Padrões, Trajetórias e Simulação do Desmatamento em Lábrea, Sul do Amazonas

Abstract

In recent years the loss of forest in the Amazon region has taken on alarming proportions, with the largest increase in 13 years being observed in 2021. Understanding the process and dynamics of deforestation in different land-tenure categories allows the projection of future scenarios to address possible changes in relation to land-use and land-cover classes. In this study, we analyzed the patterns and trajectories of deforestation and simulated land-use change up to 2080 by delimiting a 10-km buffer around the municipality of Lábrea, located in the southern portion of the state of Amazonas. Using data from PRODES (Project for Monitoring Deforestation in the Amazon by Satellite) from 2008 to 2021, the clear-cut deforestation polygons were classified based on landscape metrics and occupation typologies defined for the region (i.e., diffuse, linear, herringbone, geometric, multidirectional, and consolidated). This process was carried out using cellular grids with 10 × 10 km resolution. The different trajectories of deforestation were evaluated from the temporal analysis of these patterns. Finally, the patterns and trajectories were associated with different land-tenure categories and the region's occupation process. Self-declared claims in the Rural Environmental Register (CAR) are referred to, albeit inaccurately, as "properties." Using a dynamic spatial model, future scenarios were simulated for the Lábrea region up to the year 2080. For this, the study area was divided into the following regions: areas with properties smaller than 100 ha, areas with properties larger than 100 ha, rural settlements, protected areas, and undesignated lands. Based on the deforestation rates calculated for each region for the period from 2010 to 2019, two future scenarios were constructed: (i) "Baseline Scenario" (LB), which used the historical rates (2010-2019) for the entire simulation period and (ii) "Expansion Scenario" (CE) which simulated an increase in deforestation rates with the construction of the planned highways (i.e., BR-230, BR-317 and AM-165), which is assumed to occur in the year 2045. The increase in deforestation rates occurred for the regions of properties larger than 100 ha, protected areas, and undesignated lands. For this rate increase, the most recent deforestation rates (i.e., from 2015 to 2021) were used as the reference. The results for deforestation patterns and trajectories indicated that most of the territory of Lábrea is composed of the diffuse pattern, which is mainly concentrated in protected areas. The patterns associated with the most advanced levels of occupation (i.e., multidirectional, and consolidated) were those that most contributed to deforestation. The trajectory observed in Lábrea consists of consolidation in the southern portion of the municipality and expansion into the central part of the municipality from the Boi and Jequitibá access roads, which are mainly occupied by large properties. The modeling of deforestation showed that in the CE scenario there would be a larger area deforested after the construction of the planned roads, impacting mainly the protected areas and favoring deforestation on properties overlapping the protected areas. Both scenarios warn of an expansion of deforestation on properties larger than 100 ha and on undesignated lands. The CE scenario also warns that road construction will allow access to forests within protected areas, which increases the chances of these forests being deforested and illegally occupied.