Identification of savanna subtypes in the eastern Amazon (Pará and Amapá, Brazil) with a dichotomous key for individualization

Abstract

The identification and characterization of Amazonian savanna subtypes is a little explored subject. The objectives of this study were: (1) to elaborate a dichotomous key for the separation of the savanna subtypes that occur in the eastern Amazon (Pará and Amapá, Brazil), characterized on the basis of phytophysiognomic aspects; (2) to quantify (in km2) the areas of each savanna subtype, as well as their geographical spatialization; and (3) to quantify (km2) the areas of each savanna subtype within Conservation Units (UCs). Botanical inventories from different regions of occurrence of this plant typology in Pará and Amapá were compiled in a database. The dichotomous key allows one to differentiate four types of savanna (forested, wooded, park, and grassy-woodland). The area covered by savanna vegetation in the state of Pará total 60.25 thousand km2 (4.83% of the total area) and in Amapá total 8.58 thousand km2 (5.98% of the total), totaling 68.83 thousand km2, which represents 4.95% of the total area of these two eastern Amazonian states.