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1.
Article in English | MEDLINE | ID: mdl-37850530

ABSTRACT

Changes in land use and land cover (LULC) have significant implications for biodiversity, ecosystem functioning, and deforestation. Modeling LULC changes is crucial to understanding anthropogenic impacts on environmental conservation and ecosystem services. Although previous studies have focused on predicting future changes, there is a growing need to determine past scenarios using new assessment tools. This study proposes a methodology for LULC past scenario generation based on transition analysis. Aiming to hindcast LULC scenario in 1970 based on the transition analysis of the past 35 years (from 1985 to 2020), two machine learning algorithms, multilayer perceptron (MLP) and similarity weighted (SimWeight), were employed to determine the driver variables most related to conversions in LULC and to simulate the past. The study focused on the Aristida spp. grasslands in the Uruguayan savannas, where native grasslands have been extensively converted to agricultural areas. Land use and land cover data from the MapBiomas project were integrated with spatial variables such as altimetry, slope, pedology, and linear distances from rivers, roads, urban areas, agriculture, forest, forestry, and native grasslands. The accuracy of the predicted maps was assessed through stratified random sampling of reference images from the Multispectral Scanner (MSS) sensor. The results demonstrate a reduction of approximately 659 934 ha of native grasslands in the study area between 1985 and 2020, directly proportional to the increase in cultivable areas. The MLP algorithm exhibited moderate performance, with notable errors in classifying agriculture and grassland areas. In contrast, the SimWeight algorithm displayed better accuracy, particularly in distinguishing grassland and agriculture classes. The modeled map using SimWeight accurately represented the transitions between grassland and agriculture with a high level of agreement. By modeling the 1970s scenario using the SimWeight model, it was estimated that the Aristida spp. grasslands experienced a substantial reduction in grassland coverage, ranging from 9982.31 to 10 022.32 km2 between 1970 and 2020. This represents a range of 60.8%-61.07% of the total grassland area in 1970. These findings provide valuable insights into the driving factors behind land use change in the Aristida spp. grasslands and offer useful information for land management, conservation, and sustainable development in the region. The study's main contribution lies in the hindcasting of past LULC scenarios, utilizing a tool used primarily for forecasting future scenarios. Integr Environ Assess Manag 2023;00:1-16. © 2023 SETAC.

2.
Environ Monit Assess ; 195(10): 1224, 2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37725180

ABSTRACT

Resistance models may quantify the ability of the landscape to impede species' movement and represent suitable habitats. Moreover, the performance of resistance models parameterized by land-use/land cover attributes evidence that the integrity of the environments subject to urban sprawl is poorly understood. In this sense, the study assumed we could identify the forest functional connectivity in a landscape considering the disparity in the landscape mosaic. In this context, we sought to develop a landscape resistance index through structural equation modeling (SEM), supported by the criteria of heat emission, biomass, and anthropogenic barriers, obtained by remote sensing, called observed variables. The landscape studied in the Green Belt Biosphere Reserve of São Paulo has significant remnants of the Atlantic Forest, a biodiversity hotspot. However, our results indicated criteria variability in the landscape modeled through the SEM, obtaining a significant adjustment of the landscape resistance index, with comparative fit index (CFI) of 1.00 and root mean square error of approximation (RMSEA) of 0.00. The index reflects the resistance levels of the land use/land cover, expressed by the class interval, ranging from 0% (1.73) to 100% (493.88), with the highest values associated with the anthropized uses and forest isolation. Thus, our index based on environmental attributes reflects the structure of functional forest connectivity and offers a framework to design forest corridors across landscapes.


Subject(s)
Environmental Monitoring , Forests , Brazil , Biodiversity , Biomass
3.
Environ Res ; 227: 115729, 2023 06 15.
Article in English | MEDLINE | ID: mdl-36948283

ABSTRACT

The emission of soil carbon dioxide (CO2) in agricultural areas is a process that results from the interaction of several factors such as climate, soil, and land management practices. Agricultural practices directly affect the carbon dynamics between the soil and atmosphere. Herein, we evaluated the temporal variability (2020/2021 crop season) of soil CO2 emissions and its relationship with related variables, such as the CO2 flux model, enhanced vegetation index (EVI), gross primary productivity (GPP), and leaf area index (LAI) from orbital data and soil temperature, soil moisture, and soil CO2 emissions from in situ collections from native forests, productive pastures, degraded pastures, and areas of high-yield potential soybean and low-yield potential soybean production. A significant influence (p < 0.01) was observed for all variables and between the different land uses and occupation types. September and October had lower emissions of soil CO2 and low means of soil moisture and soil temperature, and no differences were observed among the treatments. On the other hand, there was a significant effect of the CO2 flux model in productive pastures, high-yield potential soybean areas, and low-yield potential soybean areas. The months with the highest CO2 flux values in the model, regardless of land use and land cover, were October and November, which is the beginning of the rainy season. There were positive correlations between soil CO2 emissions and GPP (0.208), LAI (0.354), EVI (0.363), and soil moisture (0.280) and negative correlations between soil CO2 emissions and soil temperature (-0.240) and CO2 flux model (-0.314) values. Land use and land cover showed negative correlations with these variables, except for the CO2 flux model variable. Soil CO2 emission values were lower for high-yield potential soybean areas (averages from 0.834 to 6.835 µmol m-2 s-1) and low-yield potential soybean areas (from 0.943 to 5.686 µmol m-2 s-1) and higher for native forests (from 2.279 to 8.131 µmol m-2 s-1), whereas the opposite was true for the CO2 flux model.


Subject(s)
Carbon Dioxide , Forests , Carbon Dioxide/analysis , Brazil , Agriculture/methods , Soil , Methane
4.
Environ Monit Assess ; 195(1): 179, 2022 Dec 07.
Article in English | MEDLINE | ID: mdl-36478227

ABSTRACT

Vegetational succession assessment is an important step for better management practices, providing relevant quantitative and qualitative information. With the advancements of remote sensing algorithms and access to data, land use and land cover (LULC) monitoring has become increasingly feasible and important for the evaluation of changes in the landscape at different spatial and temporal scales. This study aims to analyze the vegetation succession achieved by a project funded by the Brazilian Environmental Ministry (Ministério do Meio Ambiente, in Portuguese) intended to recover degraded areas. A 2014 and a 2019 LULC map was generated using high-resolution (10 cm) images. Given the great challenge of classifying high-resolution images, three classification algorithms were compared. The techniques to regenerate degraded areas were efficient to increase arboreal vegetation area by more than 30% between 2014 and 2019. Land cover and land use change monitoring is of paramount importance to strengthen sustainable practices, especially in the highly threatened Atlantic Forest biome. This study also shows that funding opportunities are essential for projects that make such actions possible, including the present research and the analysis of environmental regeneration.


Subject(s)
Environmental Monitoring , Brazil
5.
Sci Total Environ ; 844: 157138, 2022 Oct 20.
Article in English | MEDLINE | ID: mdl-35798117

ABSTRACT

The trade-off between conservation of natural resources and agribusiness expansion is a constant challenge in Brazil. The fires used to promote agricultural expansion increased in the last decades. While studies linking annual fire occurrence and rainfall seasonality are common, the relationship between fires, land use, and land cover remains understudied. Here, we investigated the frequency of the fires and performed a trend analysis for monthly, seasonal, and annual fires in three different biomes: Cerrado, Pantanal, and Atlantic Forest. We used burned area and integrated models in distinct scales (interannual, intraseasonal, and monthly) using Probability Density Functions (PDFs). The best fitting was found for Generalized Extreme Values (GEV) distribution at all three biomes from the several PDFs tested. We found the most fire in the Pantanal (wetlands), followed by Cerrado (Brazilian Savanna) and Atlantic Forest (Semideciduous Forest). Our findings indicated that land use and land cover trends changed over the years. There was a strong correlation between fire and agricultural areas, with increasing trends pointing to land conversion to agricultural areas in all biomes. The high probability of fire indicates that expanding agricultural areas through the conversion of natural biomes impacts several natural ecosystems, transforming land cover and land use. This land conversion is promoting more fires each year.


Subject(s)
Conservation of Natural Resources , Ecosystem , Fires , Agriculture , Brazil , Forests
6.
Environ Manage ; 69(2): 438-448, 2022 02.
Article in English | MEDLINE | ID: mdl-35013793

ABSTRACT

Developing conservation strategies to mitigate cumulative impacts requires the understanding of historic land use and land cover changes at the regional scale. By using a multisensory and multitemporal approach, we identified the major changes driving cumulative impacts on native vegetation in northeastern Amazon. Comparing two regions, one with mining as the key driver and another where mining is associated with other industrial activities (cellulose), we explore the land use and land cover historic dynamics and derive implications for the assessment of cumulative impacts. Transitions of forest cover to pastureland, silviculture, and urban expansion were mapped in detail over a 20-year period, revealing that silviculture growth cleared more forests than pastureland expansion when associated with pulp mill activities and kaolin mining. In contrast, in a region with gold and iron mining, pastureland expansion was more relevant, clearing mainly areas surrounding new roads. This research shows that the interplay of major mining and industrial investments can produce cumulative losses of native vegetation, depending on the associated industries and infrastructure required for the project development. Our findings emphasize that the definition of spatial and temporal boundaries for the assessment of cumulative impacts must consider different trends in impact accumulation and changes in their spatial distribution over time.


Subject(s)
Conservation of Natural Resources , Forests , Brazil , Mining
7.
J Environ Manage ; 282: 111973, 2021 Mar 15.
Article in English | MEDLINE | ID: mdl-33461090

ABSTRACT

Primary forests in seasonally dry tropical regions have undergone intense land-use/cover change, ranging from widespread shifting agriculture to land clearing for livestock production systems, and selective logging. Despite the importance of tropical dry forests (TDF), little is known about the implications of carbon (C) emissions from deforestation in local, national, and global scales. Therefore, the main objective of this study is to quantify and understand the processes that drive major C losses of this ecosystem in Mexico. Also, we evaluated the applicability of the already published above ground biomass (AGB) maps to quantify and allocate changes in C stocks. The results suggest that biomass maps can be used to capture the patterns of AGB distribution and to identify the driving forces of C emissions. The C losses are more related to socioeconomic drivers than biophysical characteristics like topography and climate. Besides, this study shows that published current AGB maps may be used for landscape management, including conservation and restoration areas.


Subject(s)
Carbon , Ecosystem , Biomass , Carbon/analysis , Conservation of Natural Resources , Forests , Mexico , Trees , Tropical Climate
8.
J Environ Manage ; 272: 111083, 2020 Oct 15.
Article in English | MEDLINE | ID: mdl-32677623

ABSTRACT

Assessing management effectiveness in protected areas is a fundamental instrument to achieve socio-biodiversity protection goals. This study aimed to analyze the management effectiveness of Cunhambebe State Park (from now on, "PEC") in the State of Rio de Janeiro in Brazil, from the perception of stakeholders and the multi-temporal analysis of land use and land cover between 1998 and 2018. We used the Rapid Assessment and Prioritization of Protected Area Management method for a participatory approach. Seventy-two indicators were used and applied to assess the perception of stakeholders related to the Advisory Council. The management effectiveness of PEC was classified as moderately satisfactory (63.41%). Indicators of "Legal security", "Vulnerability", "Site design and planning" and "Financial resources" revealed the weaknesses and threats of management and what should be the priority projects for better effectiveness. Through the multi-temporal analysis, we identified that the advances of pasture and urban areas are the highest pressures and threats, as perceived by stakeholders. In our case study, we provide evidence of actions that must be performed by the PEC management team. These actions must consider the weaknesses and threats presented by the SWOT analysis. Finally, we recommend some political and management measures: 1) Financial resources for the land regularization of areas overlapping with PEC, 2) Guidelines about PEC areas must be included in the Master Plans of municipalities that cover PEC limits, 3) Technical assistance to improve land management, and 4) Strengthen environmental education initiatives at all school levels.


Subject(s)
Conservation of Natural Resources , Forests , Biodiversity , Brazil
9.
Environ Sci Pollut Res Int ; 27(24): 30034-30049, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32447727

ABSTRACT

Applying the climatological water balance (WB) concept to describe the relationship between climatic seasonality and surface water quality according to different forms of land use and land cover (LULC) is an important issue, but little explored in the literature. In this paper, we evaluate the influence of WB on surface water quality and its impacts when interacting with LULC. We monitored 11 sampling points during the four seasons of the year, from which we estimate WQI (water quality index) and TSI (trophic state index). We found an effect of the seasonality factor on both WQI values (F(3,30) = 12.472; p < 0.01) and in TSI values (F(3,30) = 6.967; p < 0.01). We noticed that LULC interferes in the way that the water balance influences the WQI and TSI values since in sampling points closest to higher urban density, with little or no riparian protection, the correlation between water balance and water quality was lower. In the stations that had the lowest water surplus and deficit, there was positive linearity between water balance and WQI. However, in the seasons when the surplus and water deficit recorded were extreme, there was no linearity. We conclude that water deficiency impairs the quality of surface water. In the extreme surplus water season, the homogeneity of WQI samples was lower, suggesting a higher interaction between rainwater and LULC. This study contributes to design management strategies of water resources, considering the climatic seasonality for optimization.


Subject(s)
Rivers , Water Quality , Brazil , Environmental Monitoring , Water Pollution/analysis
10.
Semina Ci. agr. ; 38(3): 1145-1160, maio-jun. 2017. mapas, tab
Article in English | VETINDEX | ID: vti-13453

ABSTRACT

The objective of this study is to expand the mapping of land use and land cover, as well as of the permanent preservation areas (PPAs), and identify land misuse areas in the PPAs in the Tailândia municipality in the state of Pará, which is part of the Amazon biome. Remote sensing techniques and geographic information systems (GIS) were used to achieve these goals. Mapping and classification for the year 2012 were made by visual interpretation of images obtained from the RapidEye satellite, which has a 5 m spatial resolution. In this work, we identified nine classes of land use and land cover. From the hydrography vectors it was possible to determinate the Permanent Preservation Areas of the bodies of water according to the environmental legislation. Analysis of misuse in the PPAs was made by crossingchecking the land use and land cover data with that of the PPAs. The results show that 53% of the municipality (2,347.64 km²) is occupied by human activities. Livestock farming is the activity that has most increased the use of area (30%), followed by altered vegetation (14.6%) and palm oil (7.2%). The PPAs have a high percentage of misuse (47.12%), with livestock being the largest contributor, occupying 26.65% of the PPAs, followed by altered vegetation (12.64%) and palm oil (4.29%). Therefore, the main objective in Tailândia is to reconcile economic activity with sustainable development. It is important to emphasize the partnerships between the government, research institutions, regulatory agencies, states departments and local communities, else it would be impossible to monitor or control an area as vast as the Amazon.(AU)


O presente trabalho tem como objetivo elaborar o mapeamento de uso e cobertura da terra bem como mapear as Áreas de Preservação Permanente (APPs) e identificar as atividades infratoras em APPs no município de Tailândia no estado do Pará, que faz parte do bioma da Amazônia. Para este fim, técnicas de sensoriamento remoto e Sistema de Informação Geográfica foram utilizadas. O mapeamento e a classificação foram realizados por interpretação visual das imagens de satélite RapidEye com 5 m de resolução espacial para o ano de 2012. Foram identificadas nove classes de uso e cobertura da terra. A partir dos vetores de hidrografia foi possível determinar as Áreas de Preservação Permanente dos corpos dagua de acordo com a legislação ambiental. A análise do uso indevido em APPs foi feito a partir do cruzamento de dados do uso e cobertura da terra com as APPs. Segundo os dados obtidos 53% do município (2.347,64 km²) são ocupados por atividades antrópicas. A pastagem é a atividade que possui maior área de uso (30%), seguido pela vegetação alterada (14,6%) e dendê (7,2%). As APPs possuem uma alta porcentagem de uso indevido (47,12%), sendo que a pastagem é a maior infratora, ocupando 26,65% das APPs, seguida pela vegetação alterada (12,64%) e dendê (4,29%). Portanto o principal desafio do município é conciliar a atividade econômica e o desenvolvimento sustentável, sendo importante salientar que são necessárias as parcerias entre o Estado, as instituições de pesquisas, órgãos fiscalizadores, secretarias estaduais e comunidades locais, pois sem essas parcerias seria impossível fiscalizar ou controlar uma área tão imensa quanto o da Amazônia Legal.(AU)


Subject(s)
Geographic Mapping , Preservation, Biological/standards , Preservation, Biological/veterinary
11.
Semina ciênc. agrar ; 38(3): 1145-1160, maio-jun. 2017. map, tab
Article in English | VETINDEX | ID: biblio-1500797

ABSTRACT

The objective of this study is to expand the mapping of land use and land cover, as well as of the permanent preservation areas (PPAs), and identify land misuse areas in the PPAs in the Tailândia municipality in the state of Pará, which is part of the Amazon biome. Remote sensing techniques and geographic information systems (GIS) were used to achieve these goals. Mapping and classification for the year 2012 were made by visual interpretation of images obtained from the RapidEye satellite, which has a 5 m spatial resolution. In this work, we identified nine classes of land use and land cover. From the hydrography vectors it was possible to determinate the Permanent Preservation Areas of the bodies of water according to the environmental legislation. Analysis of misuse in the PPAs was made by crossingchecking the land use and land cover data with that of the PPAs. The results show that 53% of the municipality (2,347.64 km²) is occupied by human activities. Livestock farming is the activity that has most increased the use of area (30%), followed by altered vegetation (14.6%) and palm oil (7.2%). The PPAs have a high percentage of misuse (47.12%), with livestock being the largest contributor, occupying 26.65% of the PPAs, followed by altered vegetation (12.64%) and palm oil (4.29%). Therefore, the main objective in Tailândia is to reconcile economic activity with sustainable development. It is important to emphasize the partnerships between the government, research institutions, regulatory agencies, states departments and local communities, else it would be impossible to monitor or control an area as vast as the Amazon.


O presente trabalho tem como objetivo elaborar o mapeamento de uso e cobertura da terra bem como mapear as Áreas de Preservação Permanente (APPs) e identificar as atividades infratoras em APPs no município de Tailândia no estado do Pará, que faz parte do bioma da Amazônia. Para este fim, técnicas de sensoriamento remoto e Sistema de Informação Geográfica foram utilizadas. O mapeamento e a classificação foram realizados por interpretação visual das imagens de satélite RapidEye com 5 m de resolução espacial para o ano de 2012. Foram identificadas nove classes de uso e cobertura da terra. A partir dos vetores de hidrografia foi possível determinar as Áreas de Preservação Permanente dos corpos d’agua de acordo com a legislação ambiental. A análise do uso indevido em APPs foi feito a partir do cruzamento de dados do uso e cobertura da terra com as APPs. Segundo os dados obtidos 53% do município (2.347,64 km²) são ocupados por atividades antrópicas. A pastagem é a atividade que possui maior área de uso (30%), seguido pela vegetação alterada (14,6%) e dendê (7,2%). As APPs possuem uma alta porcentagem de uso indevido (47,12%), sendo que a pastagem é a maior infratora, ocupando 26,65% das APPs, seguida pela vegetação alterada (12,64%) e dendê (4,29%). Portanto o principal desafio do município é conciliar a atividade econômica e o desenvolvimento sustentável, sendo importante salientar que são necessárias as parcerias entre o Estado, as instituições de pesquisas, órgãos fiscalizadores, secretarias estaduais e comunidades locais, pois sem essas parcerias seria impossível fiscalizar ou controlar uma área tão imensa quanto o da Amazônia Legal.


Subject(s)
Geographic Mapping , Preservation, Biological/standards , Preservation, Biological/veterinary
12.
Acta amaz. ; 47(1): 29-38, jan.-mar. 2017. mapas, tab, graf
Article in English | VETINDEX | ID: vti-688356

ABSTRACT

Although soybean production has been increasing in the state of Rondônia in the last decade, soybean planted area has been estimated indirectly using secondary datasets, which has limited understanding of its spatiotemporal distribution patterns. This study aimed to map and analyze spatial patterns of soybean expansion in Rondônia. We developed a classification technique based on Spectral Mixture Analysis (SMA) derived from Landsat imagery and Decision Tree Classification to detect and map soybean plantations in 2000, 2005, 2010, and 2014. The soybean classification map showed 93% global accuracy, 23% omission and 0% of commission errors for soybean crop fields. The greatest increases of soybean cropped area in the state of Rondônia were observed between 2000-2005 and 2005-2010 time-periods (33,239 ha and 59,628 ha, respectively), mostly located in Southern Rondônia. The expansion of soybean areas to Northern Rondônia (25,627 ha) has mostly occurred in the 2010-2014 time period. We estimate that 95.4% of all newly created soybean plantations, detected by 2014, were established on lands deforested nine or more years earlier. We concluded that the incursion of soybean plantations on lands deforested for other land uses (e.g. ranching) is contributing to their displacement (pastures) from older colonization zones toward more remote frontier areas of the Amazon, exacerbating new deforestation there.(AU)


Os plantios de soja têm aumentado ao Norte e Sul dos municípios de Rondônia na última década, entretanto a área plantada de soja tem sido estimada utilizando dados secundários, o que limita o entendimento da distribuição espaço temporal da soja. Este estudo buscou analisar e mapear os padrões espaciais de expansão da soja em Rondônia. O mapeamento de plantios de soja nos anos 2000, 2005, 2010 e 2014 foi feito a partir de uma técnica de classificação baseada na análise de mistura espectral de imagens Landsat e em uma árvore de decisão. A acurácia global, erros de omissão e comissão para o mapeamento da soja foram 93%, 23% e 0%, respectivamente. Os resultados mostraram que os maiores incrementos da área de soja ocorreram no estado de Rondônia entre os períodos de 2000-2005 e 2005-2010 (33,239 ha e 59,628 ha, respectivamente). A expansão das áreas de soja para o norte de Rondônia (25,627 ha) ocorreu em sua maioria no período de 2010 a 2014. Observou-se que 95,4% de todos os plantios de soja detectados em 2014 ocorreram em áreas com pelo menos nove anos de desmatamento. Além disso, encontramos evidências de que os plantios de soja estão contribuindo para o deslocamento de usos da terra prévios de antigas zonas de colonização, predominantemente pastos que foram empurrados para outras áreas de fronteiras da Amazônia, e lá exacerbando novos desmatamentos.(AU)


Subject(s)
Glycine max , 24444 , Agricultural Zones/statistics & numerical data , Conservation of Natural Resources/statistics & numerical data , Geographic Mapping
13.
J Environ Manage ; 188: 73-84, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-27930958

ABSTRACT

The conversion of natural ecosystems to agricultural land and urban areas plays a threat to the protected areas and the natural ecosystems conservation. The aim of this paper is to provide an analysis of the agricultural expansion and its impact on the landscape spatial and temporal patterns in a buffer zone of a protected area located in the transition zone between the Atlantic Forest and Cerrado, in the State of São Paulo, Brazil. The land use and land cover were mapped between 1971 and 2008 and landscape metrics were calculated to provide a spatiotemporal analysis of the forest structure and the expansion of the croplands. The results showed that the landscape patterns were affected by the economic cycles. The predominant crop surrounding the protected area is sugar cane, which increased by 39% during this period, followed by citrus. This landscape change is connected to the Brazilian oil crisis in 1973. The rapid expansion of sugar cane was largely driven by Brazil's biofuel program, the "Proálcool" (pro-alcohol), a project in 1975 that mixed ethanol with gas for automotive fuel. The forest loss occurred mainly between 1971 and 1988, decreasing the forest cover from 17% in 1971 to 12.7% in 2008. Most of the forest patches are smaller than 50 ha and has low connectivity. Throughout the years, the fragments in the buffer zone have become smaller and with an elongated shape, and the park has become isolated. This forest fragmentation process and the predominance of monoculture lands in the buffer zone threaten the protected areas, and can represent a barrier for these areas to provide the effective biodiversity conservation. The measures proposed are necessary to ensure the capability of this ecosystem to sustain its original biodiversity.


Subject(s)
Agriculture , Biodiversity , Conservation of Natural Resources/methods , Economic Development , Brazil , Crops, Agricultural , Ecosystem , Environment , Forestry/statistics & numerical data , Forests , Saccharum
14.
Rev. bras. estud. popul ; 32(3): 563-585, set.-dez. 2015. tab, graf
Article in Portuguese | LILACS | ID: lil-769923

ABSTRACT

O objetivo deste artigo é analisar a distribuição da população do Pará, a partir de dados do Censo Demográfico 2010 associados a dados de uso e cobertura da terra do TerraClass, dispostos em uma grade estatística. Verifica-se o papel de 113 Áreas Protegidas (AP) - 46 Terras Indígenas, 51 Unidades de Conservação de Uso Sustentável e 16 Unidades de Conservação de Proteção Integral - no gradiente rural-urbano do ponto de vista populacional e em relação aos usos-coberturas da terra nelas existentes. Utilizando um Sistema de Informações Geográficas, os dados relativos às APs, ao uso e cobertura da terra e os censitários foram incorporados à grade estatística. O relacionamento espacial dos planos de informação nas células indica que a população do estado é bastante concentrada, uma tendência que se reproduz nas Áreas Protegidas (o coeficiente de Gini para a distribuição dos domicílios é superior a 0,9). As APs configuram-se como áreas menos populosas e mais florestadas em comparação ao restante do estado. Apesar da presença de extensas porções sem domicílios ocupados e da maior extensão de florestas do Pará (57%), identificam-se nestas áreas usos urbanos associados a outros usos e coberturas da terra. Os resultados indicam que as dinâmicas populacionais e as mudanças nos usos e cobertura da terra estão relacionadas de forma mais ampla, estimulando a reflexão sobre a urbanização e as mudanças no uso e cobertura da terra de forma mais integrada...


The objective of this study is to analyze population distribution in the state of Pará in Brazil using data from the2010 Population Census in association with the land use and land cover data from TerraClass arranged in a statistical grid. The role of 113 Protected Areas (including 46 Indigenous Lands, 51 Sustainable Use Conservation Units and 16 Integral Protection Conservation Units) is analyzed from the standpoint of their demographic rural-urban gradients and in terms of their land use cover. Information on the use and cover of land in Protected Areas along with census data were incorporated into a statistical grid using GIS. The spatial relationship of information layers in the cells indicates that the state's population is highly concentrated in a few areas, a pattern that is reproduced to some extent in the Protected Areas (Gini coefficient for the distribution of households is higher than 0.9). The area of the Protected areas is less populated and retains a greater extension of forested areas, by comparison to the state. Despite having extensive segments devoid of occupied households and the largest expanse of forest coverage (57%) in the state, Protected Areas also have urban areas associated with other uses and land cover change. The results indicate that population dynamics and changes in the uses and covering of land are related in a broader manner, thereby suggesting the need for reflection on urbanization and changes in land use and land cover change within a more integrated approach...


El objetivo de este trabajo es analizar la distribución de la población del estado de Pará en Brasil a partir de información del Censo Demográfico de 2010 asociada a datos de uso y cobertura de la tierra provenientes de TerraClass, dispuestos en una cuadrícula estadística. Se examina el papel que desempeñan 113 Áreas Protegidas, 46 Tierras Indígenas, 51 Unidades de Conservación de Uso Sustentable y 16 Unidades de Conservación de Protección Integral en el gradiente rural-urbano desde el punto de vista de la población y en relación con los usos y la cobertura de la tierra existentes en ellas. La información relativa a las Áreas Protegidas, al uso y la cobertura de la tierra y los datos censales fueron incorporados a la cuadrícula estadística usando un Sistema de Información Geográfica. La relación espacial entre los estratos de información en la cuadrícula indica que la población del estado está bastante concentrada, una tendencia que se reproduce en las Áreas Protegidas (el coeficiente de Gini de la distribución de las viviendas es superior a 0,9). Las Áreas Protegidas se configuran como zonas menos pobladas y con más forestación que el resto del estado. A pesar de la presencia de extensas áreas sin viviendas ocupadas y de la mayor extensión de los bosques de Pará (57%), se identifican en estas áreas usos urbanos asociados a otros usos y coberturas de la tierra. Los resultados indican que las dinámicas de la población y los cambios en los usos y la cobertura de la tierra están relacionados de manera más amplia, estimulando por lo tanto una reflexión más integrada sobre la vinculación entre la urbanización y estos cambios...


Subject(s)
Humans , Population Dynamics , Protected Areas , Residence Characteristics , Urbanization/trends , Brazil , Censuses , Geographic Information Systems
15.
Rev. bras. estud. popul ; 31(1): 191-210, jan.-jun. 2014. tab
Article in Portuguese | LILACS | ID: lil-714758

ABSTRACT

Pensando de forma integrada a relação população-ambiente, o artigo aborda os estudos sobre dinâmica populacional e mudança no uso e cobertura da terra, com foco na contribuição e nos desafios da Demografia. Aproximando-se do tema em meados dos anos 1990, a Demografia teve como principal contribuição destacar a importância dos componentes populacionais nos modelos, antes, colocados como secundários e sob uma perspectiva simples. Demógrafos brasileiros dedicados a questões ambientais, embora tivessem prioritariamente a temática urbana no seu escopo, colaboraram de maneira indireta para a desenvoltura do campo, ao proporem uma releitura sobre relações população-ambiente. O artigo parte do caso da Amazônia brasileira, mostrando como a população foi explorada nas teorias sobre mudanças nos usos e coberturas da terra, passando pelo viés do crescimento populacional durante o período de fronteira agrícola, o modelo de ciclo de vida do domicílio (fecundidade e composição do domicílio) na década de 1990 e, mais recentemente, o enfoque no componente migratório. Para a Demografia, aponta-se como essencial o aprofundamento nos elementos demográficos que não o volume e a inclusão do espaço e seus efeitos. Para a construção da Ciência da Mudança da Terra, destacam-se a incorporação de dinâmicas urbanas nas investigações, a adoção de uma metodologia multiescalar e o exercício do diálogo entre as diversas disciplinas, incorporando mais sistematicamente a contribuição da Demografia...


This paper is about studies on the relationships between environment and population from an integrated perspective, and changes in the use of the land cover, focusing on the contributions and challenges for demography. Demography approached this issue in the mid-1990s and its main contribution was to highlight the importance of population components in the models, which, until then, had been presented mainly from a simple perspective and as secondary components. Although Brazilian demographers dedicated to environmental issues were studying primarily urban themes, they collaborated indirectly to the field by proposing new ways of thinking about relations between population and environment. This paper is based on the Brazilian Amazon Region and shows how the population has been considered in theories about changes in the uses and cover of the land. Growth related to the expansion of the agricultural frontiers has also been treated, as well as the model of the household life cycle (fertility and household composition) in the 1990s and, more recently, a focus on the migration component. For demography, the article argues how essential it is to broaden studies on demographic elements, rather than their volume and space, and its effects. For the construction of Land Change Science, the author insists on the importance of urban dynamics in research, the adoption of a methodology and the exercise of dialogue among the various fields of study, incorporating the contribution of demography more systematically.


Pensando de forma integrada la relación población-ambiente, el artículo aborda los estudios sobre dinámica poblacional y cambio en el uso y cobertura de la tierra, con enfoque en la contribución y en los desafíos de la Demografía. Aproximándose al tema hacia mediados de los años 1990, el principal aporte de la Demografía fue el de destacar la importancia de los componentes poblacionales en los modelos, antes colocados como secundarios y desde una perspectiva simple. Demógrafos brasileños dedicados a temas ambientales, aunque su propósito prioritario fuese la temática urbana, colaboraron de manera indirecta para la desenvoltura del campo, al proponer una relectura sobre relaciones población-ambiente. El artículo parte del caso de la Amazonía brasileña, mostrando cómo la población fue explorada en las teorías sobre cambios en los usos y coberturas de la tierra, pasando por el abordaje del crecimiento poblacional durante el periodo de frontera agrícola, el modelo de ciclo de vida del domicilio (fecundidad y composición del domicilio) en la década de 1990 y, más recientemente, el enfoque en el componente migratorio. Para la Demografía se señala como esencial la profundización en los elementos demográficos que abarcan más que el volumen y la inclusión del espacio y sus efectos. Para la construcción de la Ciencia del Cambio de la Tierra se destacan la incorporación de dinámicas urbanas en las investigaciones, la adopción de una metodología de múltiples escalas y el ejercicio del diálogo entre las diversas disciplinas, incorporando más sistemáticamente el aporte de la Demografía...


Subject(s)
Humans , Demography , Population Dynamics , Brazil , Conservation of Natural Resources
16.
Int J Remote Sens ; 34(16): 5953-5978, 2013.
Article in English | MEDLINE | ID: mdl-24127130

ABSTRACT

This paper provides a comparative analysis of land use and land cover (LULC) changes among three study areas with different biophysical environments in the Brazilian Amazon at multiple scales, from per-pixel, polygon, census sector, to study area. Landsat images acquired in the years of 1990/1991, 1999/2000, and 2008/2010 were used to examine LULC change trajectories with the post-classification comparison approach. A classification system composed of six classes - forest, savanna, other-vegetation (secondary succession and plantations), agro-pasture, impervious surface, and water, was designed for this study. A hierarchical-based classification method was used to classify Landsat images into thematic maps. This research shows different spatiotemporal change patterns, composition and rates among the three study areas and indicates the importance of analyzing LULC change at multiple scales. The LULC change analysis over time for entire study areas provides an overall picture of change trends, but detailed change trajectories and their spatial distributions can be better examined at a per-pixel scale. The LULC change at the polygon scale provides the information of the changes in patch sizes over time, while the LULC change at census sector scale gives new insights on how human-induced activities (e.g., urban expansion, roads, and land use history) affect LULC change patterns and rates. This research indicates the necessity to implement change detection at multiple scales for better understanding the mechanisms of LULC change patterns and rates.

17.
Environ Res Lett ; 7(4)2012.
Article in English | MEDLINE | ID: mdl-24069068

ABSTRACT

Migration necessarily precedes environmental change in the form of deforestation and soil degradation in tropical agricultural frontiers. But what environmental factors may contribute to these migration streams in the first place? Identifying environmental characteristics related to this process is crucial for understanding how environmental change and migration may form recurrent feedback loops. Further understanding this process could be useful for developing policies to reduce both environmentally induced migration from origin areas and also to palliate significant environmental change unleashed by settler deforestation in destination areas. Evidently, apprehending this holistic process cannot be approached only from the destination since this ignores environmental and other antecedents to rural out-migration. This paper presents data from surveys conducted in areas of high out-migration to the agricultural frontier in northern Guatemala. Results suggest that land scarcity and degradation in origin communities are linked to out-migration in general and to the forest frontier of northern Guatemala in particular.

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