Changes in soil biodiversity induced by the expansion of sugarcane cultivation over extensive pasture areas

• Grant number: 19/16764-6
• Support type: Scholarships in Brazil - Master
• Effective date (Start): March 01, 2020
• Effective date (End): February 28, 2021
• Field of knowledge: Agronomical Sciences - Agronomy - Soil Science
• Principal Investigator: Maurício Roberto Cherubin
• Grantee: Beatriz da Silva Vanolli
• Home Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

The expansion of sugarcane cultivation over degraded pastureland has been one of the main scenarios for land use change (LUC) in the central southern Brazil. However, such conversion may result in negative impacts on soil biodiversity, and the multiple functions and services associated with these organisms. Given this, this project aims to evaluate the changes in soil biodiversity induced by the expansion of sugarcane cultivation over extensive pasture areas. Two sites will be studied in the state of São Paulo, with contrasting soil texture, which present chronosequences land use change that includes: i) native forest, ii) degraded pasture, iii) plant sugarcane over pasture area; and iv) Sugarcane ratoon. Monoliths (25 x 25 x 10 cm) and disturbed soil samples were collected at depths 0-10, 10-20, 20-30 cm for the evaluation of macro- and mesofauna of soil and microorganisms, respectively. Near each collection point, drop traps were installed to evaluate the epigeous macrofauna of the areas. The invertebrates of the macro-edaphic, epigeal and mesofauna will be quantified and identified with the aid of the stereoscopic microscope. The microorganisms (i.e., bacteria, archea and fungi) will be quantified through the qPCR technique and microbial biomass. After extraction and identification of the organisms, the total abundance of organisms, taxonomic richness and diversity index of Shannon (H ') will be determined. This research will contribute to a better understanding of the impacts of the expansion of sugarcane cultivation on soil biodiversity and also, the information generated will serve as parameters to measure and compose integrated assessments of soil quality and provision of ecosystem services. (AU)