Developments in the “profil cultural” method for an improved assessment of soil structure under no-till

Abstract

CT3 ; EnjS3 ; Département EAIn France, agronomists have studied the effects of cropping systems on soil structure using a field method that is based on a visual description of the soil structure. This “profil cultural” method was designed as a field diagnostic tool to identify the effects of tillage and compaction on soil structure dynamics. It is of great benefit to agronomists seeking to improve crop management and preserve soil structure and fertility. However, the “profil cultural” method was developed and has mainly been used in conventional tillage systems with regular ploughing. As there has been an increase in the use of various forms of reduced, minimum and no-tillage systems in many parts of the world, it is necessary to re-evaluate this method’s ability to describe and interpret soil structure dynamics in no-till or reduced tillage. In these situations, changes in soil structure over time are mainly driven by compaction and by regeneration through natural agents (climatic conditions, root growth and macrofauna), therefore it is important to evaluate the effects of these natural processes on soil structure dynamics. These concerns have led to adaptations and amendments to the initial method based on field observations and experimental work in different cropping systems, soil types and climatic conditions. The description of crack types has been improved and a criterion of biological activity based on the visual examination of clods has been introduced. To test this modified method, a comparison with the initial method was undertaken and its ability to make diagnoses tested in five experiments in France, Brazil and Argentina. The adapted method allowed an improved assessment of the impact of cropping systems on soil functioning when natural processes were integrated into the description

Soil morphostructural characterization and coffee root distribution under agroforestry system with Hevea Brasiliensis

“…Soil morphostructural characterization is essential to assess SQ since changes in properties, such as aggregate size, type, and development, affect soil permeability, aeration as well as root growth and microorganism development (Boizard et al, 2017;Silva et al, 2014). Thus, the cultural profile method to identify soil structural changes resulting from agricultural practices and evaluate the effects on soil conservation and quality (Silva et al, 2014) are of great importance, as in the intercropped areas evaluated in this study.…”

Physical Properties of Soil Structures Identified by the Profil Cultural under Two Soil Management Systems

“…The cultivated layer is subject to considerable spatial variability, unlike horizons that are not usually affected by tillage (Neves et al, 2003;Fuentes-Llanillo, 2013;Gonçalves et al, 2013;Tavares Filho et al, 2014;Boizard et al, 2016). This variability often allows plants to grow in compacted soils, taking advantage of the flow of water and gas through structural discontinuities (cracks) that also allow root growth (Neves et al, 2003;Reichert et al, 2016).…”

“…Studies have shown that this method of soil profile analysis can be helpful in qualitative evaluation of soil management (Coulomb et al, 1993;Roger-Estrade et al, 2000b;Mueller et al, 2009;Mueller et al, 2013;Munkholm et al, 2013;Guimarães et al, 2013;Tavares Filho et al, 2014;Boizard et al, 2016). It enables researchers to establish links between soil structure and other factors, such as root development (Roger-Estrade et al, 2000a;Mentges et al, 2016), the availability and distribution of minerals (Vizier et al, 1995), and hydrodynamic characteristics (Mentges et al, 2016).…”

“…Soil profile analysis also allows visualization of soil compaction and can help in collection of samples for laboratory analysis (Neves et al, 2003;Portella et al, 2012;Guimarães et al, 2013;Silva et al, 2014;Tavares Filho et al, 2014;Boizard et al, 2016). This method is an important diagnostic tool for field use, especially when studying soil compaction problems (Neves et al, 2003).…”

“…Our hypothesis is that a profile with a given sequence of structures under a given management system, classified by the profil cultural method (Tavares Filho et al, 1999;Boizard et al, 2016), may have different physical hydraulic behaviors. Thus, the aim of this study was to evaluate hydraulic conductivity and soil physical properties (soil bulk density, and macro-, micro-and total porosity) in the structures identified by the profil cultural method in Oxisol soils under two contrasting management systems (perennial pasture and sugarcane).…”