Resumo -O objetivo deste trabalho foi avaliar o potencial de mitigação de óxido nitroso (N 2 O) em sistema de integração lavoura-pecuária-floresta (ILPF), em comparação ao monocultivo, e identificar os principais fatores que regulam as emissões deste gás. O experimento foi realizado em Sinop, MT, entre as safras 2012/2013 e 2013/2014, e avaliou os seguintes tratamentos: floresta, lavoura e pastagem, além do ILPF. Durante a realização do experimento, não houve presença de bovinos nas áreas com pastagem. Amostras de óxido nitroso foram coletadas semanalmente, com uso de câmaras estáticas, modelo topo-base. As concentrações do gás foram determinadas por meio de cromatografia gasosa. A precipitação pluvial e a disponibilidade de N foram os principais fatores reguladores das emissões de N 2 O. O sistema de ILPF apresenta potencial promissor para mitigar as emissões de N 2 O, com emissão acumulada de 0,367 kg ha -1 de N, em comparação a de 1,401 kg ha -1 emitidas pela lavoura; de 0,298 kg ha -1 , pela pastagem; e de 0,165 kg ha -1 , pela floresta.Termos para indexação: gases de efeito estufa, mudança do clima, sistemas integrados de produção. Nitrous oxide fluxes in an integrated crop-livestock-forestry systemAbstract -The objective of this work was to evaluate the mitigation potential of nitrous oxide in an integrated crop-livestock-forestry system (ICLF), compared with monocultures, and to identify the main factors that regulate the emissions of this gas. The experiment was conducted in the municipality of Sinop, in the state of Mato Grosso, Brazil, between the 2012/2013 and 2013/2014 crop seasons, with the evaluation of the following treatments: forest, crop and pasture, besides ICLF. During the experiment, no cattle were present in the pasture areas. Nitrous oxide samples were collected weekly using top-down static chambers. Gas concentrations were determined with gas chromatography. Rainfall and N availability were main factors regulating N 2 O emissions. The ICLF system has promising potential to mitigate N 2 O emissions, with 0.367 kg ha -1 N accumulated emission, compared with 1.401 kg ha -1 from cropland, 0.298 kg ha -1 from pasture, and 0.165 kg ha -1 from forest.

The Amazon and the Atlantic Forest are Brazilian biomes that suffered an intense land use and land cover change, marked by the loss of native forest and expansion of agriculture and livestock. This article aims to analyze land use and land cover change history and to propose a sustainable alternative for agriculture and livestock as an opportunity for rural development in these biomes. The statistics of the platform from the Annual Mapping Project for Land Use and Land Cover in Brazil (MapBiomas) were used in an annual historical series from 1985 to 2020. The analysis of land use and land cover changes indicates that the Amazon native forest was reduced by 44.53 million hectares (Mha), while pasture, agriculture and planted forest increased by 38.10, 6.06 and 0.26 Mha, respectively, over the 35 years (1985 to 2020). In the Atlantic Forest, for the same period, forest and pasture reduced by 0.99 and 11.53 Mha, respectively, while agriculture expanded by 8.06 Mha and planted forest by 2.99 Mha. Sustainable land use strategies, such as the Integration Crop-Livestock-Forest (ICLF), can support the increase in agricultural production while recovering and preserving the environment. Policies and programs should consider regional particularities and barriers for more significant adoption of this strategy.

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The Amazon and the Atlantic Forest are Brazilian biomes that have undergone intense land use and cover changes, marked by the loss of native forest and the expansion of agriculture and livestock. These are areas with potential use for intensification based on low-carbon technologies, but this change is still taking place slowly. Some factors need to be identified to guide promising solutions for this issue. Aiming at this, this study aimed to identify the land use and land cover in a historical series of 35 years in the Amazon and Atlantic Forest and describe the patterns of sustainable land use by producers who use this technique in the Amazon, identifying their characteristics and perceptions regarding the change developed in the farm. The statistics of the platform from the Annual Mapping Project for Land Use and Land Cover in Brazil (MapBiomas) were used in an annual historical series from 1985 to 2020. The analysis of land use and land cover changes indicates that the native forest of the Amazon was reduced by 44.53 million hectares (Mha), while pastures, agriculture and planted forest increased by 38.10, 6.06 and 0.26 Mha, respectively, over the 35 years. In the Atlantic Forest, for the same period, forest and pasture reduced by 0.99 and 11.53 Mha, respectively, while agriculture expanded by 8.06 Mha and planted forest by 2.99 Mha. Sustainable land use strategies, such as Integrated Crop-Livestock-Forest (ICLF) or Agroforestry Systems (AFS), can support increased agricultural production while recovering and preserving the environment. In view of this, we identified in the Amazon, the pattern of land use by farmers who adopt sustainable technologies, considering AFS and managed pasture monoculture (MP). The results were generated through interviews and analysis of qualitative and quantitative research that allowed the evaluation of producers in three states in the Amazon (Mato Grosso, Pará and Rondônia). In general, farmers in the Amazon are still risk averse and mainly implement MP. But when assessing the states in isolation, we realize that the producers in Pará and Rondônia are more approachable when it comes to moving to a diversified system. We did not find many differences in the profile of these producers, but we noticed that pasture adopters always have areas of larger properties and generally develop livestock as their main economic activity. On the other hand, AFS producers have smaller areas of property, conserve more forest and may have agriculture as the main activity of the property. Regional and local fitness, producer tradition and technology transfer can influence the decision of the adopted technology. There are great opportunities to improve agricultural and livestock practices with MP systems and AFS, demonstrated through improvements in farm income, productivity and environment. This evidence can be extrapolated to land use in the Atlantic Forest biome. However, we emphasize the need to consider regional characteristics, socioeconomic conditions and the perspectives of producers in the development of public policies and programs to encourage sustainable agriculture. Keywords: Sustainable Development. Agroforestry System. Crop-Livestock-Forestry Integration. Rural Producer.