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Temporal and spatial variability of structure dependent properties of a volcanic ash soil under pasture in southern Chile Chilean J. Agric. Res.
Dec,Dorota; Dörner,José; Balocchi,Oscar.
Prairies are a main source for livestock feeding in southern Chile. The aim of this research was to define how grazing events and natural wetting and drying cycles (WD) affect the spatial and temporal variability of the soil’s structural properties. The investigation was conducted in a Duric Hapludand, Valdivia Series. Penetration resistance (PR) and volumetric water content (WC), measured in situ, were used to prepare maps which show i) temporal (1383 to 3047 kPa for 46 to 16% WC) and spatial changes, and ii) grazing events as an important factor influencing spatial changes in PR (differences of 3421 kPa between max and min values). Grazing and WD cycles induced changes in the soil’s mechanical stability and pore functions, which indicate that...
Tipo: Journal article Palavras-chave: Penetration resistance; Water content; Mechanical strength; Porous system; Andisol.
Ano: 2011 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000200015
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LA PERMEABILIDAD DEL AIRE Y CONDUCTIVIDAD HIDRÁULICA SATURADA COMO HERRAMIENTA PARA LA CARACTERIZACIÓN FUNCIONAL DE LOS POROS DEL SUELO R.C. Suelo Nutr. Veg.
Dorner,José; Dec,Dorota.
Con el objetivo de describir los aspectos funcionales de los poros de suelos labrados, se recolectaron muestras no disturbadas en dos profundidades y orientaciones (vertical y horizontal) en suelos estructurados del Norte de Alemania. Se determinó la curva de retención de agua, la permeabilidad de aire (ka) y la conductividad hidráulica en fase saturada (k f). Se calculó la distribución de poros por tamaño, la porosidad de aire e índices de continuidad de poros. El manejo agrícola afecta al suelo cuantitativa y cualitativamente. La formación de un pie de arado implica no tan sólo una reducción del volumen de poros sino que también causa una dependencia espacial de las propiedades hidráulicas del suelo a través de la formación de una estructura laminar. Con...
Tipo: Journal article Palavras-chave: Permeabilidad del aire; Porosidad del suelo; Continuidad de poros.
Ano: 2007 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912007000200001
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EFFECT OF SOIL MANAGEMENT ON THEIR THERMAL PROPERTIES R.C. Suelo Nutr. Veg.
Dec,Dorota; Dörner,José; Horn,Rainer.
In order to determine the effect of soil management on its thermal properties, undisturbed soil samples were taken from two tillage treatments (conventional and conservation treatment) at two depths (0-30cm and 30-60cm) of a Stagnic Luvisol (silt loam) before and after directly wheeling. The experimental field, located in Harste/Goettingen, Germany, was cultivated with sugar beet (Beta vulgaris). To calculate thermal properties of the soil, the volumetric water content (TDR needles) and temperature (pT 100 thermistors) during the simulation of the daily fluctuation of temperature were registered in laboratory and then the thermal conductivity, volumetric heat capacity and heat diffusivity were calculated following the damping depth method and the...
Tipo: Journal article Palavras-chave: Heat capacity; Heat conductivity; Thermal diffusivity; Tillage system.
Ano: 2009 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912009000100003
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EFFECT OF BULK DENSITY ON HYDRAULIC PROPERTIES OF HOMOGENIZED AND STRUCTURED SOILS R.C. Suelo Nutr. Veg.
Dec,Dorota; Dorner,José; Becker-Fazekas,Orsolya; Horn,Rainer.
In order to determine the effect of bulk density and soil structure on their hydraulic behaviour, undisturbed samples were collected and disturbed samples were prepared from a Luvisol. The experimental field, located in Harste/Goettingen, Germany, was cultivated with sugar beet (Beta vulgaris). The water retention curve (WRC) and saturated hydraulic conductivity (Ks) were measured on undisturbed samples and homogenized samples prepared at different bulk densities (1.2 -1.4 and 1.6 Mg m-3). To determine the effect of soil shrinkage on the unsaturated hydraulic conductivity (k/Ψ) ,the vertical deformation of the repacked samples was measured and relative water content differences (dθ)were determined. The hydraulic properties of soils with...
Tipo: Journal article Palavras-chave: Water retention curve; Soil shrinkage; Soil structure.
Ano: 2008 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912008000100001
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EFECTO DEL CAMBIO DE USO EN LA ESTABILIDAD DE LA ESTRUCTURA Y LA FUNCIÓN DE LOS POROS DE UN ANDISOL (TYPIC HAPLUDAND) DEL SUR DE CHILE R.C. Suelo Nutr. Veg.
Dörner,José; Dec,Dorota; Peng,Xinhua; Horn,Rainer.
Los suelos volcánicos del sur de Chile constituyen cerca del 60% del suelo arable del país. Estos suelos se encuentran bajo un amplio rango de usos desde sistemas prístinos hasta otros con un uso intensivo. El objetivo de este trabajo fue determinar el efecto del cambio de uso de suelo sobre: i) la estabilidad del suelo frente a presiones externas e internas; ii) la conductividad hidráulica y iii) su resiliencia funcional. Muestras disturbadas y no disturbadas de suelo fueron recolectadas a 5, 20, 40 cm de profundidad en un suelo Andisol (Typic Hapludand) bajo un renoval de bosque nativo (NF), una pradera de 50 años (P50) y otra de 1 año de uso (Pl). Se determinó la curva de retención de agua, contracción y consolidación, la conductividad hidráulica...
Tipo: Journal article Palavras-chave: Andisol; Propiedades estructurales; Función de los poros.
Ano: 2009 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912009000300003
Registros recuperados: 5
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