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The increased availability of remote sensing products and new legislative agendas are driving a growing focus on farm‐level traceability and monitoring to tackle commodity‐driven deforestation. Here, we use data on land use change in Brazil (1985–2021) from Mapbiomas to demonstrate how analyses of the drivers of deforestation are sensitive to the scale of analysis: while pixel‐ or property‐level analyses identify proximate drivers of deforestation, analyses at larger scales (subnational regions or countries) capture more complex land use dynamics, including indirect land use change. We argue that initiatives which seek to monitor and address commodity‐driven deforestation—such as the European Union's deforestation due‐diligence regulation and the World Business Council on Sustainable Development's Greenhouse Gas Protocol—must be conscient of these wider land use dynamics. Only by measuring progress and defining success at multiple scales can initiatives for sustainable commodity sourcing create the right mix of incentives for addressing deforestation. [ABSTRACT FROM AUTHOR]

Large-scale land use/land cover changes have occurred in Mato Grosso State (hereafter MT), Brazil, following the introduction of extensive mechanized agriculture and pastoral activities since the 1980s. Author investigated what kind of agro-pastoral activities which are both cattle ranching and top five crops (soybean, sugarcane, corn, cotton and rice) that are closely related to land use change on lands experiencing conversion land use change (such as deforestation and the increase in deeply anthropogenically influenced areas) at each municipal district in MT. Then, this study identifies the volume of exports including contribution ratio by municipal districts where land use changed due to agro-pastoral activities. The patterns of vegetation change indicated that cattle ranching, corn, cotton, rice croplands in the northwest, and soybean and sugarcane fields in the central areas are the main contributors to deforestation. It is shown that land use change due to soybean or corn cultivation occurs mainly in the west and the southeast, respectively. Corn cultivation is associated with a greater increase in anthropogenically influenced areas than soybean cultivation. The municipal districts that export each agro-pastoral product with land use change are limited. Exports of soybeans, corn, and cotton in the municipal districts associated with deforestation had increased dramatically after experienced land use change. For example, Sapezal, which has experienced deforestation, was the only municipal district associated with export of corn to only Switzerland. Since 2007, the number of export partners has increased to 56 countries with the export volume increased 2300 times. These findings highlight the overall non-sustainability of environmental resource development activities in MT. [ABSTRACT FROM AUTHOR]

The conversion of native forest into agricultural land, which is common in many parts of the world, poses important questions regarding soil degradation, demanding further efforts to better understand the effect of land use change on soil functions. With the advent of 3D computed tomography techniques and computing power, new methods are becoming available to address this question. In this direction, in the current work we implement a modification of the Fisher–Shannon method, borrowed from information theory, to quantify the complexity of twelve 3D CT soil samples from a sugarcane plantation and twelve samples from a nearby native Atlantic forest in northeastern Brazil. The distinction found between the samples from the sugar plantation and the Atlantic forest site is quite pronounced. The results at the level of 91.7% accuracy were obtained considering the complexity in the Fisher–Shannon plane. Atlantic forest samples are found to be generally more complex than those from the sugar plantation. [ABSTRACT FROM AUTHOR]

Worldwide, important biodiversity hotspots have been threatened by land use change, placing several species at risk. Some gaps in environmental licensing system represent challenges for the nature conservation and should be further investigated. Far beyond conservation strategies, the process of legalizing land use of some countries urgently needs to be reviewed, especially in places that host biological megadiversity, such as the Atlantic Forest, southeastern Brazil. This is the first multiple case study that evaluates the use of ecological descriptors in environmental impact assessment involving vegetation in different successional stages of the Atlantic Forest. The methodology was divided into two steps, i) the selection of the reports in a public environmental agency of São Paulo State and ii) the assessment of ecological criteria inherent to the vegetation survey. This study verified a scarcity of reports presenting adequate ecological descriptors according to the law in their reports, which would improve the assessment of the natural environmental framework. Although ecological parameters appear in some reports, they do not show relevant information, even though for the characterization of the succession stages of the forest fragments, thus hiding important information and leaving aside a parameter that should be essential in the approval/disapproval of reports. Thus, we suggest that the data presented and accepted by the Public Environmental Agency of São Paulo, Brazil, did not adequately characterize the stages of ecological succession in the studied areas, thus putting some ecological patterns and processes at risk. This issue must be urgently reviewed so reports should show the real threats for biodiversity. • Ecological descriptors are underutilized in EIA in Brazil • Biodiversity is threatened by the lack of rigor in EIS and EIR • Environmental agencies must be more rigorous in the ecological criteria presented in EIA • Ecological succession must be carefully evaluated in EIA [ABSTRACT FROM AUTHOR]

Voluntary land registries can affect land use by facilitating both the public's ability to monitor land use and farmers' access to credit. We estimate the impacts of participation in a land registry on the conversion of natural vegetation to agricultural land use by examining the impacts of the rural environmental registry (CAR) in Brazil, using a dynamic land use model. We show that although participation in the CAR does not significantly affect crop area, it does influence pasture expansion, with variation by farm size and environmental compliance level. Our results provide insights for agricultural land‐use policies by illuminating how the intended environmental objectives of land registry programs might be undermined by credit policies. [ABSTRACT FROM AUTHOR]

Aim: To explore spatiotemporal changes in Hyacinth Macaw Anodorhynchus hyacinthinus distribution and the impacts of land use change over 25 years, across its vast range in central/eastern South America. Location: Brazil, Bolivia and Paraguay, South America, covering almost 3 million km2. Methods: We use a novel, multi‐temporal species distribution model, to combine both year‐specific occurrence records and land use/cover data in a single model that is subsequently projected over a land cover time series. We investigate changes in geographic range over 25 years and potential drivers of range extent at multiple spatial scales (10 and 30 km) and time‐lags (current and 10 years previously). We also assess protected area coverage and impacts from degazettement within the remaining range and highlight priority areas to search for undiscovered populations. Results: The modelled range of the species increased by 75,000 km2 to over 500,000 km2 between 1995 and 2019, during which period agriculture and pasture increased by 600,000 km2 within the species' extent of occurrence. Habitat suitability was influenced most strongly by distribution of palms, forest cover and changes in pasture over 10 years and usually by predictors measured at larger spatial scales. Just 8% of the macaw's modelled range falls within protected areas, and more than 20,500 km2 of protected areas overlapping with the range have been degazetted in the last 40 years. We highlight key areas to search for undiscovered populations in under‐sampled and remote areas, especially led by community citizen science initiatives involving indigenous groups and protected area staff. Main conclusions: Novel modelling methods, combining multi‐temporal occurrence records and land cover data, appropriate for small sample sizes per year, have revealed habitat dynamics and changes to the range of this threatened species over 25 years. The method may have wide applicability for a range of species, including elusive and poorly studied species. [ABSTRACT FROM AUTHOR]

Aim: To provide novel evidence on the average impact of climate and land use changes on habitat suitability for tropical plants and to test previous conclusions on the relative importance of these two drivers in shaping future availability of habitat for tropical plant species. Location: Brazil's Atlantic Forest domain. Time period: Plant occurrences recorded between 1960 and 2014. Baseline climate from 1960 to 2000 and land use from 2015. Projected scenarios of climate for 2041–2060 and land use for 2050. Major taxa studied: Angiosperms. Methods: We modelled the habitat suitability of 2,232 species of angiosperms from the Atlantic Forest domain, endemic to Brazil, and estimated how future climate and land use may affect species‐level habitat suitability under a moderate and a business‐as‐usual scenario for the year 2050. Results: Our results suggest that climate change alone will, surprisingly, have only a modest negative impact on the mean habitat suitability, decreasing it by 2% (median = −5 to −7%, variation associated with scenarios). Land use change alone had a more consistent negative impact on habitat suitability, causing mean and median reductions of 4 to 6%. When the effects of climate and land use are combined, the mean habitat suitability was reduced by 4% (median = −9 to −11%). Main conclusions: The combined impacts of climate and land use changes were substantial, although smaller than expected. Habitat suitability decreased for most species, but it increased substantially for some species, suggesting that the distribution of impacts across species is markedly right skewed. The impacts were typically detrimental to small‐ranged species and neutral or beneficial to widespread species. Land use change rather than climate change will likely cause more losses to the habitat of Atlantic Forest plant species within the next several decades. [ABSTRACT FROM AUTHOR]

The desertification process directly influences agricultural production and the maintenance of terrestrial life. Despite being an important agricultural centre, Brazil's semi-arid region is experiencing significant desertification. However, the relationship between land management and climate in this process is still poorly understood. This research was conducted in areas predominantly covered by the Caatinga Formation (62.2%), as well as agropastoral and pasture areas (29.9%). Our primary objective was to assess the land use change trajectories and land occupation patterns in the region while also analysing how vegetation and precipitation temporal patterns have changed from 1985 to 2019. The trends in vegetation and precipitation were evaluated using the Mann-Kendall test. Land use and occupation patterns were analysed using segmented regression and Monte Carlo simulation for future forecasting in the period 2020–240 under different scenarios (pessimistic, conservative, and optimistic). The Mann-Kendall test indicated that the precipitation trends were not statistically significant. However, the normalized vegetation index (NDVI) exhibited a significant trend in areas near the São Francisco River, an important agricultural area. Land use and occupation showed breakpoints from 1990 onwards for most classes. Monte Carlo simulations demonstrated that the Caatinga Formation will likely to remain the predominant vegetation class in the region for the next 21 years in all predicted scenarios. Agropastoral and pasture classes are projected to increase by 8% and 3%, respectively, while the area covered by native vegetation is expected to decrease by 7.5%. Furthermore, the predictions showed a decline in the rivers and lakes class, which may result in significant economic and social problems. Our findings contribute to a better understanding of the impacts of land use change in the Brazilian semi-arid region and provide science-based information for environmental public policies. Representation of the change in land use caused by the removal of native vegetation cover for agricultural use incorrectly, resulting in soil degradation, with salinization as the main consequence. [Display omitted] • Land use changes and trends of vegetation and precipitation were analysed. • Land use scenarios were forecasted for the next 21 years (2020–2040). • A significant positive NDVI trend was observed. • Caatinga Formation will remain the predominant land cover in the area. • Agropastoral will expand for the next 21 years, surpassing the pasture cover. [ABSTRACT FROM AUTHOR]

Aim To propose and compare priority sites for conservation and restoration of woody plants under diverse climate and land use scenarios, considering socio-economic costs, presence of protected areas and distribution of forest remnants. Location The Atlantic Forest Biodiversity Hotspot, Brazil. Methods We used ecological niche modelling to estimate geographical distributions for 2,255 species under current and future climate scenarios, which we analysed in relation to spatially explicit land use projections, maps of forest remnants derived from remote sensing and socio-economic variables for each municipality within the Atlantic Forest region. We identified spatial priorities that complement the current network of protected areas under three different prioritization scenarios: (1) conservation of existing forest remnants only; (2) conservation of remnants followed by restoration of degraded habitat; and (3) unconstrained actions, in which management location is not defined a priori. We compared our results under different levels of land protection, with targets of 10%, 17% and 20% of the Atlantic Forest extent. Results Current forest remnants cover only 12% of the Atlantic Forest, so targets of 17% and 20% were achieved only through active restoration. Targets of 17% and 20% captured most species and represented on average 26%-34% of species' distributions. The spatial pattern of degraded habitats negatively affected representation of biodiversity and implied higher costs and reduced efficiency of planning. We did not observe major differences between conservation prioritizations based on contrasting climate change scenarios. Main conclusions Protection of forest remnants alone will not suffice to safeguard woody plant species under climate and land use changes; therefore, restoration actions are urgently needed in the Atlantic Forest. With integrated management actions and multicriterion nationwide planning, reaching the 17% of land protection of Aichi biodiversity targets will constitute an important step towards protecting Atlantic Forest biodiversity. [ABSTRACT FROM AUTHOR]

Since 2000, soybean production has gained increasing importance in Brazil, particularly in Southern Amazonia and the state of Mato Grosso, the largest producer in the country. This expansion has taken place through cropland extensification into natural ecosystems in the Amazon (tropical forest) and Cerrado (savanna) biomes with land transformation and occupation activity well documented by remote sensing. Guidelines from the UNEP/SETAC Life Cycle Initiative now allow for impact assessment of land transformation and occupation within a Life Cycle Assessment (LCA) to estimate potential impacts to biodiversity and ecosystem services. In this study, we apply these guidelines to soybean produced in 2010 in order to complement more traditional soybean LCAs with mid- and end-point impact assessment on biodiversity, erosion potential, water purification, groundwater recharge, biotic production and climate regulation potential in each of the Amazon and Cerrado biomes. In addition to providing regionalized characterization factors of land transformation and occupation in both Mato Grosso biomes, we estimate that one tonne of soybean produced in 2010 in the Amazon had greater impacts than when produced in the Cerrado. For the Amazon, total land transformation and occupation damage was estimated at $ 532 ton −1 and $ 260 ton −1 respectively, with estimates of $ 231 ton −1 and $ 153 ton −1 for the Cerrado. The largest contributors to these damage estimates came from the change in mechanical filtration properties of the soil followed by the land's climate regulation and biotic production potentials. The impact allocation to pasture as a transitional landscape in the establishment of cropland onto natural ecosystems diminished the soybean contribution through allocation of pasture to the beef production system, further adding to the land sparing argument for future cropland expansion in the region. [ABSTRACT FROM AUTHOR]

The Brazilian Cerrado area is in rapid decline because of the expansion of modern agriculture. In this study, we used extensive field data and a 30-year chronosequence of Landsat images (1980-2010) to assess the effects of time since conversion of Cerrado into agriculture upon soil chemical attributes and soybean/corn yield in the Alto do Rio Verde watershed. We determined the rates of vegetation conversion into agriculture, the agricultural land use time since conversion, and the temporal changes in topsoil (0-20 cm soil depth) and subsurface (20-40 cm) chemical attributes of the soils. In addition, we investigated possible associations between fertilization/over-fertilization and land use history detected from the satellites. The results showed that 61.8% of the native vegetation in the Alto do Rio Verde watershed was already converted into agriculture with 31% of soils being used in agriculture for more than 30 years. While other fertilizers in cultivated soils (e.g., Ca, Mg, and P) have been compensated over time by soil management practices to keep crop yield high, large reductions in C (38%) and N (29%) were observed in old cultivated areas. Furthermore, soybean and cornfields having more than 10 years of farming presented higher values of P and Mg than the ideal levels necessary for plant development. Therefore, increased risks of over-fertilization of the soils and environmental contamination with these macronutrients were associated with soybean and cornfields having more than 10 years of farming, especially those with more than 30 years of agricultural land use. [ABSTRACT FROM AUTHOR]

In Central Brazil, over one million square kilometers of native savanna vegetation known as Cerrado have been cleared and converted to farmland over the past forty years. A factorial experiment was designed to assess the effects of land use, litter type, soil organisms and season on litter decay in the prevailing natural and agricultural systems ( i.e. Cerrado remnants, grasslands and soybean croplands) in Mato Grosso. Decay rates were estimated by using the litterbag method. Two different mesh sizes were used to evaluate the effects of soil macro- and mesofauna (coarse mesh; 5 mm) and of soil microorganisms (fine; 20 μm). The original litter found in each land use area (Cerrado leaf-litter, Brachiaria -grass or soybean residues) was used to estimate the decay of in situ litter; a standard substrate (maize litter) was employed to evaluate the effect of the environment. Finally, the experiment was carried out during a dry and a rainy season to differentiate the effect of the other factors from the seasonal effect. We found that: (1) the effects of land use and management practice were only significant in the dry season; (2) decomposability of litter was not predicted by the initial C:N ratio of the litter types; (3) soil fauna contributed to the litter breakdown with 13–57%; (4) decay rates were overall higher in the rainy season; (5) all evaluated factors (in following order: season > soil organisms > litter type > land use) and their interactions explained about 70% of the variance in the decay rates in the study area. Change in land use affected litter decay mainly through a shift in the litter quality; the introduced plant species produced highly decomposable litters. [ABSTRACT FROM AUTHOR]

In the past decades, Brazil made important progress in the conservation of forest ecosystems. Non-forest ecosystems ( NFE), in contrast, have been neglected, even though they cover large parts of the country and have biodiversity levels comparable to forests. To avoid losing much of its biodiversity and ecosystem services, conservation and sustainable land use policies in Brazil need to be extended to NFE. A strategy for conservation of Brazil's NFE should encompass the following elements: (1) creation of new large protected areas in NFE; (2) enforcement of legal restrictions of land use; (3) extension of subsidy programs and governance commitments to NFE; (4) improvement of ecosystem management and sustainable use in NFE; and (5) improvement of monitoring of land use change in NFE. If Brazil managed to extend its conservation successes to NFE, it not only would contribute significantly to conservation of its biodiversity, but also could take the lead in conservation of NFE world-wide. [ABSTRACT FROM AUTHOR]

Forest ecosystems are a sink of atmospheric mercury, trapping the metal in the canopy, and storing it in the forest floor after litter fall. Fire liberates a portion of this mercury; however, little is known about the long-term release of mercury post deforestation. We conducted two large-scale experiments to study this phenomenon. In upstate New York, gaseous mercury emissions from soil were monitored continually using a Teflon dynamic surface flux chamber for two-weeks before and after cutting of the canopy on the edge of a deciduous forest. In Brazil, gaseous mercury emissions from soil were monitored in an intact Ombrophilous Open forest and an adjacent field site both before and after the field site was cleared by burning. In the intact forest, gaseous mercury emissions from soil averaged −0.73 ± 1.84 ng m −2 h −1 (24-h monitoring) at the New York site, and 0.33 ± 0.09 ng m −2 h −1 (daytime-only) at the Brazil site. After deforestation, gaseous mercury emissions from soil averaged 9.13 ± 2.08 ng m −2 h −1 in New York and 21.2 ± 0.35 ng m −2 h −1 at the Brazil site prior to burning. Gaseous mercury emissions averaged 74.9 ± 0.73 ng m −2 h −1 after burning of the cut forest in Brazil. Extrapolating our data, measured over several weeks to months, to a full year period, deforested soil is estimated to release an additional 2.30 g ha −1 yr −1 of gaseous mercury to the atmosphere in the Brazilian experiment and 0.41 g ha −1 yr −1 in the New York experiment. In Brazil, this represents an additional 50% of the mercury load released during the fire itself. [ABSTRACT FROM AUTHOR]

Land use changes have resulted in large environmental impacts, and in agricultural landscapes sometimes only forest fragments remain. Riparian forest remnants can positively influence stream water quality, and serve as refuges for aquatic species. We evaluated whether the presence of a riparian forest remnant influenced the structure and composition of macroinvertebrate communities in a rural stream in southeastern Brazil. We sampled three reaches upstream (within abandoned sugarcane cultivation) and nine downstream the remnant edge, until 600 m inside the forested area, using leaf litter bags. The abundances of Elmidae, Chironomidae, and total macroinvertebrates increased along the forest remnant, whereas the abundance of Baetidae, proportion of Ephemeroptera, Plecoptera, and Trichoptera (EPT), rarefied taxonomic richness, and diversity decreased. Taxon richness and EPT abundance did not vary along the forest remnant. Increases in Chironomidae and total abundance within the forest remnant can be related to moderate increases in nutrient concentrations, or to the availability of high quality leaf litter patches. Forest remnants can influence macroinvertebrate communities, although variation both in temperate and tropical studies can be related to local agricultural practices and land use at the watershed scale. Forest remnants are important in maintaining stream water quality in rural landscapes, and deserve attention in watershed management projects. [ABSTRACT FROM AUTHOR]

Abstract: In order to analyse the impact of land use change, it is particularly important to know how organisms use resources distributed across a heterogeneous landscape. The main objective of this study is to analyse the potential impact of land use change on bird and mammal fauna, by using a coupled model approach. The CLUE (Conversion of Land Use and its Effects) model has been applied to obtain the spatial pattern of land use change for a scenario with soybean expansion in the Cerrado of Maranhão State in Brazil. These land use change maps were used as the input for the LEDESS (Landscape Ecological Decision and Evaluation Support System) model to evaluate the impact of habitat fragmentation on mammal and bird species. The scenarios demonstrated that high quality habitat for all studied species will be lost in the future when current trends in agricultural expansion continue, but these changes will have species-specific impacts. The most relevant ecological impact under the explored scenarios was habitat fragmentation expressed by the increase the number of habitat clusters. The coupled model approach of LEDESS and CLUE made it possible to project the spatial impact of soybean expansion on habitat dynamics in the studied region. This model approach can help to design effective ecological infrastructure to facilitate species survival and to implement an effective habitat network in the Balsas region. [Copyright &y& Elsevier]

We present a local-scale case study in the Rio Juma Settlement Project (RJSP) in Apuí, a deforestation hotspot in the southern portion of Brazil's state of Amazonas. We analyze land accumulation and land use strategies of households with a view to elucidating how their strategies are shaping deforestation. More than 76% of the household sample was from southern Brazil, and around 72% of them migrated to older expansion frontiers before reaching Apuí. The percentage of properties with legal land titles was up to five times less while land accumulation was much greater than reported for other settlement projects in Brazil. Land use change followed different patterns depending on whether the lot had been obtained with 100% forest cover or with inherited land use. Regression-tree analysis showed that the size of the cattle herd and the total area of the property do not always explain the area deforested, nor is the size of the deforested area necessarily related to productive activities. Lack of income obtained from livestock indicated that at least 30% of the cases studied were related to the speculative nature of land acquisition and deforestation. Increasing consolidation of land in larger, more highly capitalized ranches indicates the potential for high rates of deforestation in the future, even when the profitability of livestock is questionable. [ABSTRACT FROM AUTHOR]

Abstract: Brazil is experiencing a surge in planting of sugar cane crops driven by internal markets and external policy drivers for biofuels. The current expectation is for the expansion of these crops to continue. This creates concern over the extent to which the full implications of large scale land use change are currently being considered by decision-makers. Using the State of São Paulo as a case study (as it accounts for the majority of sugar cane grown in Brazil), a comparison was made of the impacts identified in Environmental Impact Statements (EISs) and Preliminary Environmental Reports (PERs), which have to be submitted for approval of most new sugar cane activities, with significant impacts known to be associated with sugar cane activities derived from literature review. The results from a review of 32 EISs and PERs (30% of the population) indicated that whilst some impacts were well covered by the sample (water and soil pollution, and air emissions) energy balance and Green House Gas emissions and food security had very limited consideration, and water resources, residues, labour conditions and social responsibility were only partially covered. Environmental Impact Assessment is constrained by its environmental advocacy role and its application to the project level only. This study highlights its limitations in the context of assessment of land use change which demands more strategic consideration. [Copyright &y& Elsevier]

Maintenance of soil quality is a key component of agriculture sustainability and a main goal of most farmers, environmentalists and government policymakers. However, as there are no parameters or methods to evaluate soil quality directly, some attributes of relevant soil functions are taken as indicators; lately, an increase in the use of soil microbial parameters has occurred, and their viability as indicators of proper land use has been highlighted. In this study we performed a meta-analysis of the response ratios of several microbial and chemical parameters to soil disturbance by different land uses in the Brazilian biomes. The studies included native forests, pastures and perennial and annual cropping systems. The introduction of agricultural practices in all biomes covered previously with natural vegetation profoundly affected microbial biomass-C (MB-C)-with an overall decrease of 31%. Annual crops most severely reduced microbial biomass and soil organic C, with an average decrease of 53% in the MB-C. In addition, the MB-C/TSOC (total soil organic carbon) ratio was significantly decreased with the transformation of forests to perennial plantation (25%), pastures (26%), and annual cropping (20%). However, each biome reacted differently to soil disturbance, i.e., decreases in MB-C followed the order of Cerrado>Amazon>Caatinga>Atlantic Forest. In addition, the Cerrado appeared to have the most fragile soil ecosystem because of lower MB-C/TSOC and higher qCO. Unfortunately, the Cerrado and the Amazon, demonstrated by our study as the most fragile biomes, have been subjected to the highest agronomic pressure. The results reported here may help to infer the best land-use strategies to improve soil quality and achieve agriculture sustainability. The approach can also be very useful to monitor soil quality in other tropical and subtropical biomes. [ABSTRACT FROM AUTHOR]

This study's overarching aim is to establish the areal extent and characteristics of the rapid sugarcane expansion and land use change in São Paulo state (Brazil) as a result of an increase in the demand for ethanol, using Landsat type remotely sensed data. In 2003 flex fuel automobiles started to enter the Brazilian consumer market causing a dramatic expansion of sugarcane areas from 2.57 million ha in 2003 to 4.45 million ha in 2008. Almost all the land use change, for the sugarcane expansion of crop year 2008/09, occurred on pasture and annual crop land, being equally distributed on each. It was also observed that during the 2008 harvest season, the burned sugarcane area was reduced to 50% of the total harvested area in response to a protocol that aims to cease sugarcane straw burning practice by 2014 for mechanized areas. This study indicates that remote sensing images have efficiently evaluated important characteristics of the sugarcane cultivation dynamic providing quantitative results that are relevant to the debate of sustainable ethanol production from sugarcane in Brazil. [ABSTRACT FROM AUTHOR]

Abstract: This work reports on the effect of land use change on Hg distribution in Amazon soils. It provides a comparison among Hg concentrations and distribution along soil profiles under different land use categories; primary tropical forest, slashed forest prior to burning, a 1-year silviculture plot planted after 4 years of forest removal and a 5-year-old pasture plot. Mercury concentrations were highest in deeper (60–80cm) layers in all four plots. Forest soils showed the highest Hg concentrations, ranging from 128ngg−1 at the soil surface to 150ngg−1 at 60–80cm of depth. Lower concentrations were found in pasture soils, ranging from 69ngg−1 at the topsoil to 135ngg−1 at 60–80cm of depth. Slashed and silviculture soils showed intermediate concentrations. Differences among plots of different soil-use categories decreased with soil depth, being non-significant below 60cm of depth. Mercury burdens were only statistically significantly different between pasture and forest soils at the topsoil, due to the large variability of concentrations. Consequently, estimated Hg losses were only significant between these two land use categories, and only for the surface layers. Estimated Hg loss due to forest conversion to pasture ranged from 8.5mgm−2 to 18.5mgm−2, for the first 20cm of the soil profile. Mercury loss was comparable to loss rates estimated for other Amazon sites and seems to be directly related to Hg concentrations present in soils. [Copyright &y& Elsevier]

This article examines transformations associated with changes in resource use and land cover dynamics in the community of São Manoel, Maranhão state, in the eastern Brazilian Amazon. The shifting cultivator peasants in São Manoel integrate swidden fields for annual cropping, the extraction of babassu palm products, and pastures for cattle ranching. Since the early twentieth century, predominant vegetative cover patterns have been altered from species-rich mature forests to secondary succession with babassu dominant to pasture or swidden fields containing palm stands of various densities. A grounded political ecology of resource use in the area suggests that management strategies and the resulting land cover dynamics integrate site-specific decisions of peasant producers. I discuss the trajectory of production strategies in São Manoel since the establishment of the community in the 1920s, and identify the multiple dimensions affecting resource use and environmental outcomes, with an emphasis on the period following land struggles and the recovery of peasant tenure rights in the mid-1980s. The analysis indicates that socionatural trajectories that optimize resource use and address the socioeconomic needs of the community include the maintenance of palm/pastures associations. [ABSTRACT FROM AUTHOR]

Western Bahia is a critical region in Brazil's recent expansion of agricultural output. Its outstanding increase in production is associated with strong growth in cropland area and irrigation. Here we present analyses of Western Bahian historical changes in land use, including irrigated area, and suitability for future agricultural expansion that respects permanent protection areas and the limits established by the Brazilian Forest Code in the Cerrado biome. For this purpose, we developed a land use and land cover classification database using a random forest classifier and Landsat images. A spatial multicriteria decision analysis to evaluate land suitability was performed by combining this database with precipitation and slope data. We demonstrate that between 1990 and 2020, the region's total agricultural area increased by 3.17 Mha and the irrigated area increased by 193,480 ha. Throughout the region, the transition between the different classes of land use and land cover followed different pathways and was strongly influenced by land suitability and also appears to be influenced by Brazil's new Forest Code of 2012. We conclude that even if conservation restrictions are considered, agricultural area could nearly double in the region, with expansion possible mostly in areas we classify as moderately suitable for agriculture, which are subject to climate hazards when used for rainfed crops but are otherwise fine for pastures and irrigated croplands. [ABSTRACT FROM AUTHOR]

The Cerrado biome is Brazil's breadbasket and a major provider of ecosystem services, though these dual roles are increasingly at odds, in part because there are few mechanisms to protect remaining vegetation from large‐scale agricultural expansion. We assessed Cerrado conversion to soy using over 580,000 property boundaries, covering 77% of the biome that is eligible for commercial land use, and using microwatersheds, to cover 100% of eligible areas. Soy expansion accounted for 22% of conversion during 2003–14. Only 15% of clearing exceeded restrictions on private properties under the Forest Code (FC). However, 51% of soy farms have violated the FC, five times the rate of other farms. As a leading cause of both Cerrado conversion and FC violations, the soy sector has environmental and economic incentives to shift production to already cleared land. We used suitability maps to identify potential pathways for soy expansion across both old and new cropland frontiers. [ABSTRACT FROM AUTHOR]

Background: Hantavirus disease in humans is rare but frequently lethal in the Neotropics. Several abundant and widely distributed Sigmodontinae rodents are the primary hosts of Orthohantavirus and, in combination with other factors, these rodents can shape hantavirus disease. Here, we assessed the influence of host diversity, climate, social vulnerability and land use change on the risk of hantavirus disease in Brazil over 24 years. Methods: Landscape variables (native forest, forestry, sugarcane, maize and pasture), climate (temperature and precipitation), and host biodiversity (derived through niche models) were used in spatiotemporal models, using the 5570 Brazilian municipalities as units of analysis. Results: Amounts of native forest and sugarcane, combined with temperature, were the most important factors influencing the increase of disease risk. Population at risk (rural workers) and rodent host diversity also had a positive effect on disease risk. Conclusions: Land use change—especially the conversion of native areas to sugarcane fields—can have a significant impact on hantavirus disease risk, likely by promoting the interaction between the people and the infected rodents. Our results demonstrate the importance of understanding the interactions between landscape change, rodent diversity, and hantavirus disease incidence, and suggest that land use policy should consider disease risk. Meanwhile, our risk map can be used to help allocate preventive measures to avoid disease. [ABSTRACT FROM AUTHOR]

Assessing the persistent impacts of fragmentation on aboveground structure of tropical forests is essential to understanding the consequences of land use change for carbon storage and other ecosystem functions. We investigated the influence of edge distance and fragment size on canopy structure, aboveground woody biomass (AGB), and AGB turnover in the Biological Dynamics of Forest Fragments Project (BDFFP) in central Amazon, Brazil, after 22+ yr of fragment isolation, by combining canopy variables collected with portable canopy profiling lidar and airborne laser scanning surveys with long‐term forest inventories. Forest height decreased by 30% at edges of large fragments (>10 ha) and interiors of small fragments (<3 ha). In larger fragments, canopy height was reduced up to 40 m from edges. Leaf area density profiles differed near edges: the density of understory vegetation was higher and midstory vegetation lower, consistent with canopy reorganization via increased regeneration of pioneers following post‐fragmentation mortality of large trees. However, canopy openness and leaf area index remained similar to control plots throughout fragments, while canopy spatial heterogeneity was generally lower at edges. AGB stocks and fluxes were positively related to canopy height and negatively related to spatial heterogeneity. Other forest structure variables typically used to assess the ecological impacts of fragmentation (basal area, density of individuals, and density of pioneer trees) were also related to lidar‐derived canopy surface variables. Canopy reorganization through the replacement of edge‐sensitive species by disturbance‐tolerant ones may have mitigated the biomass loss effects due to fragmentation observed in the earlier years of BDFFP. Lidar technology offered novel insights and observational scales for analysis of the ecological impacts of fragmentation on forest structure and function, specifically aboveground biomass storage. [ABSTRACT FROM AUTHOR]

An important unsolved question in hydrology science is the consequence of the Eucalyptus afforestation on groundwater recharge. Here, we assessed recharge estimates before and after converting pasture cover to Eucalyptus plantation. Groundwater levels, recharge, rainfall (P) and actual evapotranspiration (ET) were evaluated from 2004 through 2016 over an outcrop area of the Guarani Aquifer System (GAS) in the southeastern Brazil. Recharge was estimated using the water-table fluctuation method. We observed a decrease of 100 mm/year in groundwater levels after land use changed from pasture to Eucalyptus. The average recharge decreased from 407 mm/year (27% of mean P) to 194 mm/year (13% of mean P) after land use change over the study area. We found a recharge decrease of 19% in 2012 and 58% in 2013 under similar annual rainfall in comparison with the long-term mean recharge (from 2004 to 2016). Our results indicated that the high values of ET observed in Eucalyptus plantation decreases water availability for recharge. Therefore, our findings are important to agencies for decision-making in water resources regarding the management of land cover and land use. [ABSTRACT FROM AUTHOR]