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41 results

Hydrostatic Equilibrium between Soil Samples and Pressure Plates Used in Soil Water Retention Determination: Consequences of a Questionable Assumption

Quirijn de Jong van Lier ORCID logo , Everton Alves Rodrigues Pinheiro ORCID logo , Leonardo Inforsato ORCID logo

23/Jul/2019

ABSTRACT Soil water retention is among the soil hydraulic properties most routinely measured in studies of soil physics and related areas. This property is used in dynamic simulations of vadose zone processes such as soil water availability, surface boundary processes of evaporation and infiltration, and the fate of soil pollutants. The most common measurement technique consists in establishing a hydrostatic equilibrium between an initially saturated soil sample and a porous medium at a certain tension on a tension table or […]

Performance of the Groenevelt and Grant Model for Fitting Soil Water Retention Data from Brazilian Soils

Robson André Armindo ORCID logo , Quirijn de Jong van Lier ORCID logo , Maria Eliza Turek ORCID logo , Aline Mari Huf dos Reis ORCID logo , Marina Luciana Abreu de Melo ORCID logo , Maria Elisa Palma Ramos ORCID logo , [...]

17/Jul/2019

ABSTRACT The soil water retention curve (SWRC) is essential for vadose zone hydrological modeling and related applications. In 2004, Groenevelt and Grant (GRT) presented a mathematical model for describing the SWRC and reported its mathematical versatility and good fit to soils from a Dutch database. In order to evaluate the application of GRT to SWRCs of Brazilian soils, we aimed to analyze the performance of GRT for 72 soils from Brazil. Besides that, the obtained results with GRT for these […]

Visual Abstract

Comparison of the Casagrande and Fall Cone Methods for Liquid Limit Determinations in Different Clay Soils

Letícia Garcia Crevelin ORCID logo , Kátia Vanessa Bicalho ORCID logo

02/Jul/2019

ABSTRACT The liquid limit (LL) is an important parameter for soil classification systems. The use of the cone penetrometer technique for measuring the liquid limit is an attractive alternative method since the percussion method is highly operator dependent. In this article, the importance of specifying the procedure and equipment used to determine the LL of a clay soil is highlighted using LL test results conducted on different clay soils. The results of LL, obtained by the percussion method proposed by […]

Stability of Soil Moisture Patterns Retrieved at Different Temporal Resolutions in a Tropical Watershed

Luís Romero Barbosa ORCID logo , Nicholas Borges de Lira ORCID logo , Victor Hugo Rabelo Coelho ORCID logo , Alain Marie Bernard Passerat de Silans ORCID logo , André Nóbrega Gadêlha ORCID logo , Cristiano das Neves Almeida ORCID logo

19/Jun/2019

ABSTRACT Above and underground hydrological processes depend on soil moisture (SM) variability, driven by different environmental factors that seldom are well-monitored, leading to a misunderstanding of soil water temporal patterns. This study investigated the stability of the SM temporal dynamics to different monitoring temporal resolutions around the border between two soil types in a tropical watershed. Four locations were instrumented in a small-scale watershed (5.84 km2) within the tropical coast of Northeast Brazil, encompassing different soil types ( Espodossolo Humilúvico […]

Visual Abstract

Estimation of the Retention and Availability of Water in Soils of the State of Santa Catarina

Diego Bortolini, Jackson Adriano Albuquerque

02/Nov/2018

ABSTRACT: Soil water retention and availability are important properties for agricultural production, which can be measured directly or estimated by pedotransfer functions. Some studies on this topic were carried out in Santa Catarina, Brazil. To improve the estimates, it is necessary to evaluate other properties, to analyze more soil types, as well as to use other analysis techniques such as artificial neural networks and regression trees. Thus, the objective of the study was to estimate the field capacity (FC), permanent […]

Determining the In Situ Apparent Thermal Diffusivity of a Sandy Soil

Oscar Fernando Silva Aguilar, Jorge Alberto Andaverde Arredondo, Beatris Adriana Escobedo Trujillo, Artemio Jesús Benitez Fundora

02/Nov/2018

ABSTRACT: The thermal wave amplitude method is used to determine soil thermal diffusivity in situ for a sandy soil in Mexico (Coatzacoalcos, Veracruz). Soil diurnal temperature fluctuations were measured from depths of 0.05 to 0.65 m, in 0.01 m increments, during the months of April and August. Five mean diffusivity values were obtained experimentally, corresponding to the different depths combination. The soil thermal diffusivity ranged between 2.26 × 10−7 and 8.71 × 10−7 m2 s−1. The diffusivity values obtained are […]

Soil Water Retention Curve as Affected by Sample Height

Maria Laiane do Nascimento Silva, Paulo Leonel Libardi, Fernando Henrique Setti Gimenes

02/Nov/2018

ABSTRACT: The soil water retention curve is one of the main instruments to assess the soil physical quality and to improve soil management. Traditionally, the equipment most used in the laboratory to determine the retention curve has been Haines funnels and Richards chambers. An important factor to which little attention has been given in the use of these equipaments is the height of the undisturbed soil sample. This work proposes to evaluate the influence of different heights of undisturbed samples […]

An Alert Regarding a Common Misinterpretation of the Van Genuchten α Parameter

Quirijn de Jong van Lier, Everton Alves Rodrigues Pinheiro

18/Jun/2018

ABSTRACT Among the equations available to describe the relation between matric potential and soil water content, the soil water retention function, the most commonly used is the equation proposed by Van Genuchten in his 1980 landmark paper. In soil physics literature, especially in Brazil, several authors relate the inverse of the Van Genuchten parameter α to the air-entry pressure. This study aimed to show this common interpretation to be erroneous, as 1/α corresponds to water contents lower than saturation. The […]

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 […]

Visual Evaluation of the Soil Structure under Different Management Systems in Lowlands in Southern Brazil

Ivana Kruger Tuchtenhagen, Cláudia Liane Rodrigues de Lima, Adilson Luís Bamberg, Rachel Muylaert Locks Guimarães, Pulido-Moncada Mansonia

20/Apr/2018

ABSTRACT The “Visual Evaluation of Soil Structure” (VESS) is a method used primarily to evaluate the soil structural quality of Oxisols in Brazil and secondly for more specific research, consultancy, and teaching purposes. Since the methodology was never applied and compared with laboratory evaluations of physical properties of hydromorphic soils of the Pampa biome in the south of Brazil, this study evaluated the use of VESS as a visual indicator of the structure quality of a typic eutrophic Albaqualf soil […]

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