Simulação da dinâmica espacial do desmatamento na área dos municípios sob influência direta da ponte do Rio Negro, Amazonas

Abstract

Brazil’s “Arc of Deforestation” has its configuration tied to ease of access to large consumer markets in the Southeast and South regions of the country. In the absence of such access, Western Amazonia, and more specifically Amazonas State, still retains large areas of Amazon forest. However, the construction of the Negro River Bridge, between Manaus and Iranduba, could open new frontiers for deforestation. This bridge connects Manaus (the largest economic center in the Brazilian Amazon) to a region with large areas of standing forest. The present study sought to assess the direct influence of this infrastructure on changes in the spatial dynamics of deforestation on the right bank of the Negro River in the municipalities of Iranduba, Manacapuru and Novo Airão. Using the AGROECO model, land-cover change was simulated from 2014 to 2025 in a No Bridge Scenario (NB) and a Negro River Bridge Scenario (NRB). Historical deforestation rates were used as the premise for each scenario. For the PRN scenario, the historical rates referred to the period from the beginning of bridge construction (2008) until 2012, and for the SP scenario the 2003 to 2007 period was used. The result obtained for the amount of deforestation between 2013 and 2025 in the total three-municipality study area was 19,650 ha in the NRB scenario and 15.393ha in the NB scenario, that is, 27.7% more deforestation occurred over this period in the scenario with the bridge. Considering only the municipalities of Iranduba and Manacapuru, where deforestation increased in the Negro River Bridge scenario, the increase was 33.4% in this scenario. The spatial distribution in both scenarios was very similar, but a difference was found along the AM-352 Highway that, cuts through the western side of the municipality of Iranduba. The simulated scenarios demonstrated the potential for changes in the distribution of deforestation on the right bank of the Negro River as a result of the bridge. The metropolis of Manaus is in a phase of rapid horizontal expansion, thus greatly increasing interest in the land on the other side of the Negro River. Areas that were previously difficult to access may now be exposed to more pressure and deforestation.