Analysis of changes in land use and land cover in permanent preservation areas in Jari (RS)

Abstract

The expansion of soybean cultivation into less favorable or restricted areas, including PPA, has been driven by the demand for new agricultural lands. This study analyzed the dynamics of LULC in the PPA of Jari (RS) between 1985 and 2023, using data from MapBiomas. Classified data from the Landsat series, Collection 9, extracted from the GEE platform, were evaluated for the years 1985, 1995, 2005, 2015, and 2023. The results indicate that between 1985 and 2023, grassland formations in spring PPA decreased from 71% to 30% (a loss of 910,000 m²), while soybean cultivation expanded from 4% to 46% (an increase of 960,000 m², or 1,200% growth). In PPA along watercourses, grassland and forest formations predominated in 1985, with 47% and 45%, respectively. However, forest cover lost 200,000 m², and grassland was reduced to 23% of the total area. Soybean, which accounted for only 1% of these PPA in 1985, expanded to 22% in 2023 (an increase of 10,910,000 m², with a growth rate of 2,948.65%). The conversion of natural vegetation to soybeans was favored by Oxisols and gently undulating relief in the northern part of the municipality, while in the south, Entisols and steeper slopes contributed to the preservation of natural areas. The results highlight the urgent need for public policies for PPA protection, recovery of degraded areas and strict enforcement, ensuring environmental sustainability and water security in the municipality.