Biomassa aérea e fatores de expansão de uma floresta estacional decidual em Niquelândia, Goiás

Abstract

We estimated biomass for different aboveground compartments of a deciduous forest in Niquelândia, Goiás, Brazil, and determined expansion factors for necromass, litter, herbaceous layer, tree poles, and undergrowth. The tree sample comprised 20 (10 x 10 m) plots of trees with diameter at breast height (dbh) ≥ 5 cm, distributed in four transects (five plots per transect). Plots placed 50 m apart along the transects. For each plot, we sampled the following compartments in five (1 x 1 m) subplots: tree poles (dbh < 5 cm and height (h) ≥ 1.5 m), undergrowth (trees, shrubs and herbs with h < 1.5 m), necromass, and litter. The herbaceous layer sample consisted of one (0.4 x 0.6 m) subplot per plot. Tree biomass was estimated with the equation: ln (AGB) = - 10.4398 + 2.1183 * ln(dbh) + 0.8339 * ln(h), where AGB = tree aboveground biomass, dbh = diameter at breast height (cm), h = height (Mg). Biomass fresh weight of the other compartments was determined on site, and for each subplot, a 500 g sample was taken to the laboratory to determine its dry weight. Tree aboveground biomass was 100.67 Mg ha-1 (± 30.97 Mg ha-1), necromass was 1.0472 Mg ha-1 (± 0.3403 Mg ha-1), litter biomass was 2.7498 Mg ha-1 (± 0.2932 Mg ha-1), herbaceous layer biomass was 0.2398 Mg ha-1 (± 0.1789 Mg ha-1), tree-pole biomass was 0.8184 Mg ha-1 (± 0.3257 Mg ha-1), undergrowth biomass was 0.2583 Mg ha-1 (± 0.0941 Mg ha-1). Expansion factors for necromass, litter, herbaceous-layer, tree-pole, and undergrowth were 0.0104, 0.0273, 0.00248, 0.0081 e 0.0026, respectively.