Efeitos de diferentes intensidades de anelamento sobre a estrutura de uma floresta de terra firme na Amazônia Central

Abstract

The objective of this study was to analyze the effect of four reduced intensities of basal area by girdling, in floristic diversity, horizontal structure, basal area, volume, biomass and carbon of a mainland forest in central Amazonia, after a period of approximately 28 years, since the intervention. The experiment is located at Station (ZF-2) of the INPA, Manaus-AM. The statistical design was randomized blocks with three replications and 5 treatments, with dimensions of one hectare each: T0: control without any intervention; T1: girdling the trees with DBH ≥ 60 cm + 4 trees with DBH ≥ 50 cm not listed species, to reduce 25% of the basal area; T2: girdling the trees with DBH ≥ 50 cm + 12 trees with DBH ≥ 40 cm not listed species, 50% of the basal area; T3: girdling the trees with DBH ≥ 40 cm + 21 trees with DBH ≥ 30 cm not listed species, 75% reduction of the basal area; T4: girdling of all tree species not listed with DBH ≥ 25 cm, 100% reduction of the basal area. For area girdling the forecast variables in treatments T0, T1, T2, T3 and T4 were reported the following values for the settlement with DBH ≥ 10 cm, respectively: Number of trees (614 ± 59; 541 ± 57; -1 551 ± 40 , 541 ± 41; 626 ± 95 and árv.ha ); Basal area (31.45 ± 1.99; 29.55 ± 2.39; -1 28.35 ± 1.57; 27.15 ± 5.14; 25.73 ± 3.43 m².ha ); Volume (468.78 ± 29.70; 440.39 ± -1 35.59; 422.56 ± 23:42; 404.66 ± 76.58; 383.62 ± 51.06 m³.ha ); Total biomass (716.12 ± 48.58; 674.01 ± 56.53; 662.62 ± 57.82; 618.17 ± 117.63;. 595.92 ± 80.46 -1 Mg ha ) and total carbon (202.83 ± 13.76; 190.91 ± 1.16; 187.68 ± 16:38; 175.09 ± -1 33.32; 168.79 ± 22.79 Mg ha ). The results indicate that the remaining forest is responding positively to the application of different intensities of girdling. The T4 was considered the treatment that achieved the best results. Despite having lower values for the variables: basal area, volume, biomass and carbon, this was the treatment that showed the highest recovery rates for these variables