Pasture Recovery Period Affects Humic Substances and Oxidations of Organic Matter in Eastern Amazon

• Published in: Agronomy (Basel) Vol. 14; no. 9; p. 1937
• Main Authors: de Moraes Rego, Carlos Augusto Rocha, López de Herrera, Juan, Oliveira, Paulo Sérgio Rabello de, Muniz, Luciano Cavalcante, Rosset, Jean Sérgio, Mattei, Eloisa, Silveira, Lucas da, Sampaio, Marinez Carpiski, Pereira, Marcos Gervasio, Silva, Karolline Rosa Cutrim, de Oliveira, Ismênia Ribeiro
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.09.2024
• Subjects: Carbon; Carbon content; chemical fractionation; Deforestation; Environmental restoration; Forest management; Forests; Fractionation; Humic acid; Humic acids; Humic substances; Impact analysis; Land management; Land use; Organic matter; Organic soils; Oxidation; Pasture; pasture recovery; Principal components analysis; Recovery; Soil analysis; soil carbon; Soil chemistry; Soil degradation; Soil fertility; Soil improvement; soil management; Soil quality; Sulfuric acid; Brazil
• ISSN: 2073-4395; 2073-4395
• DOI: 10.3390/agronomy14091937

Land management practices that overlook soil limitations and potential have led to varying degrees of degradation. This study evaluates the carbon content in chemical and oxidisable soil fractions across different pasture recovery periods, comparing them to secondary forests. The management practices assessed include the following: secondary forest (SF), perennial pasture (PP), perennial pasture recovered five years ago (P5), and perennial pasture recovered eight years ago (P8), all on Plinthosols. We analysed carbon levels in oxidisable fractions and humic substances at depths of 0–0.10 m, 0.10–0.20 m, 0.20–0.30 m, and 0.30–0.40 m. The SF and P8 areas showed the highest organic matter content within the humic fractions, compared to the PP and P5 areas. Additionally, the P8 area demonstrated an increase in the labile and moderately recalcitrant fractions of organic matter, standing out among the different fractions evaluated. The multivariate principal component analysis indicated that P8 has the greatest impact on soil quality, followed by FS, P5, and PP. The pasture recovery over the past eight years has significantly improved soil carbon accumulation, highlighting the benefits of land restoration.