Deforestation in the Brazilian Amazon (BA) for cattle and soybean production has significant consequences for the various aspects of the climate system. Land surface modifications due to ...deforestation directly influence surface energy and moisture availability, hence impacting rainfall patterns, air temperature and the onset of the agricultural rainy season. Here, we assess the forest loss‐related climate risks for the first and second crop seasons of the soy‐maize double cropping system in the BA. We utilized long‐term, daily, remote sensed climate data and annual land‐use maps as input for a machine learning algorithm to isolate the signal of forest loss on the climate. Our findings indicate that forest loss in the BA intensifies the risks of climate change from the local to the regional geographical scale, with the impact being more pronounced at the regional scale. Between 1999 and 2019, largely deforested regions exhibited a delay of approximately 76 days in the onset of the agricultural rainy season. These regions also experienced a 360 mm decrease in rainfall and an increase in maximum air temperature of 2.5°C. In view of these results, there are collective advantages of halting deforestation. Conservation of the Amazon Forest is vital for maintaining the early onset of the agricultural rainy season, favourable temperatures and adequate rainfall volume needed for attaining high yields in the soy‐maize double cropping system.
Significant changes were observed in rainfall and temperature in the Brazilian Amazon from 1999 to 2019. The impact of deforestation is influenced by the size of the grid cell and the level of accumulated deforestation. Increased deforestation leads to a higher probability of regional climate change, which impairs agricultural yields
Some model experiments predict a large-scale substitution of Amazon forest by savannah-like vegetation by the end of the twenty-first century. Expanding global demands for biofuels and grains, ...positive feedbacks in the Amazon forest fire regime and drought may drive a faster process of forest degradation that could lead to a near-term forest dieback. Rising worldwide demands for biofuel and meat are creating powerful new incentives for agro-industrial expansion into Amazon forest regions. Forest fires, drought and logging increase susceptibility to further burning while deforestation and smoke can inhibit rainfall, exacerbating fire risk. If sea surface temperature anomalies (such as El Niño episodes) and associated Amazon droughts of the last decade continue into the future, approximately 55% of the forests of the Amazon will be cleared, logged, damaged by drought or burned over the next 20 years, emitting 15-26 Pg of carbon to the atmosphere. Several important trends could prevent a near-term dieback. As fire-sensitive investments accumulate in the landscape, property holders use less fire and invest more in fire control. Commodity markets are demanding higher environmental performance from farmers and cattle ranchers. Protected areas have been established in the pathway of expanding agricultural frontiers. Finally, emerging carbon market incentives for reductions in deforestation could support these trends.
•We conduct statistical analyses to ascertain if environmental enforcement efforts had any impact on deforestation rates in the Brazilian Amazon.•We found that heightened enforcement in a selected ...group of targeted municipalities avoided up to 10,653km2 over the three year period of analysis (2009–2011).•This translates into 1.23×10−1PgC in avoided emissions for the 3 y period.•Most of the carbon loss and land conversion would have occurred at the expense of closed moist forests.
Reducing carbon emissions from deforestation and forest degradation now constitutes an important strategy for mitigating climate change, particularly in developing countries with large forests. Given growing concerns about global climate change, it is all the more important to identify cases in which economic growth has not sparked excessive forest clearance. We address the recent reduction of deforestation rates in the Brazilian Amazon by conducting a statistical analysis to ascertain if different levels of environmental enforcement between two groups of municipalities had any impact on this reduction. Our analysis shows that these targeted, heightened enforcement efforts avoided as much as 10,653km2 of deforestation, which translates into 1.44×10−1PgC in avoided emissions for the 3 y period. Moreover, most of the carbon loss and land conversion would have occurred at the expense of closed moist forests. Although such results are encouraging, we caution that significant challenges remain for Brazil's continued success in this regard, given recent changes in the forestry code, ongoing massive investments in hydro power generation, reductions of established protected areas, and growing demand for agricultural products.
In striking contrast to heartening events in the adjacent Amazon, Brazil's Cerrado biome has seen continued deforestation over the past decade. Though approved in 2012, no study evaluated the impacts ...of new Brazilian Forest Code (FC) revision on biodiversity and ecosystem services. Here, we report the first assessment of the likely loss and gain in biodiversity and ecosystem services expected if the FC is properly enforced across 200 million hectares of the Cerrado. We also discuss the challenges associated to compliance with the law and present opportunities for conservation. Establishing restoration programmes in private properties with currently less native vegetation than required by the FC could create habitat for 25% more threatened species than now found in these places and could also increase water security and carbon stock in 56.6 MtC. More important, trading environmental reserve quotas coupled with the strategic expansion of protected areas on private and public land could definitely rescue the Cerrado from the brink.
Spatially explicit land-use models simulate the patterns of change on the landscape in response to coupled human–ecological dynamics. As these models become more complex involving larger than ever ...data sets, the need to improve calibration techniques as well as methods that test model accuracy also increases. To this end, we developed a Genetic Algorithm tool and applied it to optimize probability maps of deforestation generated from the Weights of Evidence method for 12 case-study sites in the Brazilian Amazon. We show that the Genetic Algorithm tool, after being constrained during the reproduction process within a specified range and trend of variation of the Weights of Evidence coefficients, was able to overcome overfitting and improve validation fitness scores with acceptable computational costs. In addition to modeling deforestation, the Genetic Algorithm tool coupled with the Weights of Evidence method is flexible enough to embrace a variety of models as well as their specific fitness functions, thus offering a practical way to optimize the performance of land-use change models.
► A hybrid calibration method allows the optimization of transition probability maps. ► The hybrid method takes advantage of Weights of Evidence and Genetic Algorithm. ► We evaluated several map comparison methods to choose the best fitness function. ► The hybrid approach overcame overfitting and produced more accurate predictions. ► The GA tool offers a practical way to optimize a variety of environmental models.
The Brazilian Amazon and Cerrado biomes have been subject to strong pressure from agricultural expansion over the past two decades. A common claim is that the associated tree cover loss was partly ...driven by speculative land acquisition. In this paper, we analyze the effects of information on planned road infrastructure improvements and changes in conservation policy implementation on expectations of forest conversion. We use a unique land price dataset covering the period from 2001-2012. Based on land rent and hedonic valuation theory, we argue that forestland prices convey information on expected future land use. We decompose forestland prices into a conventional forestland rent and a speculative part related to forestland conversion and alternative land use rents. Using a fixed-effect panel, we then assess whether, where, and to what extent changes in conservation policy affect forestland prices over time. Our results confirm that forestland prices contain expectations about converting forestland to agricultural or pasture land. We also find indications that the Brazilian land market conveys information about potential conservation policy leakage and explore this conjecture descriptively using dynamic deforestation hotspot maps.
Abstract
The Brazilian government’s decision to open the Amazon biome to sugarcane expansion reignited EU concerns regarding the sustainability of Brazil’s sugar sector, hindering the ratification of ...the EU-Mercosur trade agreement. Meanwhile, in the EU, certain conventional biofuels face stricter controls, whilst uncertainty surrounding the commercialisation of more sustainable advanced-biofuels renders bioethanol as a short- to medium-term fix. This paper examines Brazil’s land-use changes and associated greenhouse gas emissions arising from an EU driven ethanol import policy and projections for other 13 biocommodities. Results suggest that Brazil’s sugarcane could satisfy growing ethanol demand and comply with EU environmental criteria, since almost all sugarcane expansion is expected to occur on long-established pasturelands in the South and Midwest. However, expansion of sugarcane is also driven by competition for viable lands with other relevant commodities, mainly soy and beef. As a result, deforestation trends in the Amazon and Cerrado biomes linked to soy and beef production could jeopardize Brazil’s contribution to the Paris agreement with an additional 1 ± 0.3 billion CO
2
eq tonnes above its First NDC target by 2030. Trade talks with a narrow focus on a single commodity could thus risk unsustainable outcomes, calling for systemic sustainability benchmarks, should the deal be ratified.
Cracking Brazil's Forest Code Soares-Filho, Britaldo; Rajão, Raoni; Macedo, Marcia ...
Science (American Association for the Advancement of Science),
04/2014, Letnik:
344, Številka:
6182
Journal Article
Recenzirano
Brazil's controversial new Forest Code grants amnesty to illegal deforesters, but creates new mechanisms for forest conservation.
Roughly 53% of Brazil's native vegetation occurs on private ...properties. Native forests and savannahs on these lands store 105 ± 21 GtCO
2
e (billion tons of CO
2
equivalents) and play a vital role in maintaining a broad range of ecosystem services (
1
). Sound management of these private landscapes is critical if global efforts to mitigate climate change are to succeed. Recent approval of controversial revisions to Brazil's Forest Code (FC)—the central piece of legislation regulating land use and management on private properties—may therefore have global consequences. Here, we quantify changes resulting from the FC revisions in terms of environmental obligations and rights granted to land-owners. We then discuss conservation opportunities arising from new policy mechanisms in the FC and challenges for its implementation.
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