Enzymatic activity and CO2 emission by soil microbiota as a function of variation in ambient temperature of an Oxisol under degraded pasture and under crop-livestock-forest integration.

• Grant number: 24/03712-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date until: August 01, 2024
• End date until: July 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Luís Reynaldo Ferracciú Alleoni
• Grantee: Bruno Stella
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated research grant: 21/10573-4 - Center for Carbon Research in Tropical Agriculture (CCARBON), AP.CEPID

Abstract

The changes in land use resulting from human activities, along with the growth of industrial production, have caused significant impacts on ecosystems. One of the main effects of these changes is the increase in the concentration of carbon dioxide (CO2) in the atmosphere, which is linked to emissions resulting from the burning of fossil fuels, deforestation with fire, and other practices that release carbon stored in the soil and vegetation. Thus, there has been growing interest in the use of agricultural land for carbon sequestration, which enables opportunities to integrate animal and agricultural productions, playing a significant role in the pursuit of climate mitigation goals. The adoption of integrated systems, such as the integration ofcrop-livestock-forest (ICLF), is a practice used to address these environmental problems and meet the demands of the food and carbon credit markets. This project aims to evaluate the impact of ambient temperature variation on chemical and biological attributes of a dystrophic Red-Yellow Latosol of medium texture under degraded pasture (DP) and under ICLF, with the results compared to those of the soil under native forest (NF). The area under DP has been managed for 30 years without the use of inputs, which represents a large part of the pastures in Brazil. In turn, the ILPF system has been conducted for 12 years with the use of limestone and fertilizers, while the third system is a fragment of NF. Soil samples will be incubated in a bio-oxygen demand (BOD) chamber at temperatures of 20º and 30ºC to simulate the effect of global warming by 10ºC. The incubation time will be monitored in accordance with the results of soil basal respiration, and the observed stabilization will determine the end of the experiment. At the end of the incubation, soil chemical characterization will be performed, as well as enzymatic analysis (²-glucosidase,acid phosphatase, and arylsulfatase), organic matter fractionation (total organic carbon and total nitrogen), characterization of functional groups of organic matter by Fourier-transform infrared spectroscopy and dissolved organic carbon. The expectation is that the results obtained can help promote the implementationof sustainable agriculture. The project is linked to the Carbon Studies Center (CCARBON, process nº2021/10573-4) of USP and FAPESP, which seeks to propose innovative and sustainable solutions forBrazilian agriculture.