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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 […]

Soil Physical Quality and Soybean Yield as Affected by Chiseling and Subsoiling of a No-Till Soil

Luis Alberto Lozano, Carlos Germán Soracco, Rafael Villarreal, Juan M. Ressia, Guillermo O. Sarli, Roberto Raúl Filgueira

13/Apr/2016

ABSTRACT The concept of soil physical quality (SPQ) is currently under discussion, and an agreement about which soil physical properties should be included in the SPQ characterization has not been reached. The objectives of this study were to evaluate the ability of SPQ indicators based on static and dynamic soil properties to assess the effects of two loosening treatments (chisel plowing to 0.20 m [ChT] and subsoiling to 0.35 m [DL]) on a soil under NT and to compare the […]

Evaluation of physical quality indices of a soil under a seasonal semideciduous forest

Thalita Campos Oliveira, Laura Fernanda Simões da Silva, Miguel Cooper

01/Apr/2014

The concept of soil quality is currently the subject of great discussion due to the interaction of soil with the environment (soil-plant-atmosphere) and practices of human intervention. However, concepts of soil quality relate quality to agricultural productivity, but assessment of soil quality in an agronomic context may be different from its assessment in natural areas. The aim of this study was to assess physical quality indices, the S index, soil aeration capacity (ACt/Pt), and water storage capacity (FC/Pt) of the […]

Revisiting the S-index for soil physical quality and its use in Brazil

Quirijn de Jong van Lier

01/Feb/2014

The S-index was introduced in 2004 in a publication by A.R. Dexter. S was proposed as an indicator of soil physical quality. A critical value delimiting soils with rich and poor physical quality was proposed. At present, Brazil is world leader in citations of Dexter’s publication. In this publication the S-theory is mathematically revisited and extended. It is shown that S is mathematically correlated to bulk density and total porosity. As an absolute indicator, the value of S alone has […]

Influence of sand fractions on water retention and availability in Caiuá and Paranavaí sandstone formations

Jonez Fidalski, Cássio Antonio Tormena, Sérgio José Alves, Pedro Antonio Martins Auler

01/Jun/2013

It has been found that the results of the land use and management techniques adopted for soils derived from Caiuá sandstone in the Northwest of Paraná are not always satisfactory in terms of crop yields. In this region, sandstone occurs in two forms: the Caiuá and Paranavaí Formations, with differences in soil particle size. We hypothesized that the water retention and availability for agricultural production is lower in the Caiuá soils, due to the higher proportion of coarse sand than […]

Least limiting water range in a typic haplorthox after the first continuous grazing period of brachiaria ruziziensis in integrated crop-livestock system

Jonez Fidalski, Cássio Antonio Tormena, Sérgio José Alves

01/Jun/2013

The least limiting water range (LLWR) is one of the best indicators of soil physical quality in intensive production systems. The objective of this study was to evaluate the physical quality of a Typic Haplorthox by the LLWR after three crop growing seasons and the first year of crop-livestock integration in Xambrê, northwestern Paraná, Brazil. The experiment was established in a randomized block design with three replications. Treatments consisted of four brachiaria heights before grazing (0.10; 0.20; 0.30, and 0.40 […]

Use of the S-index to evaluate soil physical quality

Celsemy Eleutério Maia

01/Dec/2011

Nowadays the concept of soil physical quality is well-established, based mainly on the indices that quantify soil quality. The S index is a new indicator of soil physical quality related to important soil characteristics. The purpose of this study was to evaluate the method of obtaining the S index and the derivative of the function of the of water retention curve, using the transformation ln(h) or not, and assess the problem of units and the restriction m = 1 – […]

Determination of soil hydraulic properties using polymer tensiometers in evaporation experiments

Angelica Durigon, Quirijn de Jong van Lier

01/Aug/2011

The polymer tensiometer is a newly developed instrument to measure soil water pressure heads from saturation conditions to drier than the permanent wilting point. In this note we describe how the hydraulic properties of disturbed soil samples were determined in laboratory evaporation experiments with these polymer tensiometers. Soil material from the surface layer of an Ultisol was used. The relation among hydraulic conductivity, water content and pressure heads in the range from -1 to -150 m could be determined using […]

Estimation of water retention and availability in soils of Rio Grande do Sul

José Miguel Reichert, Jackson Adriano Albuquerque, Douglas Rodrigo Kaiser, Dalvan José Reinert, Felipe Lavarda Urach, Reimar Carlesso

01/Dec/2009

Dispersed information on water retention and availability in soils may be compiled in databases to generate pedotransfer functions. The objectives of this study were: to generate pedotransfer functions to estimate soil water retention based on easily measurable soil properties; to evaluate the efficiency of existing pedotransfer functions for different geographical regions for the estimation of water retention in soils of Rio Grande do Sul (RS); and to estimate plant-available water capacity based on soil particle-size distribution. Two databases were set […]

Characterization of soil structure and porosity under long-term conventional tillage and no-tillage systems

João Tavares Filho, Daniel Tessier

01/Dec/2009

Different management systems tend to modify soil structure and porosity over the years. The aim of this study was to study modifications in the morphostructure and porosity of dystroferric Red Latosol (Oxisol) under conventional tillage and no-tillage over a 31- year period. The study began with the description of soil profiles based on the cropping profile method, to identify the most compact structures, define sample collection points for physical and chemical analysis, and determine the water retention curve. A forest […]

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