Análise do programa R para cálculos em física do solo.

Abstract

Determining the physical quality of the soil is important for studying soil degradation and management practices. This property requires in-depth analyses, especially those involving water transport in the soil, using models that are sometimes difficult to understand, and applications that require solving differential equations and using complex variables. Thus, using a computational tool to determine the physical quality of the soil will make the calculation more effective, in addition to supporting data analysis. In order to propose the use of a low-cost tool, this study presents an analysis and examples in the R program for calculations in soil physics. To this end, a description is presented of the R program packages for soil physics: sharpshootR, soilDB, SWATmodel, febr, soilprofile, HydroMe, soilphysics, soilwater, soiltexture and soilHyp, analyzing their ease of reproduction, exemplifying, when possible, using data provided by the authors themselves and available in the respective manuals, testing of functions that are available in the soilphysics package and new functions that will be implemented, with different data to calculate the Soil Water Retention Curve (SWRC) and the production of a booklet explaining how to reproduce the calculations for soil physics using the R program. The HydroMe and soilphysics packages are the most intuitive and the determinations are easily reproducible from the examples provided by the authors of the respective packages. Soilphysics is the most complete for soil physics, to date, allowing the user to perform several adjustments using a single package. Soiltexture has ease of data entry and soil textural class in several classification systems. Reproduction from the examples provided in the manuals was not satisfactory for the soilwater and SoilHyP packages. R is a free and open access program and the availability of this tool offers the opportunity for simple and complex calculations for soil physics that are of fundamental importance for assessing the physical and structural quality of soils. All R program codes and data used are available for reproduction on GitHub https://github.com/sousaetal.