Cutting of dry forests in a semiarid region of northeastern Brazil.

Dry forests are one of the most threatened ecosystems in the world, and they are poorly protected. The semiarid region of northeastern Brazil is the largest area in the New World with a predominance of dry forests, although it has been estimated that half of Brazil’s original semiarid vegetation has already been removed. This study assesses the extent of changes in areas covered by native dry forests (Caatinga) over a period of 46 years (1973–2019) in the southern portion of the semiarid region in Brazil’s State of Bahia. The study area encompasses 18 municipalities (counties) with a total area 2,344,733 ha. To map changes in vegetation cover, Landsat satellite images were used for the years 1973, 1987, 2001, and 2019. The area with native vegetation was reduced by 614,100 ha between 1973 and 2019. The area with vegetation declined in all municipalities; however, the intensity of changes in land use varied among the analyzed periods, with 77.1% of the reduction in vegetation cover occurring between 1973 and 1987. In the 1990s, the intensity of cutting of native vegetation decreased, mainly due to a decrease in the area planted to cotton, while natural regeneration increased. Cutting native vegetation resumed in the 2000s while regeneration declined. In 2019, the remaining vegetation was almost completely restricted to hills or mountains and was in fragments composed of a mosaic of vegetation in different stages of regeneration. Areas that still have native vegetation must be preserved, including those that are regenerating from past clearing. [ABSTRACT FROM AUTHOR]