Consulta: subjectFacets:"Pedotransfer functions"
Registros recuperados: 7
Data/hora: 12/06/2024 06:44:43

PEDOFUNCTIONS APPLIED TO THE LEAST LIMITING WATER RANGE TO ESTIMATE SOIL WATER CONTENT AT SPECIFIC POTENTIALS
Provedor de dados: 70
Autores: Tavanti,Renan F. R.; Freddi,Onã da S.; Tavanti,Tauan R.; Rigotti,Adriel; Magalhães,Wellington de A.
ABSTRACT The least limiting water range (LLWR) is a soil physical quality indicator that receives much attention. It has been criticized and put to the test regarding mathematical models that compose it since they describe the behavior of soil physical attributes in a simplified way. This study aimed to assess the efficiency of some pedofunctions proposed in the literature and artificial neural networks on the accuracy in predicting soil water retention at potentials equivalent to field capacity (θFC) and permanent wilting point (θPWP). In other words, to apply the best models to LLWR of two soil types (Oxisol and Ultisol) and verify changes in their structure. The results indicated that pedofunctions using sand, silt, clay, bulk density, and soil organic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Soil physics; Soil physical quality indicator; Available water; Pedotransfer functions; Artificial neural networks.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162019000400444

Modeling and correction of soil penetration resistance for variations in soil moisture and soil bulk density
Provedor de dados: 70
Autores: Silva,Wininton M. da; Bianchini,Aloísio; Cunha,Cesar A. da.
ABSTRACT This study aimed to describe the behavior of models for adjusting data of soil penetration resistance for variations in soil moisture and soil bulk density. The study was carried out in Lucas do Rio Verde, MT, Brazil in a typic dystrophic red-yellow Latosol (Oxisol) containing 0.366 kg kg−1 of clay. Soil penetration resistance measurements were conducted in the soil moistures of 0.33 kg kg−1, 0.28 kg kg−1, 0.25 kg kg−1 and 0.22 kg kg−1. Soil penetration resistance behavior due to variations in soil moisture and soil bulk density was assessed by estimating the soil resistance values by non-linear models. There was an increase of the soil penetration resistance values as soil was losing moisture. For the same edaphic condition studied, small...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Soil compaction; Pedotransfer functions; Cone index.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162016000300449

Bulk Density Prediction for Histosols and Soil Horizons with High Organic Matter Content
Provedor de dados: 90
Autores: Beutler,Sidinei Julio; Pereira,Marcos Gervasio; Tassinari,Wagner de Souza; Menezes,Michele Duarte de; Valladares,Gustavo Souza; Anjos,Lúcia Helena Cunha dos.
ABSTRACT Bulk density (Bd) can easily be predicted from other data using pedotransfer functions (PTF). The present study developed two PTFs (PTF1 and PTF2) for Bd prediction in Brazilian organic soils and horizons and compared their performance with nine previously published equations. Samples of 280 organic soil horizons used to develop PTFs and containing at least 80 g kg-1 total carbon content (TOC) were obtained from different regions of Brazil. The multiple linear stepwise regression technique was applied to validate all the equations using an independent data set. Data were transformed using Box-Cox to meet the assumptions of the regression models. For validation of PTF1 and PTF2, the coefficient of determination (R2) was 0.47 and 0.37, mean error...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pedotransfer functions; Multiple linear regression; Box-cox transformation; Soil database.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832017000100309

Estimation of water retention and availability in soils of Rio Grande do Sul
Provedor de dados: 90
Autores: Reichert,José Miguel; Albuquerque,Jackson Adriano; Kaiser,Douglas Rodrigo; Reinert,Dalvan José; Urach,Felipe Lavarda; Carlesso,Reimar.
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 up for soil properties, including water retention: one based on literature data (725 entries) and the other with soil data from an irrigation scheduling and management system (239 entries). From the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pedotransfer functions; Texture class; Water retention curve; Mineralogy.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832009000600004

The efficiency of different estimation methods of hydro-physical limits
Provedor de dados: 90
Autores: Martínez,Emma María; Serafín Cuesta,Tomas; Cancela,Javier José.
The soil water available to crops is defined by specific values of water potential limits. Underlying the estimation of hydro-physical limits, identified as permanent wilting point (PWP) and field capacity (FC), is the selection of a suitable method based on a multi-criteria analysis that is not always clear and defined. In this kind of analysis, the time required for measurements must be taken into consideration as well as other external measurement factors, e.g., the reliability and suitability of the study area, measurement uncertainty, cost, effort and labour invested. In this paper, the efficiency of different methods for determining hydro-physical limits is evaluated by using indices that allow for the calculation of efficiency in terms of effort and...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Field capacity; Permanent wilting point; Pedotransfer functions; Water activity meter.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000600009

Estimation of the Retention and Availability of Water in Soils of the State of Santa Catarina
Provedor de dados: 90
Autores: Bortolini,Diego; Albuquerque,Jackson Adriano.
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 wilting point (PWP), and available water (AW) in soils of Santa Catarina (SC), through multiple linear regressions (MLR), artificial neural networks (ANN), and regression trees (RT), more efficiently than the current pedotransfer...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pedotransfer functions; Water retention curve; Artificial neural networks; Regression trees; Multiple linear regressions.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100424

Correction of resistance to penetration by pedofunctions and a reference soil water content
Provedor de dados: 90
Autores: Moraes,Moacir Tuzzin de; Debiasi,Henrique; Franchini,Julio Cezar; Silva,Vanderlei Rodrigues da.
The soil penetration resistance is an important indicator of soil compaction and is strongly influenced by soil water content. The objective of this study was to develop mathematical models to normalize soil penetration resistance (SPR), using a reference value of gravimetric soil water content (U). For this purpose, SPR was determined with an impact penetrometer, in an experiment on a Dystroferric Red Latossol (Rhodic Eutrudox), at six levels of soil compaction, induced by mechanical chiseling and additional compaction by the traffic of a harvester (four, eight, 10, and 20 passes); in addition to a control treatment under no-tillage, without chiseling or additional compaction. To broaden the range of U values, SPR was evaluated in different periods....
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Pedotransfer functions; Oxisol; Impact penetrometer; Soil compaction.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000600004