Forest dynamics and land-use transitions in the Brazilian Atlantic Forest: the case of sugarcane expansion

Abstract

In this research, we investigate how forest cover and land use have evolved in an area of rapid expansion of sugarcane, located within the Brazilian Atlantic Forest (AF) biome. A 23-year satellite image time series and data from the Brazilian agricultural censuses were used to assess forest cover and land-use changes at regional scale. A methodology was developed to map forest remnants and regeneration patches, for which size and isolation were analyzed. Censuses statistics showed major changes on pastureland, cropland, cattle stocking rate, milk, and family agricultural production. Forest cover represented approximately 4.4 % of the study area, including forest regeneration, which accounted for 2.4 % of total forest cover. Few large forest fragments accounted for most of the total forest cover, with smaller, more numerous fragments ensuring most of patch isolation, with an average distance between fragments of 987 m. Spatial distribution analysis revealed that a third of all forest fragments were located within 50 m from riverbeds, suggesting that enforcing mandatory preservation of riparian vegetation may improve patch connectivity. Censuses statistics showed that sugarcane area increased by more than 200 %, while pasture area decreased by a fifth, but yet accounted for 61 % of farmland, where extensive cattle breeding was predominant. As large-scale sugarcane expanded, rural activities typical of family agriculture such as cattle breeding and milk production declined. Simultaneously, cattle stocking rate increased promoting land-use intensification in pastureland. Finally, the developed methodology may be useful to detect forest regeneration, using remotely sensed data, in other AF areas.