Consulta: subjectFacets:"Time domain reflectometry"
Registros recuperados: 6
Data/hora: 02/06/2024 13:45:03

Evapotranspiration and crop coefficient for potato in organic farming
Provedor de dados: 70
Autores: Carvalho,Daniel F. de; Silva,Dione G. da; Rocha,Hermes S. da; Almeida,Wilk S. de; Sousa,Eraldo da S.
The aim of this study was to quantify the water consumption and the crop coefficients (Kc) for the potato (Solanum tuberosum L.), in Seropédica, Rio de Janeiro (RJ), Brazil, under organic management, and to simulate the crop evapotranspiration (ETc) using the Kc obtained in the field and the ones recommended by the Food and Agriculture Organization (FAO). The water consumption was obtained through soil water balance, using TDR probes installed at 0.15m and 0.30m deep. At the different stages of development, the Kc was determined by the ratio of ETc and reference evapotranspiration, obtained by Penman-Monteith FAO 56. The crop coefficients obtained were 0.35, 0.45, 1.29 and 0.63. The accumulated ETc obtained in the field was 109.6 mm, while the ETc...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Solanum tuberosum L.; Time domain reflectometry; Irrigation.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000100020

Sampling and TDR probe insertion in the determination of the volumetric soil water content
Provedor de dados: 90
Autores: Teixeira,W. G.; Schroth,G.; Marques,J. D.; Huwe,Bernd.
Volumetric soil water content (theta) can be evaluated in the field by direct or indirect methods. Among the direct, the gravimetric method is regarded as highly reliable and thus often preferred. Its main disadvantages are that sampling and laboratory procedures are labor intensive, and that the method is destructive, which makes resampling of a same point impossible. Recently, the time domain reflectometry (TDR) technique has become a widely used indirect, non-destructive method to evaluate theta. In this study, evaluations of the apparent dielectric number of soils (epsilon) and samplings for the gravimetrical determination of the volumetric soil water content (thetaGrav) were carried out at four sites of a Xanthic Ferralsol in Manaus - Brazil. With the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Amazon; Oxisols; Time domain reflectometry; Dieletric properties.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832003000400001

Availability of soil water under tillage systems, mulch management and citrus rootstocks
Provedor de dados: 90
Autores: Fidalski,Jonez; Auler,Pedro Antonio Martins; Beraldo,José Marcos Garrido; Marur,Celso Jamil; Faria,Rogério Teixeira de; Barbosa,Graziela Moraes de Cesare.
The increased availability of soil water is important for the management of non-irrigated orange orchards. The objective of this study was to evaluate the availability of soil water in a Haplorthox (Rhodic Ferralsol) under different tillage systems used for orchard plantation, mulch management and rootstocks in a "Pêra" orange orchard in northwest Paraná, Brazil. An experiment in a split-split-plot design was established in 2002, in an area cultivated with Brachiaria brizantha grass in which three tillage systems (no tillage, conventional tillage and strip-tillage) were used for orchard plantation. This grass was mowed twice a year between the rows, representing two mulch managements in the split plots (no mulching and mulching in the plant rows). The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Brachiaria brizantha; No tillage; Soil management; Soil texture; Time domain reflectometry.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832010000300033

Estimation of water percolation by different methods using TDR
Provedor de dados: 90
Autores: Silva,Alisson Jadavi Pereira da; Coelho,Eugênio Ferreira.
Detailed knowledge on water percolation into the soil in irrigated areas is fundamental for solving problems of drainage, pollution and the recharge of underground aquifers. The aim of this study was to evaluate the percolation estimated by time-domain-reflectometry (TDR) in a drainage lysimeter. We used Darcy's law with K(θ) functions determined by field and laboratory methods and by the change in water storage in the soil profile at 16 points of moisture measurement at different time intervals. A sandy clay soil was saturated and covered with plastic sheet to prevent evaporation and an internal drainage trial in a drainage lysimeter was installed. The relationship between the observed and estimated percolation values was evaluated by linear regression...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Internal drainage; Unsaturated hydraulic conductivity; Instantaneous profile; Time domain reflectometry.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000100007

Calibration of a soil moisture sensor with disturbed and undisturbed soil samples from Bahia
Provedor de dados: 91
Autores: Lima,João G. A.; Oliveira,Aureo S. de; Souza,Luciano da S.; Silva,Neilon D. da; Viana,Paula C.
ABSTRACT The objective of this study was to evaluate the models proposed by manufacturers and in the literature with respect to soil moisture measurement and to evaluate the performance of the CS616 sensor in the calibration of disturbed and undisturbed soil samples. These calibrations were performed using linear and quadratic models. Disturbed samples were collected in São Gabriel/BA, six samples placed in pots, whereas undisturbed samples were collected in Cruz das Almas/BA, three samples directly collected in the area and placed in a container. A calibration was performed between 21/12/2016 and 08/01/2017. The models proposed in the literature and by manufacturers differed in the estimation of volumetric soil moisture. Disturbed soil samples had higher...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Soil water content; Time domain reflectometry; Soil physics.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018001000696

Spatial behaviour of soil moisture in the root zone of the Caatinga biome
Provedor de dados: 124
Autores: Costa,Carlos Alexandre Gomes; Lopes,José Wellington Batista; Pinheiro,Everton Alves Rodrigues; Araújo,José Carlos de; Gomes Filho,Raimundo Rodrigues.
The purpose of this study was to represent the soil moisture in the profile corresponding to the root zone from TDR sensors in a preserved area of the Caatinga biome and analyze the spatialized moisture adjustment equations under different layers of the soil profile. For that, we analyzed three classes of soil (red yellow Ultisol; Hypochromic Luvisol; Udorthent) in the Aiuaba Experimental Watershed, located in the semiarid zone of northeastern Brazil. The hydro-physical parameters representing the soil water retention (field capacity, wilting point and residual moisture) were collected in four campaigns, in six points and in the profiles corresponding to the effective root depth, totaling 216 samples. For the evaluation of the regression models, we used...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Caatinga; Soil; Time domain reflectometry.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902013000400004