Ecological effects of changes on Brazilian native vegetation protection law in an urban area

Abstract

This study compared the ecological effects on forest conservation before and after changes in Brazilian forest protection, taking a case study of a water source area in Diadema, the municipality with the highest demographic density in São Paulo State. We also evaluated compliance with the laws (Forest Code—FC and Native Vegetation Protection Law—NVPL), considering the reality of land use and land cover (LULC) in the year before the new law NVPL. We created LULC maps of legal scenarios for both laws analyzed based on landscape metrics of optimal resource availability (ORA), distance from the nearest neighbor (ENN), and anthropogenic edge frequency and length (ESD and ED). Our findings revealed that changes to some technical criteria in the NVPL reduced the quantity (220–105 ha) and quality (ORAFC = 0.02 and ORANVPL = 0.005) of Diadema protected forests and altered their neighborhood relationships, stronger influenced by human-modified fields as agents of fragmentation and pressure for further disturbances. The results indicate that the new law does not substantially increase compliance (30–35%), but if it has full compliance, landscape connectivity could be improved (ENNFC = 8.6 and ENNNVPL = 11.2). Our technique to create a LULC map of legal expectation, combined with the application of selected landscape metrics, proves valid for understanding the changes in Brazilian expectative protection regarding forest conservation.