Soil Physical Quality in Sugarcane Field Under Cover Crop and Different Soil Tillage Systems

C V V Farhate,J L N Carvalho,M C C Campos,W S Guimarães Jr,Z M Souza,A C M Sousa

doi:10.5539/jas.v10n11p489

Abstract

Currently, the management practices employed in Brazilian sugarcane plantations have contribute to soil physical degradation and, few studies considering the effect of cover crop associated with conservationist soil tillage systems to control or even reverse this process. Therefore, with the aim to assess the impact of cover crop and tillage systems on the least limiting water range (LLWR) and the S index in two soils of different textures used for sugarcane production, a fieldwork was carried out in two sugarcane plantations in the state of S&atilde;o Paulo, Brazil. The experimental design is a split-plot with four repetitions. The main factor consisted of soil cover vegetation: cover crop and fallow, and the second factor, the tillage system: minimum tillage and conventional tillage. The data of this study demonstrated that clayey and medium-textured soil are sensitive to the management systems used. The use of cover crop promoted an increase of LLWR (average incremental rate of 105% for clayey and 100% for medium-textured soil) and S index (average incremental rate of 16% for clayey and 10% for medium-textured soil). The maintenance of soil under fallow represented restrictive conditions for the growth/development of the plants due to the degradation of the soil structure. In addition, conservation management systems, such as minimum tillage, resulted in better soil physical quality when associated with cover crop. Finally, the clayey and medium-textured soil, show good S index during the first cycle of sugarcane cultivation.

Highlights

Sugarcane cultivation was introduced in Brazil since the colonial period and presents a highlight position in the national economy due to the planted area, nine million hectares (Conab, 2018), which generate directly and indirectly millions of jobs (Neves & Trombina, 2014) and energy potential (Cortez, 2010).sugarcane monoculture, intensive soil tillage, and machinery in-field traffic lead to accelerated soil physical degradation
The least limiting water range (LLWR) comprises three factors—soil aeration, soil water retention and soil penetration resistance—that affect plant growth in a single variable. It is used as an indicator of soil structural quality for crop production and as a parameter to characterize the impact of soil management practices on sustainable productivity of soils (Silva et al, 1994)
The objective of the study was to assess the impact of cover crop and tillage systems on the LLWR and the S index in two soils of different textures used for sugarcane production

Summary

Introduction

Sugarcane cultivation was introduced in Brazil since the colonial period (between the XVI and XIX centuries) and presents a highlight position in the national economy due to the planted area, nine million hectares (Conab, 2018), which generate directly and indirectly millions of jobs (Neves & Trombina, 2014) and energy potential (Cortez, 2010).sugarcane monoculture, intensive soil tillage, and machinery in-field traffic lead to accelerated soil physical degradation. The use of conservation management systems, such as minimum tillage and no-tillage, can help maintaining soil productivity since crop residues are left on the soil surface under both systems, and tillage is minimal and/or restricted to planting rows. The LLWR comprises three factors—soil aeration, soil water retention and soil penetration resistance—that affect plant growth in a single variable. It is used as an indicator of soil structural quality for crop production and as a parameter to characterize the impact of soil management practices on sustainable productivity of soils (Silva et al, 1994)

Objectives

Methods

Results

Conclusion