Understanding the dynamics of native forest loss and gain is critical for biodiversity conservation and ecosystem services, especially in regions experiencing intense forest transformations. We ...quantified native forest cover dynamics on an annual basis from 1990 to 2017 in Brazil's Atlantic Forest. Despite the relative stability of native forest cover during this period (~28 Mha), the ongoing loss of older native forests, mostly on flatter terrains, have been hidden by the increasing gain of younger native forest cover, mostly on marginal lands for mechanized agriculture. Changes in native forest cover and its spatial distribution increased forest isolation in 36.4% of the landscapes. The clearance of older forests associated with the recut of 27% of younger forests has resulted in a progressive rejuvenation of the native forest cover. We highlight the need to include native forest spatiotemporal dynamics into restoration programs to better estimate their expected benefits and unexpected problems.
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Limited funding is a major barrier to implementing ambitious global restoration commitments, so reducing restoration costs is essential to upscale restoration. The lack of rigorous ...analyses about the major components and drivers of restoration costs limit the development of alternatives to reduce costs and the selection of the most cost-effective methods to achieve restoration goals. We conducted detailed restoration cost assessments for the three most widespread biomes in Brazil (Amazon, Cerrado, and Atlantic Forest) and estimated the restoration costs associated with implementing Brazil’s National Plan for Native Vegetation Recovery (12M hectares). Most surveys (60–90%) reported using the costly methods of planting seedlings or sowing seeds throughout the site, regardless of the biome. Natural regeneration and assisted regeneration approaches were an order of magnitude cheaper but were reported in <15% of projects. The vast majority of tree planting and direct seeding costs were incurred during the implementation phase, and nearly 80% of projects ended maintenance within 30 months. We estimated a price tag of US$0.7-1.2 billion per year until 2030 to implement Brazil’s restoration plan depending on the area that recovers through natural regeneration. Our results offer valuable insights for developing strategies to make restoration cheaper and to increase its cost-effectiveness for achieving diverse benefits in Brazilian ecosystems. Our survey also provides a starting point for sound assessments of restoration costs and their drivers in other biomes, which are needed to reduce the financial barriers to scaling up restoration at a global scale.
Brazil has a monitoring system to track annual forest conversion in the Amazon and most recently to monitor the Cerrado biome. However, there is still a gap of annual land use and land cover (LULC) ...information in all Brazilian biomes in the country. Existing countrywide efforts to map land use and land cover lack regularly updates and high spatial resolution time-series data to better understand historical land use and land cover dynamics, and the subsequent impacts in the country biomes. In this study, we described a novel approach and the results achieved by a multi-disciplinary network called MapBiomas to reconstruct annual land use and land cover information between 1985 and 2017 for Brazil, based on random forest applied to Landsat archive using Google Earth Engine. We mapped five major classes: forest, non-forest natural formation, farming, non-vegetated areas, and water. These classes were broken into two sub-classification levels leading to the most comprehensive and detailed mapping for the country at a 30 m pixel resolution. The average overall accuracy of the land use and land cover time-series, based on a stratified random sample of 75,000 pixel locations, was 89% ranging from 73 to 95% in the biomes. The 33 years of LULC change data series revealed that Brazil lost 71 Mha of natural vegetation, mostly to cattle ranching and agriculture activities. Pasture expanded by 46% from 1985 to 2017, and agriculture by 172%, mostly replacing old pasture fields. We also identified that 86 Mha of the converted native vegetation was undergoing some level of regrowth. Several applications of the MapBiomas dataset are underway, suggesting that reconstructing historical land use and land cover change maps is useful for advancing the science and to guide social, economic and environmental policy decision-making processes in Brazil.
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