Carbon estimates in a neglected non-forest ecosystem: Aboveground biomass in a tropical cloud savanna in Southeastern Brazil

Abstract

Plant communities store carbon in their biomass, contributing to the reduction of greenhouse gases in the atmosphere. Many studies about aboveground biomass (AGB) have been conducted in the Brazilian Atlantic Forest, but non-forest ecosystems (NFE) remain neglected. This is the case of cloud savannas that occur at high altitudes (>800 m) in the Mantiqueira Mountain Range, Southeastern Brazil. To evaluate wood structure and live AGB variation in this phytophysiognomy, we carried out an inventory of woody and dead stems in the 1-ha permanent sample in the Ibitipoca State Park (Minas Gerais, Southeastern Brazil). We measured (diameter and height) and identified all woods with DB ≥ 3 cm (diameter at base level = 0.30 m above soil) in a sample of 10 random permanent plots (50 × 20 m). We estimate the AGB by the wood community based on trunk samples (wood density) and global allometric equations. We sampled a total of 1480 woods, of which 1055 (71.3%) were living and 425 (29.7%) were standing dead woods. The species Eremanthus erythropappus (Asteraceae) was dominant, with 56% of the individuals and 73% of the basal area. The total aboveground biomass (AGB) estimated for the community was 10.5 ton.ha−1, where 8.8 ton.ha−1 (83.9%) was for the live and 1.7 ton.ha−1 (17,1%) for the standing dead woods. The AGB values in our study were lower than those registered in surrounding forests and other NFEs (savanna) types in Brazil, probably related to the sandy poor soils. To the best of our knowledge, this study is the first one that quantifies AGB in a cloud savanna in Brazil. Knowledge of aboveground carbon storage in this NFE could be used to encourage REDD+ and CDM projects since it is a widespread and threatened vegetation type over very erodible soils along the Mantiqueira Mountains Range.