Consulta: subjectFacets:"Available water"
Registros recuperados: 9
Data/hora: 10/06/2024 01:19:28

PEDOFUNCTIONS APPLIED TO THE LEAST LIMITING WATER RANGE TO ESTIMATE SOIL WATER CONTENT AT SPECIFIC POTENTIALS
Provedor de dados: Engenharia Agrícola
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

Soil water potential during different phenological phases of coffee irrigated by center pivot
Provedor de dados: Engenharia Agrícola
Autores: Evangelista,Adão W. P.; Lima,Luiz A.; Silva,Antônio C. da; Martins,Carla de P.; Ribeiro,Moisés S.
Irrigation management can be established, considering the soil water potential, as the limiting factor for plant growth, assuming the soil water content between the field capacity and the permanent wilting point as available water for crops. Thus, the aim of this study was to establish the soil water potential interval during four different phenological phases of coffee irrigated by center pivot. The experiment was set at the experimental area of the Engineering Department at the Federal University of Lavras, in Brazil. The coffee variety planted is designated as Rubi, planted 0.8 meters apart, with rows spaced 3.5 meters apart. The treatments corresponded to the water depths applied based on different percentages of Kc and reference evapotranspiration...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Irrigated coffee; Available water; Coffea arabica L.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162013000200006

Effect of soil-water tension on herbaceous cotton yield
Provedor de dados: Pesquisa Agropecuária Brasileira
Autores: Oliveira,Francisco Assis de; Campos,Tarcísio Gomes da Silva; Oliveira,Bernardete Campos.
A field experiment was conducted during two years, 1990/91, in an alluvial soil, in the State of Paraíba, Brazil, to study the effect of the levels of soil-water tension, 50, 100, 200, 300, 400 and 600 kPa, at 20 cm depth, on upland cotton (Gossypium hirsutum L.r. latifolium Hutch, cv. CNPA-6H) yield. The experimental design was a complete randomized block with six treatments and four repetitions. There was an effect of the treatments on plant height, leaf area index and cotton yield, but the precocity index was not modified. Water should be applied when the soil-water tension, measured at 20 cm depth, reaches values around 200 kPa. There was a quadratic (R² = 0.893**) response of cotton yields to soil water tension, with the maximum when water was applied...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Gossypium hirsutum; Available water; Irrigation.
Ano: 1999
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X1999001000018

Evaluation of almond shell as a culture substrate for ornamental plants. I. Characterisation: (with 4 figures &amp;#38; 6 tables)
Provedor de dados: Phyton: Revista Internacional de Botánica Experimental
Autores: Lao,MT; Jiménez,S.
Some technical and economic problems currently limit the use of substrates. The main problems include the lack of reciprocal adaptation of the cultivation technics and the substrate, the possible presence of pathogens, and the cost involved. To these we must add the ecological problems of the extraction areas, since there are no short-term renewable resources, especially in the case of peat, the classic substrate. This has motivated the search for substitutes, especially amongst indigenous materials and those easily obtained locally, such as cereals straw, rice husk and cork residues. The use of these substrates should be evaluated agronomically for: physical (total porosity, available water, air content, distribution of particles size, apparent density),...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Substrate characterisation; Available water; Peat; Expanded clay.
Ano: 2004
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-56572004000100007

Does the Introgression of Bt Gene Affect Physiological Cotton Response to Water Deficit?
Provedor de dados: Planta Daninha
Autores: ROSOLEM,C.A.; SARTO,M.V.M.; ROCHA,K.F.; MARTINS,J.D.L.; ALVES,M.S.
ABSTRACT: Water deficit may affect the expression of lepidoptera-controlling proteins in cotton. However, it is unknown if there is a differential response of conventional and Bt cotton cultivars to water deficit, what could potentially affect the plant competition with weeds. The objective of this work was to investigate the response of Bt cotton cultivars to water deficit compared with their conventional near-isolines. The experiment was conducted in a greenhouse, where the cotton cultivars FMT 705, FMT 709 and IMACD 8276, with and without the Bt gene, were grown under two water regimens: 100% and 50% (moderate water deficit) of available soil water. Cotton phenology was severely affected by moderate water deficit, with a reduction in shoot and root dry...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Available water; Drought; Gossypium hirsutum L.; Genetically Modified Organism.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582019000100234

Yield and water use of cherry tomato under water availability and potassium doses
Provedor de dados: Revista Brasileira de Engenharia Agrícola e Ambiental
Autores: Pacheco,Adriano B.; Silva,Tonny J. A. da; Bonfim-Silva,Edna M.; Castro,Hamilton A. W.; Koetz,Marcio.
ABSTRACT The objective of this study was to evaluate the yield and water use of cherry tomatoes under soil water availability and potassium (K) doses in a greenhouse. The experiment was conducted in randomized blocks in a 52 fractional factorial design, corresponding to five levels of water availability and five K doses, with 13 combinations (4-0; 4-250; 4-500; 14-125; 14-375; 24-0; 24-250; 24-500; 34-125; 34-375; 44-0; 44-250; 44-500) (kPa-mg dm-3) and four replicates. A drip irrigation system with semi-automated irrigation control was used. The analyzed variables were shoot dry matter, number of fruits, yield, water consumption and water use efficiency. Highest cherry tomato yield occurs at soil water tension of 24 kPa and K dose of 290 mg dm-3. Soil...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Lycopersicon esculentum Mill.; Available water; Potassium fertilization.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000500326

Least limiting water range and physical quality of soil under groundcover management systems in citrus
Provedor de dados: Scientia Agricola
Autores: Fidalski,Jonez; Tormena,Cássio Antonio; Silva,Álvaro Pires da.
Machinery-based farming operations used for perennial fruit crops often damage soils, particularly if the soil is wet and prone to compaction. We hypothesized that perennial vegetation growing in the interrows of orange orchards can mitigate the soil physical degradation from machinery traffic. The objective of this study was to investigate the effects of different groundcover management systems on the soil physical quality indicators including the least limiting water range (LLWR). An experiment was started in 1993 in a Typic Paleudult to evaluate three groundcover management systems: Bahia grass (Paspalum notatum) with mowing, perennial peanut (Arachis pintoi), and natural regrowth in which weeds were controlled by herbicide. The experimental design was...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Organic carbon; Soil compaction; Bulk density; Resistance to penetration; Available water.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162010000400012

Comparison between climatological and field water balances for a coffee crop
Provedor de dados: Scientia Agricola
Autores: Bruno,Isabeli Pereira; Silva,Adriana Lúcia da; Reichardt,Klaus; Dourado-Neto,Durval; Bacchi,Osny Oliveira Santos; Volpe,Clóvis Alberto.
The use of climatological water balances in substitution to complete water balances directly measured in the field allows a more practical crop management, since the climatological water balances are based on data monitored as a routine. This study makes a comparison between these methods in terms of estimatives of evapotranspiration, soil water storage, soil available water, runoff losses, and drainage below root zone, during a two year period, taking as an example a coffee crop of the variety Catuaí, three to five years old. Climatological water balances based on the estimation of the evapotranspiration through the methods of Thornthwaite and Penman-Monteith, can reasonably substitute field measured balances, however underestimating the above mentioned...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Evapotranspiration; Soil water storage; Available water; Water deficit; Water excess.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162007000300001

Limites na utilização de um modelo de balanço hídrico decendial em função da capacidade de água disponível no solo - DOI: 10.4025/actasciagron.v30i2.1721
Provedor de dados: Acta Scientiarum: Agronomy
Autores: Souza Filho, Jorge Luiz Moretti de; UFPR; Gomes, Siguifrid; UFPR.
O presente trabalho consistiu na avaliação dos limites de utilização de um modelo de simulação do balanço hídrico climatológico decendial irrigacionista, em quatro regiões distintas no Estado do Paraná. Nas análises, 68 cenários de simulação do balanço hídrico foram testados para permitir o relacionamento entre a evapotranspiração da cultura (ETc), chuva provável a 75%, diferentes capacidades de água disponível no solo (CAD) e deficiência hídrica anual (DEF). As análises realizadas mostraram que: o modelo consegue obter melhores estimativas de seus componentes para maiores valores de água disponível (AD) no solo; o valor ideal de CAD para processar as análises de irrigação em função das variações da ETo, Kc e ETc deve de preferência ser estabelecida no...
Palavras-chave: 5.00.00.00-4    Ciências Agrárias simulação; CAD; Água disponível; Irrigação; Agricultura irrigada 5.00.00.00-4    Ciências Agrárias simulation; AWC; Available water; Irrigation; Agricultural irrigation.
Ano: 2008
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/1721