ire promotes functional plant diversity and modifies soil carbon dynamics in tropical savann

Autor(es)

Teixeira, Juliana ^{[1, 2, 3]} ; Souza, Lara ^{[1, 2]} ; Le Stradic, Soizig ^[4] ; Fidelis, Alessandra ^[3]

Afiliação do(s) autor(es)

^[1] Univ Oklahoma, Oklahoma Biol Survey, 111 E Chesapeake St, Norman, OK 73019 - USA

^[2] Univ Oklahoma, Dept Microbiol & Plant Biol, 111 E Chesapeake St, Norman, OK 73019 - USA

^[3] Sao Paulo State Univ Unesp, Biosci Inst, Dept Biodivers, Lab Vegetat Ecol, Av 24 A 1515, BR-13506900 Rio Claro, SP - Brazil

^[4] Tech Univ Munich, Dept Life Sci Syst, Chair Restorat Ecol, Emil Ramann Str 6, D-85354 Freising Weihenstephan - Germany

• Tipo de documento: Artigo Científico
• Fonte: Science of The Total Environment; v. 812, MAR 15 2022.
• Citações Web of Science: 0

Resumo

Fire is an evolutionary environmental filter in tropical savanna ecosystems altering functional diversity and associated C pools in the biosphere and fluxes between the atmosphere and biosphere. Therefore, alterations in fire regimes (e.g. fire exclusion) will strongly influence ecosystem processes and associated dynamics. In those ecosystems C dynamics and functions are underestimated by the fire-induced offset between C output and input. To determine how fire shapes ecosystem C pools and fluxes in an open savanna across recently burned and fire excluded areas, we measured the following metrics: (I) plant diversity including taxonomic (i.e. richness, evenness) and plant functional diversity (i.e. functional diversity, functional richness, functional dispersion and community weighted means); (II) structure (i.e. aboveand below-ground biomass, litter accumulation); and (III) functions related to C balance (i.e. net ecosystem carbon dioxide (CO2) exchange (NEE), ecosystem transpiration (ET), soil respiration (soil CO2 efflux), ecosystem water use efficiency (eWUE) and total soil organic C (SOC). We found that fire promoted aboveground live and belowground biomass, including belowground organs, coarse and fine root biomass and contributed to higher biomass allocation belowground. Fire also increased both functional diversity and dispersion. NEE and total SOC were higher in burned plots compared to fire-excluded plots whereas soil respiration recorded lower values in burned areas. Both ET and eWUE were not affected by fire. Fire strongly favored functional diversity, fine root and belowground organ biomass in piecewise SEM models but the role of both functional diversity and ecosystem structure to mediate the effect of fire on ecosystem functions remain unclear. Fire regime will impact C balance, and fire exclusion may lead to lower C input in open savanna ecosystems. (AU)

• Processo FAPESP: 15/06743-0 - Como a época do fogo afeta a vegetação do cerrado?
• Beneficiário: Alessandra Tomaselli Fidelis
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores