%0 Journal Article
%4 sid.inpe.br/mtc-m21d/2023/03.13.16.15
%2 sid.inpe.br/mtc-m21d/2023/03.13.16.15.55
%@doi 10.3390/ijerph20043485
%@issn 1661-7827
%@issn 1660-4601
%T Soil organic matter molecular composition shifts driven by forest regrowth or pasture after slash-and-burn of Amazon forest
%D 2023
%8 Feb.
%9 journal article
%A Leal, Otávio dos Anjos,
%A Jiménez-Morillo, Nicasio T.,
%A González-Pérez, José A.,
%A Knicker, Heike,
%A Costa, Falberni de Souza,
%A Jiménez-Morillo, Pedro N.,
%A Carvalho Júnior, João Andrade de,
%A Santos, José Carlos dos,
%A Dick, Deborah Pinheiro,
%@affiliation Institute of Bio- and Geosciences—Agrosphere (IBG-3)
%@affiliation Universidade de Évora
%@affiliation Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS-CSIC)
%@affiliation Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS-CSIC)
%@affiliation Embrapa Acre
%@affiliation Universidad Pablo de Olavide
%@affiliation Universidade Estadual Paulista (UNESP)
%@affiliation Instituto Nacional de Pesquisas Espaciais (INPE)
%@affiliation Universidade Federal do Rio Grande do Sul (UFRGS)
%@electronicmailaddress o.dos.anjos.leal@fz-juelich.de
%@electronicmailaddress
%@electronicmailaddress
%@electronicmailaddress
%@electronicmailaddress
%@electronicmailaddress
%@electronicmailaddress
%@electronicmailaddress jose.santos@inpe.br
%B International Journal of Environmental Research and Public Health
%V 20
%N 4
%P e3485
%K Acrisol, analytical pyrolysis, Brachiaria, Brazilian Amazon, experimental burning, n-alkanes, van Krevelen 3D diagrams.
%X Slash-and-burn of Amazon Forest (AF) for pasture establishment has increased the occurrence of AF wildfires. Recent studies emphasize soil organic matter (SOM) molecular composition as a principal driver of post-fire forest regrowth and restoration of AF anti-wildfire ambience. Nevertheless, SOM chemical shifts caused by AF fires and post-fire vegetation are rarely investigated at a molecular level. We employed pyrolysisgas chromatographymass spectrometry to reveal molecular changes in SOM (010, 4050 cm depth) of a slash-burn-and-20-month-regrowth AF (BAF) and a 23-year Brachiaria pasture post-AF fire (BRA) site compared to native AF (NAF). In BAF (010 cm), increased abundance of unspecific aromatic compounds (UACs), polycyclic aromatic hydrocarbons (PAHs) and lipids (Lip) coupled with a depletion of polysaccharides (Pol) revealed strong lingering effects of fire on SOM. This occurs despite fresh litter deposition on soil, suggesting SOM minimal recovery and toxicity to microorganisms. Accumulation of recalcitrant compounds and slow decomposition of fresh forest material may explain the higher carbon content in BAF (05 cm). In BRA, SOM was dominated by Brachiaria contributions. At 4050 cm, alkyl and hydroaromatic compounds accumulated in BRA, whereas UACs accumulated in BAF. UACs and PAH compounds were abundant in NAF, possibly air-transported from BAF.
%@language en
%3 ijerph-20-03485-v2.pdf