climate-tipping points and protects the drier ecosystems of the basin. Thus, all efforts should be made to manage them effectively.


Annals of The Association of American Geographers | 2007

The Amazon Land War in the South of Pará

Cynthia S. Simmons; Robert Walker; Eugenio Arima; Stephen Aldrich; Marcellus M. Caldas

Abstract 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 Brazils 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 regions 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.


Annals of The Association of American Geographers | 2007

Accuracy Assessment for a Simulation Model of Amazonian Deforestation

Robert Gilmore Pontius; Robert Walker; Robert Yao-Kumah; Eugenio Arima; Stephen Aldrich; Marcellus M. Caldas; Dante Vergara

Abstract This article describes a quantitative assessment of the output from the Behavioral Landscape Model (BLM), which has been developed to simulate the spatial pattern of deforestation (i.e. forest fragmentation) in the Amazon basin in a manner consistent with human behavior. The assessment consists of eighteen runs for a section of the Transamazon Highway in the lower basin, where the BLMs simulated deforestation map for each run is compared to a reference map of 1999. The BLM simulates the transition from forest to non-forest in a spatially explicit manner in 20-m × 20-m pixels. The pixels are nested within a hierarchical stratification structure of household lots within larger development rectangles that emanate from the Transamazon Highway. Each of the eighteen runs derives from a unique combination of three model parameters. We have derived novel methods of assessment to consider (1) the nested stratification structure, (2) multiple resolutions, (3) a simpler model that predicts deforestation near the highway, (4) a null model that predicts forest persistence, and (5) a uniform model that has accuracy equal to the expected accuracy of a random spatial allocation. Results show that the models specification of the overall quantity of non-forest is the most important factor that constrains and correlates with accuracy. A large source of location agreement is the BLMs assumption that deforestation within household lots occurs near roads. A large source of location disagreement is the BLMs less than perfect ability to simulate the proportion of deforestation by household lot. This article discusses implications of these results in the context of land change science and dynamic simulation modeling. Eugenio Arima and Marcellus Caldas were affiliated with Michigan State University during the time the work reported in this article was done.


Annals of The Association of American Geographers | 2012

Contentious Land Change in the Amazon's Arc of Deforestation

Stephen Aldrich; Robert Walker; Cynthia S. Simmons; Marcellus M. Caldas; Stephen G. Perz

Land change in the Amazon is driven by numerous factors including fiscal incentives, infrastructure, transportation costs, migration, and household decision making. Largely missing from the story to date, however, is the role of contentious social processes, including contention over land resources. By employing a case study of land conflict over a largeholding in southeastern Pará, Brazil, and a regional-scale statistical model, we describe contentious land change (C-LC) in an area with a long history of antagonism between largeholders and the rural poor. We fuse the conceptual frameworks of political ecology with the methodological approaches of land change science to show that deforestation in the area of study is enhanced due to the interaction of diverse and adversarial agents rather than the independent actions of isolated land managers deforesting according to the dictates of microeconomic optimization. C-LC is a process of global reach and must therefore be added to the topical range of land change science. A combination of the explanatory richness of political ecology with the methodological rigor of land change science greatly enhances our understanding of land change processes.


Journal of Land Use Science | 2015

Land-cover change in the Paraguayan Chaco: 2000–2011

Marcellus M. Caldas; Douglas G. Goodin; Steven Sherwood; Juan M. Campos Krauer; Samantha M. Wisely

Land-use and land-cover change has been a topic that has called the attention of the scientific community for decades. Because of the importance of tropical and subtropical forest ecosystems, investigations into the causes and processes (e.g., underlying and proximate causation) that drive land use and land-cover change have typically concentrated on these regions. Consequently, little work has been done to understand the proximate and underlying drivers of land use and land-cover change in one of the least disturbed forests worldwide, the Paraguayan dry Chaco in South America. This article attempts to fill this gap in the literature by focusing on the processes and drivers behind land-cover change in the Paraguayan Chaco. More specifically, this article links underlying and proximate causes to regional land-cover change. To accomplish this task the study makes use of Moderate Resolution Imaging Spectroradiometer (MODIS) data and census data. Results show major land-cover changes. Different from other dry regions in South America where soybean expansion has been pointed out as main driver of land-cover change, in the Paraguayan Chaco, cattle ranching is a major driver of forest loss.


Proceedings of the National Academy of Sciences of the United States of America | 2015

Opinion: Endogenizing culture in sustainability science research and policy

Marcellus M. Caldas; Matthew R. Sanderson; Martha E. Mather; Melinda D. Daniels; Jason S. Bergtold; Joseph A. Aistrup; Jessica L. Heier Stamm; David A. Haukos; Kyle R. Douglas-Mankin; Aleksey Y. Sheshukov; David López-Carr

Integrating the analysis of natural and social systems to achieve sustainability has been an international scientific goal for years (1, 2). However, full integration has proven challenging, especially in regard to the role of culture (3), which is often missing from the complex sustainability equation. To enact policies and practices that can achieve sustainability, researchers and policymakers must do a better job of accounting for culture, difficult though this task may be.


Geophysical monograph | 2013

Small farmers and deforestation in Amazonia

Eduardo S. Brondizio; Anthony D. Cak; Marcellus M. Caldas; Carlos F. Mena; Richard E. Bilsborrow; Célia Futemma; Thomas Ludewigs; Emilio F. Moran; Mateus Batistella

This chapter discusses the relationship between small farmers land use and deforestation, with particular attention paid to the past 30 years of Amazonian colonization in Brazil and Ecuador. Our analysis calls attention to common features uniting different social groups as small farmers (e.g., social identity, access to land and resources, technology, market and credit), as well as the variability between small farmers in terms of time in the region (from native populations to recent colonists), contribution to regional deforestation, types of land use systems. At a regional level, small farmers contribute to the majority of deforestation events, but ate responsible for only a fraction of the total deforested area in Amazonia. We discuss three misconceptions that have been used to define small farmers and their contribution to the regional economy, development, and deforestation: (1) small farmers have backward land use systems associated with low productivity and extensive deforestation and subsistence production, (2) small farmers contribute to Amazonian deforestation as much as large farmers, and (3) small farmers, particularly colonist farmers, follow an inexorable path of deforestation unless curbed by government action. We conclude the chapter discussing their growing regional importance and the need for more inclusive public concerning infrastructure and services and valorization of resources produced in rural areas of Amazonia.


Environmental Conservation | 2007

Unofficial road building in the Brazilian Amazon: dilemmas and models for road governance

Stephen G. Perz; Christine Overdevest; Marcellus M. Caldas; Robert Walker; Eugenio Arima

Unofficial roads form dense networks in landscapes, generating a litany of negative ecological outcomes, but in frontier areas they are also instrumental in local livelihoods and community development. This trade-off poses dilemmas for the governance of unofficial roads. Unofficial road building in frontier areas of the Brazilian Amazon illustrates the challenges of ‘road governance.’ Both state-based and community-based governance models exhibit important liabilities for governing unofficial roads. Whereas state-based governance has experienced difficulties in adapting to specific local contexts and interacting effectively with local peoples, community-based governance has a mixed record owing to social inequalities and conflicts among local interest groups. A state-community hybrid model may offer more effective governance of unofficial road building by combining the oversight capacity of the state with locally-grounded community management via participatory decision-making.


Disasters | 2015

Predictors of compliance with tornado warnings issued in Joplin, Missouri, in 2011

Bimal Kanti Paul; Mitchel Stimers; Marcellus M. Caldas

Joplin, a city in the southwest corner of Missouri, United States, suffered an EF-5 tornado in the late afternoon of 22 May 2011. This event, which claimed the lives of 162 people, represents the deadliest single tornado to strike the US since modern record-keeping began in 1950. This study examines the factors associated with responses to tornado warnings. Based on a post-tornado survey of survivors in Joplin, it reveals that tornado warnings were adequate and timely. Multivariate logistic regression identified four statistically significant determinants of compliance with tornado warnings: number of warning sources, whether respondents were at home when the tornado struck, past tornado experience, and gender. The findings suggest several recommendations, the implementation of which will further improve responses to tornado warnings.

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Robert Walker

Michigan State University

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