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All publications of “Paulo Ivonir Gubiani”

5 results

Tipping Bucket Prototype for Automatic Quantification of Surface Runoff Rate in Plots

André Somavilla, Paulo Ivonir Gubiani ORCID logo , Anderson Luiz Zwirtz

07/Jan/2019

ABSTRACT: Quantification of runoff rate is an onerous task with non-automated devices; it requires a lot of manual labor to perform measurements. In this study, an automatic device to quantify the surface runoff rate from plots with a small area was developed and tested. The prototype was based on the tipping bucket technique and built with reused materials. Its performance was tested in the laboratory and a calibration curve was developed to improve measurement accuracy. The device can be used […]

Transpiration Reduction Factor and Soybean Yield in Low Land Soil with Ridge and Chiseling

Paulo Ivonir Gubiani, Eduardo Augusto Müller, André Somavilla, Anderson Luiz Zwirtes, Rodrigo Pivoto Mulazzani, Enio Marchesan

10/May/2018

ABSTRACT Water and oxygen deficiencies in the soybean crop cultivated on lowland soils are an important topic of research. The objective of this study was to investigate changes in water and oxygen supply and soybean yield caused by soil management in lowland soils. A soybean crop was grown under four soil conditions: no-tillage (NT), chiseling (CH), ridge tillage on no-tillage (NTR), and ridge tillage on chiseling (CHR). Soil bulk density, total porosity, macro- and microporosity, air permeability, and saturated hydraulic […]

Rheological Parameters as Affected by Water Tension in Subtropical Soils

Patricia Pértile, José Miguel Reichert, Paulo Ivonir Gubiani, Dörthe Holthusen, André da Costa

06/Jun/2016

ABSTRACT Rheological parameters have been used to study the interaction between particles and the structural strength of soils subjected to mechanical stresses, in which soil composition and water content most strongly affect soil resistance to deformation. Our objective was to evaluate the effect of water tension on rheological parameters of soils with different mineralogical, physical, and chemical composition. Surface and subsurface horizons of four Oxisols, two Ultisols, one Alfisol, and one Vertisol were physically and chemically characterized; their rheological parameters […]

BEYOND THE “LEAST LIMITING WATER RANGE”: RETHINKING SOIL PHYSICS RESEARCH IN BRAZIL

Quirijn de Jong van Lier, Paulo Ivonir Gubiani

01/Jul/2015

As opposed to objective definitions in soil physics, the subjective term “soil physical quality” is increasingly found in publications in the soil physics area. A supposed indicator of soil physical quality that has been the focus of attention, especially in the Brazilian literature, is the Least Limiting Water Range (RLL), translated in Portuguese as “Intervalo Hídrico Ótimo” or IHO. In this paper the four limiting water contents that define RLL are discussed in the light of objectively determinable soil physical […]

RELATIONSHIP BETWEEN BULK DENSITY AND WATER CONTENT OF AN OXISOL SUBJECTED TO REPEATED CYCLES OF EXPANSION AND CONTRACTION

Paulo Ivonir Gubiani, Quirijn de Jong Van Lier, Marta Sandra Drescher, Henrique Caletti Mezzomo, Camila Machado Costa Veiga

01/Jan/2015

Soil compaction is an undesirable consequence of land use for crop production, especially under cultivation with minimum soil turnover as in the no-tillage system (NTS). However, the compaction caused by machine traffic on soils under NTS does not make crop production unviable, indicating that some intrinsic mechanisms promote the reversion of soil compaction. In this study, the influence of alternate contraction and expansion cycles was evaluated with regard to the bulk density (ρ) of a Latossolo Vermelho argiloso (clayey Oxisol) […]