Effects of multiple climate change factors on exoenzyme activities and CO2 efflux in a tropical grassland

Author(s)

de Oliveira, Tassio Brito ^[1] ; de Lucas, Rosymar Coutinho ^{[1, 2]} ; de Almeida Scarcella, Ana Silvia ^[2] ; Contato, Alex Graca ^[2] ; Pasin, Thiago Machado ^[2] ; Martinez, Carlos Alberto ^[1] ; Teixeira de Moraes Polizeli, Maria de Lourdes ^{[1, 2]}

Affiliation

^[1] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Biol, Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Biochem & Immunol, Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: SOIL BIOLOGY & BIOCHEMISTRY; v. 148, SEP 2020.
• Web of Science Citations: 0

Abstract

Climate change is expected to affect rainfall dynamics and the global average temperature. Here, we evaluated the effects of those changes, the intense water deficit and warming (+2 degrees C), on a tropical grassland soil. We tested the correlation between soil extracellular enzyme activities (EEA) and soil respiration (CO2 efflux) and temperature and soil water content (SWC). A climate change simulation was performed in a field experiment using a temperature free-air-controlled enhancement facility. SWC was the main driver of changes in EEA. The most affected enzymes were beta-glucosidase, xylanase and phosphatase. As SWC declined, the potential activity of beta-glucosidase and xylanase decreased, while the activity of phosphatase and CO2 efflux increased (P < 0.01). Thus, intense drought periods are likely to have a greater influence on the rates of decomposition and mineralization in the evaluated soil than is the 2 degrees C increase in mean temperature. (AU)

• FAPESP's process: 17/09000-4 - Effects of temperature and water stress, in climate change scenario, on the fungal community in tropical soil and selection of nitrous oxide producing strains
• Grantee: Tássio Brito de Oliveira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 08/58075-8 - Miniface climate-change impact experiment to analyze the effects of elevated CO2 and warming on photosynthesis, gene expression, biochemistry, growth, nutrient dynamics and yield of two contrasting tropical forage species
• Grantee: Carlos Alberto Martinez y Huaman
• Support Opportunities: Research Program on Global Climate Change - Thematic Grants