Biomass and carbon stock in Anadenanthera peregrina (L.) Speg stands under different planting spacings
Name: PAULO HENRIQUE DE SOUZA
Publication date: 25/01/2018
Advisor:
Name |
Role |
|---|---|
| MARCOS VINICIUS WINCKLER CALDEIRA | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| ADRIANO RIBEIRO DE MENDONÇA | Internal Examiner * |
| MARCOS VINICIUS WINCKLER CALDEIRA | Advisor * |
| VALÉRIA HOLLUNDER KLIPPEL | External Examiner * |
Summary: Issues related to climate change and rising temperatures of the Earth's atmosphere have been increasingly discussed all over the planet. In this scenario, the potential of forests to stock carbon in their biomass have been gaining prominence. The objective of this work was to verify the effect of planting spacing on biomass (BIO) and carbon stock (EC) in Anadenanthera peregrina (L.) Speg stands established in pasture area. The research was developed in the experimental area of Ifes Campus de Alegre, in Rive, Alegre, ES, Brazil. The stands were planted in June of 2011 with different spacings (3 x 2, 3 x 3, 4 x 3, 4 x 4 and 5 x 5 m), distributed in three blocks. The forest inventory was carried out to obtain the diameter at 1.30 m from the ground (DAP) and the total height of the trees (Ht) and in the sequence was sampled the BIO above the ground with the selection and felling of 45 trees. From this total, 15 trees had their root system sampled. The necromass of branches on the forest floor was sampled in 15 plots (30 x 50 m) in the area and also the soil at depths 0-5, 5-10 and 10-20 cm in all plots, obtaining the carbon content (TC) and isotopic carbon. From the individual values, regression models were fitted to estimate the population BIO for each tree compartment. The EC was calculated by multiplying BIO by the respective TC of the sample. For soil, the EC was estimated using soil and TC density in the sample. The EC obtained by BIO equations multiplied by the TC determined in the sample was more accurate in relation to the other methods tested. The mean of BIO and total EC above the ground were, respectively, 16.42 and 7.21 Mg ha-1. The relative participation of the fractions in this total was: branches (44.99%), stem (40.77%), leaves (13.99%) and bark (4.90%). For roots and necromass, the mean of BIO was, respectively, 6.68 and 1.71 Mg ha-1 and, for EC, the means were, respectively, 0.76 and 2.95 Mg ha-1. The carbon mean contents varied from 43.97% in the leaves to 44.31% in the bark, with a general arithmetic mean of 44.20%. Converting the total value of EC (EC soil + EC BIO + EC necromass) into equivalent carbon dioxide (CO2eq.) is estimated that 1161.12 Mg of CO2 were sequestered from the atmosphere. There was no effect of planting spacing on soil EC and on necromass. After 68 months of implementation of the forest stand, total soil EC was reduced by 22.72%. However, at this age, 20.99% of the soil carbon was originated from A. peregrina trees, replacing the carbon originated from the pasture. There was a tendency of higher amount of BIO and carbon in the trees in the smaller spacings, with reduction of the values in the larger spacings. The soil was the compartment that had the highest percentage of the carbon stocked (70%), followed by aerial biomass (21%), roots (6%) and necromass (3%).
Key words: land use change, organic carbon, basic density, carbon sequestration, climate change.
