This study applied a deforestation model for the entire State of Rondônia assuming three scenarios of deforestation: business as usual, optimistic and pessimistic. Those scenarios were constructed for the time-period of 2012-2050 using the Dinamica EGO software. Rondônia deforestation dataset was provided by the Agência Ambiental do Estado de Rondônia (Rondônia State Environmental Agency) and was used as input of the deforestation modeling. Based on this study results, we estimated that 32%, 37% and 47% of Rondônia's native forest could be fully deforested by 2050 assuming the optimistic, business as usual and pessimistic scenarios, respectively. Regardless of the chosen scenario, we expect that deforestation will be spatially concentrated in Northern Rondônia in the next decades. The greatest concern, however, could be the integrity of the protected areas assuming the business as usual and/or pessimistic scenario. In addition, we expect a substantial increase of the forest fragmentation by 2050.

Facing increasingly competitive market demands, producers must act as managers of their property, knowing the strengths and bottlenecks in production systems. In this perspective, there is a methodology activity-based costing system (ABC), a cost management tool, used when there is a mix of products, to determine the unit costs of production. This work aimed to apply the activity-based costing system to activities in a successional agroforestry system, that produces nine products. The methodology was applied to the indirect costs of the system. When applying the methodology, it was found that maize and okra products presented negative contribution margins, showing that the respective production costs exceed the sale value of the product. The other products had positive contribution margins, with emphasis on yam and strawberry. The ABC system is efficient for management and administration of agroforestry enterprises.

O manejo florestal é uma boa alternativa à exploração predatória dos recursos florestais. Para aumentar a adoção do manejo florestal e evitar o desmatamento ilegal e a ocupação desordenada das florestas públicas, o Governo instituiu a política de concessão florestal. O estudo teve por objetivo descrever a trajetória da política de concessão florestal no Brasil, abordando seus avanços, bem como os aspectos positivos e negativos da modalidade de gestão de florestas públicas supracitada. O trabalho foi realizado por meio de revisão bibliográfica sobre o manejo florestal, com destaque para as concessões florestais no Brasil. Atualmente, o Brasil possui 6 (seis) FLONAs sob concessão, sendo 4 (quatro) delas no estado do Pará, e 2 (duas) em Rondônia. Até o momento, as concessões florestais não atenderam às expectativas iniciais. Como pontos positivos, pode-se observar a redução da vulnerabilidade das florestas sob concessão e a geração de empregos diretos, beneficiando a população local. A destinação de áreas para a concessão ficou abaixo do planejado pelo governo. No entanto, apesar da lenta implantação, espera-se que haja uma rápida expansão devido às lições adquiridas com os primeiros contratos. Assim, acredita-se que o processo de concessão florestal brasileiro está amadurecendo de forma lenta, mas gradual. As atividades de monitoramento e fiscalização são consideradas elementos frágeis das concessões florestais, sendo necessárias ações que garantam a sustentabilidade das florestas. A redução da exploração ilegal é um desafio para o governo. Assim, caso o mercado seja abarrotado de madeira advinda da exploração ilegal, o esforço realizado para implantar a política de concessão florestal poderá ter sido em vão. Por fim, as concessões florestais são recentes no Brasil, mas estão evoluindo a cada ano, tanto em quantidade de áreas destinadas quanto de produtividade de madeira. Nesse contexto, pesquisas se fazem necessárias para um maior conhecimento dos resultados apresentados pela gestão.

Background:Litter is an important component of ecosystems, and its characteristics (e.g., production, decomposition, and nutrient and carbon content) are relevant for the ecological maintenance of different ecosystems. Previous studies on decomposition patterns have focused only on short time periods. Furthermore, there is no information regarding the actual decomposition time of organic matter in the Brazilian savanna biome known as the Cerrado. Thus, analysis of the total decomposition time can provide reliable estimates for other models. This study aimed to evaluate total litter decomposition (100%) and its relationship with seasonality and floristic composition in the savanna forest (Cerradão) formation in central Brazil. Litter bags were randomly distributed over the soil, with 10 samples collected per quarter from August 2014 to May 2020. Single-and double-entry linear regression models were used to analyze the total litter decomposition. Results:The half-life (time for which 50% of the litter was decomposed) occurred at 360 days, and 100% of litter decomposition occurred at 2.070 days. The single-entry model was more satisfactory for estimating the decomposition speed. There was a positive correlation between litter decomposition and precipitation, and the floristic composition helped to explain the litter decomposition trends. Conclusion:Litter decomposition in the Cerradão is related to floristic diversity (quality of the material) and to the synergism of factors that occur mainly in the rainy season. Thus, the results of this study can contribute to conservation initiatives.

Most of the studies that analyze the behavior of tree competition approach even-aged plantations. Therefore, it is possible to notice a lack of this kind of information regarding natural forests with high biodiversity. The objective of this study was to evaluate the competition in a fragment of Semi-Deciduous Seasonal Forest, according to the ecologic group, light depending and non-depending groups for all species sampled in the fragment. The Distance Independent Competition Index and Semi-Distance Independent Competition Index were applied in this study. The basal area in larger trees index, without the radius of influence, was the most efficient to analyze how the competition affects the growth of the specimens in the studied fragment. It was stated that evaluating the competition per ecologic group is more efficient. The results confirm that the forest competition cannot be determined by considering only a fixed radius of influence that embraces the neighbors and the subject tree.