Deforestation analysis in protected areas and scenario simulation for structural corridors in the agricultural frontier of Western Bahia,Brazil

The aim in this paper was to evaluate the spatial distribution of protected areas defined by law and their importance as structural corridors. The study area was 7,559,783.69 ha located in Western Bahia (Northeast Brazil), restricted to the limits of the Urucuia Group (Upper Cretaceous), where there is strong agribusiness growth. Currently, a major dilemma in Brazilian public policy arises from the conflicting interests of environmental conservation and increased food production. Brazilian environmental protection policies include the implantation of Protected Areas (Full Protection Units and Sustainable Use Units) and the adoption of the National Forest Act (Permanent Preservation Areas and Legal Reserves). In this context, we delimited illegal land-use in Permanent Preservation Areas (PPAs) adopting the intersection between land-use/land-cover data from PRISM/ALOS image classification for the years 2007–2010 and PPA vectors. We performed the temporal analysis in PAs considering land-use/land-cover data from Landsat TM image classification for the years 1988, 1992, 1996, 2000, 2004, 2008 and 2011. Finally, we performed a Morphological Spatial Pattern Analysis (MSPA) to evaluate whether PPAs alone are sufficient as structural corridors. Hypothetical scenarios were simulated to increase the potential of PPAs as structural corridors. The calculation of MSPA attributes was conducted considering 3 edge widths: 15 m (1 pixel), 510 m (34 pixels), and 1005 m (67 pixels). Four scenarios were simulated, considering a gradual increase in preserved areas. The results show that illegal land use is contained within PPA and protected areas. The scenario simulations present alternatives to increase the connectivity of the fragments and ensure the maintenance of ecological and hydrological services. Rapid agricultural expansion without proper landscape planning can compromise the sustainability of ecosystem services and the recharge zone of the Urucuia aquifer.