Measurement of soil water tension in single aggregates with use of the filter paper method

In order to analyze the hydraulic properties of municipal solid waste (MSW), laboratory tests on the soil-water characteristic curves of 6 groups of MSW samples with different void ratios and organic contents are performed by means of the unsaturated consolidation apparatus. The filter paper method is also employed to determine their soil-water characteristic curves. The distribution indexλof void size of the samples is analyzed. The results show that the air-entry value of the MSW samples is very small and about 1kPa, and it increases owing to the action of loading. The value ofλ decreases with the increase of the initial void ratio and increases with the increase of the organic content in the samples. For measuring the soil-water characteristic curves of MSW by means of the filter paper method, the values at high suction phase are more rational and significant.

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Comparison between Soil-Water Characteristic Curves based on filter paper method and grain-size distribution/volume-mass prediction: An evaluation of input data stemmed from hydrometer and Cilas grain-size analyser

E3S Web of Conferences ◽

10.1051/e3sconf/202019503027 ◽

2020 ◽

Vol 195 ◽

pp. 03027

Author(s):

Marcos Felipe da Silva André ◽

Thiago de Souza Carnavale

Keyword(s):

Grain Size ◽

Size Distribution ◽

Soil Water ◽

Grain Size Distribution ◽

Filter Paper ◽

Input Data ◽

Characteristic Curves ◽

Filter Paper Method ◽

Soil Water Characteristic Curves ◽

Paper Method

The current paper aims to present a comparison between soil-water characteristic curves based on the filter paper method and on a volume-mass estimation. Additionally, this research consists in comparing grain size distributions by sieving/hydrometer and by sieving/Cilas (particle-size analyser model 1092), when it comes to determining the soil-water characteristic curves by a volume-mass prediction on the Soil Vision software. As materials, were used two sets of colluvial soils sampled at the Campus Quinta do Paraiso -Centro Universitário Serra dos Órgãos (UNIFESO), Teresópolis – Brazil. The results showed that the soil-water characteristic curves related to the filter paper method or grain size distribution estimation are different. However, the tests performed by sieving/Cilas are more efficient than the results based on sieving/hydrometer, concerning its uses as input data for soil-water characteristic curves estimations. In conclusion, even considering the estimation method was not able to depict the same results such as obtained by the filter paper method, the use of Cilas is a procedure that can improve the quality of the predicted soil-water characteristic curve.

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Citrus Carbohydrate Levels were Related to Irrigation Frequency but Not Arbuscular Mycorrhizal Fungal (AMF) Inoculum

HortScience ◽

10.21273/hortsci.33.3.498a ◽

1998 ◽

Vol 33 (3) ◽

pp. 498a-498

Author(s):

Matthew W. Fidelibus ◽

Chris A. Martin

Keyword(s):

Soil Water ◽

Arbuscular Mycorrhizal ◽

Irrigation Frequency ◽

Soil Water Tension ◽

Root Starch ◽

Carbohydrate Levels ◽

Amf Communities ◽

Sugar Levels ◽

Shoot Mass ◽

Water Tension

Sugar and starch concentrations in leaves and roots of Citrus volkameriana Tan and Pasq were measured in response to irrigation frequency and AMF inoculum. Non-mycorrhizal seedlings were treated with a soil inoculum from one of five different communities of AMF; two AMF communities from Arizona citrus orchard soils, and three communities from undisturbed desert soils. Plants were assigned to frequent (soil water tension > –0.01 MPa) or infrequent (soil water tension > –0.06 MPa) irrigation cycles and were container-grown in a glasshouse for 4 months before tissues were analyzed. Fungal inoculum source did not affect shoot or root carbohydrate levels. Plants grown under high irrigation frequency had increased leaf and root starch levels and increased root sugar levels compared with those under low irrigation frequencies. High irrigation frequency also increased shoot mass.

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Evaluation of Very High Soil-Water Tension Threshold Values in Sensor-Based Deficit Irrigation Systems

Journal of Irrigation and Drainage Engineering ◽

10.1061/(asce)ir.1943-4774.0000722 ◽

2014 ◽

Vol 140 (9) ◽

Cited By ~ 6

Author(s):

Sebastian Kloss ◽

Niels Schütze ◽

Urs Schmidhalter

Keyword(s):

Soil Water ◽

Deficit Irrigation ◽

Threshold Values ◽

Irrigation Systems ◽

Soil Water Tension ◽

High Soil ◽

Water Tension ◽

Very High

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Effects of Irrigation Regimes on Yield and Water Use by Sweetpotato

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.115.5.712 ◽

1990 ◽

Vol 115 (5) ◽

pp. 712-714 ◽

Cited By ~ 5

Author(s):

Doyle A. Smittle ◽

Melvin R. Hall ◽

James R. Stansell

Keyword(s):

Water Stress ◽

Soil Water ◽

Water Use ◽

Ipomoea Batatas ◽

Regression Equations ◽

Marketable Yield ◽

Water Regimes ◽

Soil Water Tension ◽

Water Tension ◽

Storage Root Development

Sweetpotatoes [Ipomoea batatas (L.) Lam cv. Georgia Jet] were grown on two soil types in drainage lysimeters under controlled soil water regimes during 1982 and 1983. Water regimes consisted of irrigating the sweetpotatoes throughout growth when soil water tension at 23 cm exceeded 25, 50, or 100 kPa or by allowing a 100-kPa water stress before root enlargement, during early root enlargement, or throughout root enlargement. Water use and marketable yields were greater when sweetpotatoes were grown on a Tifton loamy sand (fine loamy, siliceous, thermic, Plinthitic Paleudult) than when grown on a Bonifay sand (loamy, siliceous, thermic, Grossarenic, Plinthitic Paleudult). Water use, marketable yield, and yield of U.S. #1 grade roots generally decreased when soil water tensions exceeded 25 kPa before irrigation, although soil water stress of 100 kPa during storage root development did not significantly affect yield. Regression equations are provided to describe the relationships of water use to plant age and to compute daily evapotranspiration: pan evaporation ratios (crop factors) for sweetpotatoes irrigated at 25, 50, and 100 kPa of soil water tension.

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BROMATOLOGIA DE GRAMÍNEAS TROPICAIS SOB DIFERENTES TENSÕES DE ÁGUA NO SOLO EM AMBIENTE PROTEGIDO

Nativa ◽

10.31413/nativa.v6i4.5588 ◽

2018 ◽

Vol 6 (4) ◽

pp. 415

Author(s):

Morgana Scaramussa Gonçalves ◽

Wilian Rodrigues Ribeiro ◽

Edvaldo Fialho Dos Reis ◽

Antônio Carlos Cóser

Keyword(s):

Soil Water ◽

Crude Protein ◽

Nutritive Value ◽

Production Systems ◽

Pasture Production ◽

Tropical Grasses ◽

Soil Water Tension ◽

Randomized Design ◽

Completely Randomized Design ◽

Water Tension

A irrigação é usada para conter os efeitos da sazonalidade de produção garantindo maior intensificação dos sistemas de produção a pasto, assim, contribuindo para o aumento da produção e do valor bromatológico das gramíneas. Dessa forma, objetivou-se com esse trabalho avaliar o valor bromatológico de gramíneas tropicais cultivadas em condições de ambiente protegido, submetidas a diferentes tensões de água no solo. Foram realizados três experimentos com as gramíneas Mombaça, Marandu e Tifton 85, onde cada qual, foi conduzida em um esquema de parcelas subdivididas, tendo nas parcelas os níveis do fator tensão de água no solo (20, 40, 50, 60 e 70 kPa) e nas subparcelas níveis 1º, 2º e 3º do fator corte, em um delineamento inteiramente casualizado com cinco repetições. Nas tensões de água no solo de 20 (Mombaça) e 50 kPa (Marandu e Tifton 85) as gramíneas expressaram seu máximo de valor nutritivo. Os maiores teores de PB foram obtidos nas gramíneas Mombaça e Tifton 85. Para as variáveis FDN e FDA o fator tensão de água no solo não foi significativo.Palavras-chave: proteína bruta, fibra, irrigação, forrageiras. BROMATOLOGY OF TROPICAL GRASSES UNDER DIFFERENT SOIL WATER TENSIONS IN PROTECTED ENVIRONMENT ABSTRACT:The irrigation is used to contain the effects of seasonality of production, ensuring a greater intensification of pasture production systems, thus contributing to the increase of production and the bromatological value of grasses. Thus, the objective of this work was to evaluate the nutritive value of tropical grasses grown under protected environment conditions, subject to different soil water stresses. Three experiments, using Mombasa, Marandu and Tifton 85 grasses under a protected environment were carried out and each one was conducted in a subdivided plots scheme, with the levels of soil water tension factor (20, 40, 50, 60 and 70 kPa) and in the subplots levels 1, 2 and 3 of the cut factor, in a completely randomized design with five replicationss. At soil water stresses of 20 (Mombasa) and 50 kPa (Marandu and Tifton 85) the grasses expressed their maximum nutritive value. The highest CP levels were obtained in the Mombasa and Tifton 85 grasses. For the NDF and ADF variables, the soil water stress factor was not significant.Keywords: crude protein, fiber, irrigation, forages.

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Rooting Depth, Growth and Yield of Sorghum as Affected by Soil Water Availability in an Ultisol and an Oxisol

The Journal of Agriculture of the University of Puerto Rico ◽

10.46429/jaupr.v60i3.10525 ◽

1969 ◽

Vol 60 ◽

pp. 329-335

Author(s):

A. Wahab ◽

H. Talleyrand ◽

M. A. Lugo-López

Keyword(s):

Soil Moisture ◽

Plant Growth ◽

Soil Water ◽

Grain Filling ◽

Growth And Yield ◽

Rooting Depth ◽

Weather Factors ◽

Soil Water Tension ◽

Available Soil Moisture ◽

Water Tension

Grain and stover yields of RS 671 grain sorghum were measured at Barranquitas in an Oxisol and at Corozal in an Ultisol. Measurements were made of weather factors, soil moisture content and tension, plant growth, water deficits and rooting depths. At each site a plot was irrigated as often as necessary to maintain a soil water tension of less than 1 bar. Nonirrigated plots at Corozal were watered whenever necessary to prevent plants from wilting permanently. During a prolonged drought and at grain filling, sorghum extracted water in the Oxisol to a depth of 120 cm. Plants became water stressed after the soil water tension at a depth of 90 cm reached 15 bars. In the Ultisol, sorghum plants were unable to effectively extract available soil moisture at depths below 45 cm. Both plant growth and grain yield were greater in the Oxisol than in the Ultisol. The relative soil compaction of the Ultisol was greater than that of the Oxisol.

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