Sugarcane cultivation effects on soil physical properties, functions, and related-ecosystem services

• Ano de defesa: 2022
• Autor(a) principal: Luz, Felipe Bonini da
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Agricultural traffic control; Bioenergy; Bionergia; Conservação do solo; Controle de tráfego ágricola; Estrutura do solo; no-tillage; Qualidade do solo; Sistema plantio direto; Soil conservation; Soil health; Soil structural quality
• Link de acesso: https://www.teses.usp.br/teses/disponiveis/11/11140/tde-03012023-114757/

Brazil is the worlds largest sugarcane producer and is committed to promoting sugarcane production in the following years. However, sugarcane expansion can degrade soil physical quality and related soil functions due to management practices such as conventional tillage and random machinery traffic. Conversely, conservation tillage practices such as reduced tillage and the adoption of traffic-free seedbed zones have been investigated as management practices that can improve soil structure and, consequently, its functional capacity. The hypotheses of this study are that i) sugarcane expansion under conventional tillage on pasture areas degrades soil structure and reduces the related soil functions and ii) the adoption of reduced tillage and traffic-free seedbed zones instead of conventional tillage improves soil structure and consequently the related soil functions. The overall objective of this study was to evaluate the effects of a typical land-use change sequence (native vegetation pasture sugarcane) on soil functions for sugarcane expansion and the adoption of different tillage practices in its cultivation. To meet this objective, this study has assessed i) the effects of a typical land-use change sequence for sugarcane expansion on soil physical quality and water dynamics in contrasting soil textures, ii) soil water availability and air flux indicators in two soils with contrasting textures under conventional and reduced tillage practices associated with random and without machinery traffic, iii) the effects of conventional and reduced tillage practices with random and without machinery traffic on soil structure, and iv) the impacts of agricultural traffic control on soil physical properties and related functions under contrasting soil textures. The findings showed that conversion from native vegetation to extensive pasture induced severe degradation in soil physical quality. On the other hand, conversion from pasture to sugarcane did not cause additional degradation on soil structure and soil water dynamics. In general, conventional tillage and reduced tillage under random traffic showed similar soil structure and soil water availability and air fluxes. However, the adoption of reduced tillage and traffic-free seedbed zones improved soil structure regardless of assessment scales (i.e., micro and macro scales) and it also preserved soil water availability and air fluxes. In addition, agricultural traffic control supported soil physical functionality and soil physical quality at the seedbed position and it did not reduce soil physical functionality related to uncontrolled traffic at the sugarcane inter-row position. Lastly, this study identified that adopting reduced tillage and traffic-free seedbed zones are two of the most important pillars for reducing soil compaction in sugarcane fields and, consequently, can contribute positively to provide natures contribution to people.