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1.
Conserv Lett ; 10(4): 470-476, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29270225

RESUMO

Rates of deforestation reported by Brazil's official deforestation monitoring system have declined dramatically in the Brazilian Amazon. Much of Brazil's success in its fight against deforestation has been credited to a series of policy changes put into place between 2004 and 2008. In this research, we posit that one of these policies, the decision to use the country's official system for monitoring forest loss in the Amazon as a policing tool, has incentivized landowners to deforest in ways and places that evade Brazil's official monitoring and enforcement system. As a consequence, we a) show or b) provide several pieces of suggestive evidence that recent successes in protecting monitored forests in the Brazilian Amazon may be doing less to protect the region's forests than previously assumed.

2.
Nat Plants ; 2(5): 16043, 2016 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-27243646

RESUMO

Agricultural intensification in the tropics is one way to meet rising global food demand in coming decades(1,2). Although this strategy can potentially spare land from conversion to agriculture(3), it relies on large material inputs. Here we quantify one such material cost, the phosphorus fertilizer required to intensify global crop production atop phosphorus-fixing soils and achieve yields similar to productive temperate agriculture. Phosphorus-fixing soils occur mainly in the tropics, and render added phosphorus less available to crops(4,5). We estimate that intensification of the 8-12% of global croplands overlying phosphorus-fixing soils in 2005 would require 1-4 Tg P yr(-1) to overcome phosphorus fixation, equivalent to 8-25% of global inorganic phosphorus fertilizer consumption that year. This imposed phosphorus 'tax' is in addition to phosphorus added to soils and subsequently harvested in crops, and doubles (2-7 Tg P yr(-1)) for scenarios of cropland extent in 2050(6). Our estimates are informed by local-, state- and national-scale investigations in Brazil, where, more than any other tropical country, low-yielding agriculture has been replaced by intensive production. In the 11 major Brazilian agricultural states, the surplus of added inorganic fertilizer phosphorus retained by soils post harvest is strongly correlated with the fraction of cropland overlying phosphorus-fixing soils (r(2) = 0.84, p < 0.001). Our interviews with 49 farmers in the Brazilian state of Mato Grosso, which produces 8% of the world's soybeans mostly on phosphorus-fixing soils, suggest this phosphorus surplus is required even after three decades of high phosphorus inputs. Our findings in Brazil highlight the need for better understanding of long-term soil phosphorus fixation elsewhere in the tropics. Strategies beyond liming, which is currently widespread in Brazil, are needed to reduce phosphorus retention by phosphorus-fixing soils to better manage the Earth's finite phosphate rock supplies and move towards more sustainable agricultural production.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais , Produtos Agrícolas/crescimento & desenvolvimento , Fertilizantes/estatística & dados numéricos , Fósforo , Brasil , Fazendeiros , Solo/química
3.
Ann Assoc Am Geogr ; 105(4): 806-823, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26985079

RESUMO

Developing the Amazon into a major provider of internationally traded mineral and food commodities has dramatically transformed broad expanses of tropical forests to farm and pasturelands, and to mining sites. The environmental impacts of this transformation, as well as the drivers underlying the process, have already been well documented. In this article we turn our analytical lenses to another, less examined effect of Amazon land use and environmental change, namely the creation and development of new urban areas. Here we argue that urban growth in the Amazon is a direct residual of international interest in the production of traded commodities, and of the capacity of local urban residents to capture capital and value before it is extracted from the region. Specifically, we suggest that urban growth is occurring fastest where cities have access to both rural export commodities and export corridors. We also show correlations between urban growth and lower rural population density, and cities' capacities to draw migrants from beyond their immediate rural surroundings. More broadly, we argue that urbanization in the Amazon is better interpreted as a symptom rather than a driver of the region's land use and land cover change.

4.
Popul Res Policy Rev ; 33(6): 915-936, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25419021

RESUMO

As urbanization rates rise globally, it becomes increasingly important to understand the factors associated with urban out-migration. In this paper, we examine the drivers of urban out-migration among young adults in two medium-sized cities in the Brazilian Amazon-Altamira and Santarém-focusing on the roles of social capital, human capital, and socioeconomic deprivation. Using household survey data from 1,293 individuals in the two cities, we employ an event history model to assess factors associated with migration and a binary logit model to understand factors associated with remitting behavior. We find that in Altamira, migration tends to be an individual-level opportunistic strategy fostered by extra-local family networks, while in Santarém, migration tends to be a household-level strategy driven by socioeconomic deprivation and accompanied by remittances. These results indicate that urban out-migration in Brazil is a diverse social process, and that the relative roles of extra-local networks versus economic need can function quite differently between geographically proximate but historically and socioeconomically distinct cities.

5.
Environ Res Lett ; 9(3)2014.
Artigo em Inglês | MEDLINE | ID: mdl-25574186

RESUMO

Garrett et al's recent letter (2013 Environ. Res. Lett.8 044055) shows the trade value of Brazil's production of non-genetically modified (GM) crops, and argues that production for this niche market laid the foundation for the expansion of a variety of non-GM and eco-certification systems. We argue that the conditions underlying the development and perpetuation of the non-GM certification systems are transient. The expansion of soy production has dampened the conditions that promoted the dominance of non-GM soy in the region. The state at the heart of the production of conventional soy, Mato Grosso, already has transitioned to almost 90% GM soy in the most recent agricultural season. The continued viability of eco-certification systems depends on strengthening institutions on the demand side, and ensuring farm-level costs on the supply side match price premiums reaching the farm level.

6.
PLoS One ; 10(4): e0122510, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25919305

RESUMO

In this research we consider the impact of export-driven, soybean agriculture in Mato Grosso on regional economic growth. Here we argue that the soybean sector has served as a motor to the state's economy by increasing the demand for services, housing, and goods, and by providing a source of investment capital to the non-agricultural sector. Specifically, we show that each square kilometer of soybean production supports 2.5 formal sector jobs outside of agriculture, and the equivalent of approximately 150,000US in annual, non-agricultural GDP. We also show that annual gains in non-agricultural employment and GDP are closely tied to soybean profitability, and thus vary from year to year. However, while this article highlights the potential of the agricultural sector as a driver of regional economic growth, it also acknowledges that this growth has been sustained by profits determined by externally set prices and the rate of exchange, and that future growth trajectories will be susceptible to potential currency of market shocks. We also show that while Mato Grosso's economic growth has come at a significant cost to the environment, value added by the agriculture sector, directly and indirectly, has surpassed the value of the CO2-e emitted through land clearings.


Assuntos
Produtos Agrícolas/economia , Desenvolvimento Econômico/tendências , Glycine max/crescimento & desenvolvimento , Reforma Urbana/tendências , Brasil , Países em Desenvolvimento/economia , Emprego/economia , Emprego/tendências , Meio Ambiente , Modelos Econômicos , Fatores Socioeconômicos
7.
Soc Sci Res ; 43: 74-91, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24267754

RESUMO

Rural settlement in previously sparsely occupied areas of the Brazilian Amazon has been associated with high levels of forest loss and unclear long-term social outcomes. We focus here on the micro-level processes in one settlement area to answer the question of how settler and farm endowments affect household poverty. We analyze the extent to which poverty is sensitive to changes in natural capital, land use strategies, and biophysical characteristics of properties (particularly soil quality). Cumulative time spent in poverty is simulated using Markovian processes, which show that accessibility to markets and land use system are especially important for decreasing poverty among households in our sample. Wealtheir households are selected into commercial production of perennials before our initial observation, and are therefore in poverty a lower proportion of the time. Land in pasture, in contrast, has an independent effect on reducing the proportion of time spent in poverty. Taken together, these results show that investments in roads and the institutional structures needed to make commercial agriculture or ranching viable in existing and new settlement areas can improve human well-being in frontiers.


Assuntos
Agricultura , Desenvolvimento Econômico , Meio Ambiente , Características da Família , Propriedade , Pobreza , População Rural , Criação de Animais Domésticos , Brasil , Comércio , Conservação dos Recursos Naturais , Ecossistema , Humanos , Renda , Recursos Naturais , Rios , Classe Social , Solo , Meios de Transporte
8.
Philos Trans R Soc Lond B Biol Sci ; 368(1619): 20120168, 2013 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-23610174

RESUMO

The Brazilian agro-industrial frontier in Mato Grosso rapidly expanded in total area of mechanized production and in total value of production in the last decade. This article shows the spatial pattern of that expansion from 2000 to 2010, based on novel analyses of satellite imagery. It then explores quantitatively and qualitatively the antecedents and correlates of intensification, the expansion of the area under two crops per year. Double cropping is most likely in areas with access to transportation networks, previous profitable agricultural production, and strong existing ties to national and international commodity markets. The article concludes with an exploration of the relationship between double cropping and socioeconomic development, showing that double cropping is strongly correlated with incomes of all residents of a community and with investments in education. We conclude that double cropping in Mato Grosso is very closely tied to multiple indicators of socioeconomic development.


Assuntos
Agricultura/economia , Agricultura/métodos , Conservação dos Recursos Naturais/métodos , Brasil , Produtos Agrícolas , Política Ambiental , Renda , Análise de Regressão , Fatores Socioeconômicos , Glycine max , Análise Espacial
9.
12.
Acta Amazon ; 41(2): 223-232, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-24639597

RESUMO

The objective of this article is to present Polarization of Agrarian Structure as a single, more complete representation than models emphasizing rural exodus and consolidation of land into large agropastoral enterprises of the dynamics of changing land distribution, land use / cover, and thus the rural milieu of Amazonia. Data were collected in 2003 using social surveys on a sample of 587 lots randomly selected from among 5,086 lots on a cadastral map produced in the 1970s. Georeferencing of current property boundaries in the location of these previously demarcated lots allows us to relate sociodemographic and biophysical variables of the surveyed properties to the changes in boundaries that have occurred since the 1970s. As have other authors in other Amazonian regions, we found concentration of land ownership into larger properties. The approach we took, however, showed that changes in the distribution of land ownership is not limited to the appearance of larger properties, those with 200 ha or more; there also exists substantial division of earlier lots into properties with fewer than five hectares, many without any agropastoral use. These two trends are juxtaposed against the decline in establishments with between five and 200 ha. The variation across groups in land use / land cover and population distribution shows the necessity of developing conceptual models, whether from socioeconomic, demographic or environmental perspectives, look beyond a single group of people or properties.

13.
Acta amaz. ; 41(2)2011.
Artigo em Português | VETINDEX | ID: vti-450659

RESUMO

The objective of this article is to present Polarization of Agrarian Structure as a single, more complete representation than models emphasizing rural exodus and consolidation of land into large agropastoral enterprises of the dynamics of changing land distribution, land use / cover, and thus the rural milieu of Amazonia. Data were collected in 2003 using social surveys on a sample of 587 lots randomly selected from among 5,086 lots on a cadastral map produced in the 1970s. Georeferencing of current property boundaries in the location of these previously demarcated lots allows us to relate sociodemographic and biophysical variables of the surveyed properties to the changes in boundaries that have occurred since the 1970s. As have other authors in other Amazonian regions, we found concentration of land ownership into larger properties. The approach we took, however, showed that changes in the distribution of land ownership is not limited to the appearance of larger properties, those with 200 ha or more; there also exists substantial division of earlier lots into properties with fewer than five hectares, many without any agropastoral use. These two trends are juxtaposed against the decline in establishments with between five and 200 ha. The variation across groups in land use / land cover and population distribution shows the necessity of developing conceptual models, whether from socioeconomic, demographic or environmental perspectives, look beyond a single group of people or properties.


O objetivo deste artigo é apresentar a polarização da estrutura fundiária como uma expressão mais completa das dinâmicas fundiárias, do uso-cobertura da terra e, consequentemente, do meio rural na Amazônia do que modelos explicativos que enfatizam o êxodo rural e a consolidação de grandes estabelecimentos agropecuários. Os dados foram coletados em levantamento realizado no entorno de Santarém-PA, em 2003, nos locais de 587 lotes rurais selecionados aleatoriamente por amostragem estratificada de 5.086 lotes existentes em mapas da década de 1970. O georreferenciamento permitiu comparar a estrutura fundiária nos dois momentos e relacionar variáveis sociodemográficas e biofísicas dos estabelecimentos encontrados. Detectou-se concentração fundiária, corroborando o documentado por outros autores em outras porções da Amazônia. No entanto, a perspectiva adotada revela que a variação na estrutura fundiária não se limitou ao aparecimento de estabelecimentos maiores, com 200 hectares ou mais, mas se deu também pela divisão dos lotes originais em estabelecimentos com menos de cinco hectares, muitos das quais sem uso agropecuário, em contrapartida à redução de estabelecimentos entre cinco e 200 ha. As especificidades de cada grupo de estabelecimentos com relação ao uso-cobertura da terra e a distribuição da população chamam a atenção para a necessidade de se buscar modelos explicativos - seja da perspectiva socioeconômica, demográfica ou ambiental - que não se fixem exclusivamente em um único processo, grupo de pessoas ou de estabelecimentos.

14.
Acta amaz ; Acta amaz;41(2): 223-232, 2011. mapas, tab, graf
Artigo em Português | LILACS, VETINDEX | ID: lil-586477

RESUMO

O objetivo deste artigo é apresentar a polarização da estrutura fundiária como uma expressão mais completa das dinâmicas fundiárias, do uso-cobertura da terra e, consequentemente, do meio rural na Amazônia do que modelos explicativos que enfatizam o êxodo rural e a consolidação de grandes estabelecimentos agropecuários. Os dados foram coletados em levantamento realizado no entorno de Santarém-PA, em 2003, nos locais de 587 lotes rurais selecionados aleatoriamente por amostragem estratificada de 5.086 lotes existentes em mapas da década de 1970. O georreferenciamento permitiu comparar a estrutura fundiária nos dois momentos e relacionar variáveis sociodemográficas e biofísicas dos estabelecimentos encontrados. Detectou-se concentração fundiária, corroborando o documentado por outros autores em outras porções da Amazônia. No entanto, a perspectiva adotada revela que a variação na estrutura fundiária não se limitou ao aparecimento de estabelecimentos maiores, com 200 hectares ou mais, mas se deu também pela divisão dos lotes originais em estabelecimentos com menos de cinco hectares, muitos das quais sem uso agropecuário, em contrapartida à redução de estabelecimentos entre cinco e 200 ha. As especificidades de cada grupo de estabelecimentos com relação ao uso-cobertura da terra e a distribuição da população chamam a atenção para a necessidade de se buscar modelos explicativos - seja da perspectiva socioeconômica, demográfica ou ambiental - que não se fixem exclusivamente em um único processo, grupo de pessoas ou de estabelecimentos.


The objective of this article is to present Polarization of Agrarian Structure as a single, more complete representation than models emphasizing rural exodus and consolidation of land into large agropastoral enterprises of the dynamics of changing land distribution, land use / cover, and thus the rural milieu of Amazonia. Data were collected in 2003 using social surveys on a sample of 587 lots randomly selected from among 5,086 lots on a cadastral map produced in the 1970s. Georeferencing of current property boundaries in the location of these previously demarcated lots allows us to relate sociodemographic and biophysical variables of the surveyed properties to the changes in boundaries that have occurred since the 1970s. As have other authors in other Amazonian regions, we found concentration of land ownership into larger properties. The approach we took, however, showed that changes in the distribution of land ownership is not limited to the appearance of larger properties, those with 200 ha or more; there also exists substantial division of earlier lots into properties with fewer than five hectares, many without any agropastoral use. These two trends are juxtaposed against the decline in establishments with between five and 200 ha. The variation across groups in land use / land cover and population distribution shows the necessity of developing conceptual models, whether from socioeconomic, demographic or environmental perspectives, look beyond a single group of people or properties.


Assuntos
Ecossistema Amazônico
15.
Nova Econ ; 19(2): 325-357, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20927199

RESUMO

What motivates family members to share resources? Past research argues for, on the one hand, love and altruism, and on the other, the expectation of reciprocity. Drawing on this literature, this paper examines intergenerational transfers between small farmers and their non-coresident children in the rural area around the city of Altamira, Pará, Brazil. We apply GoM (Grade of Membership) models to create profiles of private transfers, using data collected in 2005 by a team from Indiana University. The results show three profiles: low intergenerational transfers, high levels of transfers of visits and help, and high levels of transfers of visits and money. There is no clear difference in profile by birth order, but we do find sex differences in profile. Men are more likely to send money while women provide time transfers (work and visits). Upward transfers are most common from children with high levels of education or living in urban areas, suggesting a repayment of prior investments made by parents. Thus, our empirical evidence supports theories arguing that transfers are motivated by intertemporal contracts between parents and children, and that altruistic theories of family transfers should be rethought among rural agricultural populations in contexts characterized by many environmental and institutional challenges.

16.
Rev. bras. estud. popul ; 24(2): 263-275, jul.-dez. 2007. ilus, mapas
Artigo em Português | LILACS | ID: lil-472082

RESUMO

Este artigo apresenta a estratégia usada em uma pesquisa realizada em Santarém - PA, em 2003, para amostrar lotes delimitados em mapas do Incra e as unidades domésticas ali existentes, de modo a capturar as mudanças populacionais e ambientais na escala das propriedades rurais e na da região. A amostra foi selecionada conforme a distribuição dos lotes ao longo de quatro eixos rodoviários relacionados a distintos processos de ocupação. Em cada um dos eixos foram selecionadas aleatoriamente 20 células com 9km². Em cada uma delas, foram selecionados aleatoriamente os lotes que deveriam ser visitados. No campo, entrevistaram-se todas as unidades domésticas existentes em cada um dos lotes selecionados. Descreve-se a amostragem por segmentação sucessiva da área de estudo, destacando-se como os dados resultantes podem ser usados diferentemente nas escalas das unidades domésticas, dos lotes e da região, conforme as questões e variáveis de interesse.


This article describes the strategy used in a study carried out in Santarém, State of Parß, Brazil, in 2003, to sample plots represented on maps produced by the Brazilian Government's Land Reform Department (INCRA). The purpose of this sampling strategy is to describe demographic and environmental changes on the scale of the rural landholdings and on a regional scale. The sample was chosen according to the distribution of plots of land along four different roads that underwent different processes of occupation. Twenty cells of 9km2 each were chosen at random along each road and, in each direction, plots were chosen to be visited. In the field work, persons at all the domestic units existing in each of the plots selected were interviewed. Sampling carried out by successive segmentation of the area of study is described, as well as the way in which the resulting data can be used differently on the scales of domestic units, plots of land, and regions, according to the questions and variables of interest.


Este artículo presenta la estrategia usada en una investigación realizada en Santarém - PA, en 2003, para mostrar lotes delimitados en mapas del Incra [Instituto Nacional de Colonización y Reforma Agraria] y las unidades domésticas allí existentes, de modo de captar los cambios poblacionales y ambientales en la escala de las propiedades rurales y en la de la región. La muestra fue seleccionada de acuerdo a la distribución de los lotes a lo largo de cuatro ejes viales relacionados a distintos procesos de ocupación. En cada uno de los ejes fueron seleccionadas aleatoriamente 20 células con 9km2. En cada una de ellas, fueron seleccionados aleatoriamente los lotes que deberían ser visitados. En el área establecida, se entrevistaron todas las unidades domésticas existentes en cada uno de los lotes seleccionados. Se describe el muestreo por segmentación sucesiva del área de estudio, destacándose, como los datos resultantes pueden ser usados de forma diferente en las escalas de las unidades domésticas, de los lotes y de la región, de acuerdo a los aspectos y a las variables de interés.


Assuntos
Humanos , Masculino , Feminino , Agricultura , Amostragem por Conglomerados , População Rural , Brasil , Demografia , Fatores Socioeconômicos
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