Hydrometer Method Improved for Making Particle Size Analyses of Soils<sup>1</sup>

Bouyoucos, George John

doi:10.2134/agronj1962.00021962005400050028x

Cited by 4,183 publications

(1,928 citation statements)

References 2 publications

Supporting

Mentioning

1,799

Contrasting

Unclassified

120

Order By: Relevance

“…Density, total porosity, microporosity, and macroporosity were determined from the same undisturbed sample. Total clay was obtained after agitation and dispersion in 1 mol L -1 Na OH and natural clay after dispersion in water, by the densimeter method (Bouyoucos, 1962). After determining the granulometric fractions, the degree of flocculation was calculated.…”

Section: Methodsmentioning

confidence: 99%

Physical properties of a humic cambisol under tillage and cropping systems after twelve years

Andrade

Mafra

Baldo

et al. 2010

Rev. Bras. Ciênc. Solo

View full text Add to dashboard Cite

Soil is the basis underlying the food production chain and it is fundamental to improve and conserve its productive capacity. Imbalanced exploitation can degrade agricultural areas physical, chemical and biologically. The objective of this study was to evaluate some soil physical properties and their relation with organic carbon contents of a Humic Dystrudept under conventional tillage (CT) and no-tillage (NT), for 12 years in rotation (r) and succession (s) cropping systems. The experiment was carried out in Lages, SC (latitude 27 ° 49 ' S and longitude 50 ° 20 ' W, 937 m asl), using crop sequences of bean-fallow-maize-fallow-soybean in conventional tillage rotation; maize-fallow in conventional tillage succession; bean-oat-maize-turnip-soybean-vetch in no-tillage rotation; and maize-vetch in notillage succession. The experimental design was completely randomized with four replications. The soil samples were collected in the layers 0-2.5, 2.5-5, 5-10, and 10-20 cm. The following properties were analyzed: soil density, porosity, aggregate stability, degree of flocculation, water retention, infiltration, mechanical strength, and total organic carbon. Soil aggregation in the surface layer (0-5 cm) was better in the no-tillage than the conventional system, related to higher microporosity, organic carbon contents and water retention capacity, indicating that a periodical tillage of this soil is unnecessary. Infiltration was highest in no-tillage with crop succession.Index terms: crop rotation, crop succession, no-tillage, soil management.(

show abstract

Section: Methodsmentioning

confidence: 99%

Physical properties of a humic cambisol under tillage and cropping systems after twelve years

Andrade

Mafra

Baldo

et al. 2010

Rev. Bras. Ciênc. Solo

View full text Add to dashboard Cite

show abstract

“…The hydrometric method was used to determine the soil texture (Bouyoucos 1962). The soil texture was clay loam between 0 and 50 cm depth with a high percentage of calcium carbonate and a low value of the organic carbon.…”

Section: Field Experimentsmentioning

confidence: 99%

Modeling the effects of saline water use in wheat-cultivated lands using the UNSATCHEM model

2012

View full text Add to dashboard Cite

Waters of poor quality are often used to irrigate crops in arid and semiarid regions, including the Fars Province of southwest Iran. The UNSATCHEM model was first calibrated and validated using field data that were collected to evaluate the use of saline water for the wheat crop. The calibrated and validated model was then employed to study different aspects of the salinization process and the impact of rainfall. The effects of irrigation water quality on the salinization process were evaluated using model simulations, in which irrigation waters of different salinity were used. The salinization process under different practices of conjunctive water use was also studied using simulations. Different practices were evaluated and ranked on the basis of temporal changes in rootzone salinity, which were compared with respect to the sensitivity of wheat to salinity. This ranking was then verified using published field studies evaluating wheat yield data for different practices of conjunctive water use. Next, the effects of the water application rate on the soil salt balance were studied using the UNSATCHEM simulations. The salt balance was affected by the quantity of applied irrigation water and precipitation/dissolution reactions. The results suggested that the less irrigation water is used, the more salts (calcite and gypsum) precipitate from the soil solution. Finally, the model was used to evaluate how the electrical conductivity of irrigation water affects the wheat production while taking into account annual rainfall and its distribution throughout the year. The maximum salinity of the irrigation water supply, which can be safely used in the long term (33 years) without impairing the wheat production, was determined to be 6 dS m -1 . Rainfall distribution also plays a major role in determining seasonal soil salinity of the root zone. Winter-concentrated rainfall is more effective in reducing salinity than a similar amount of rainfall distributed throughout autumn, winter, and spring seasons.

show abstract

“…Standard procedures were used in determining bulk densíty by the core method, hydraulic conductivity in water saturated samples, and water retention at 1/3 and 15 bar tension (19). Partic1e-size distribution (fraetions 2-0.2 mm, 0.2-0.02 mm, 0.02-0.002 mm, < 0.002 mm) were determined by the hydrometer method (5).…”

Section: Materlals and Methodsmentioning

confidence: 99%

Characterization and Evaluation of Agricultural Benchmark Soils from Sevilla, Spain

Rosa¹,

Mudarra²,

Romero³

et al. 1984

Soil Science Soc of Amer J

View full text Add to dashboard Cite

In Sevilla Province, s6utbwestern Spain, bencbmark soils of eigbt agricultural areas were defined using traditional soil ped6n c6ncepts of S6i1 survey. The characterizati6n emphasized morpb6logical, chemical, and physical analyses. These eigbt representative S6i1S were cIassified as f6116WS: R6jO Aljarafe (Typic Rbod6xeralO, Tierraneara Camp6 (Typic PeIl6xerert), Salin6 Marismas (Vertic Fluvaquent), Franc6 Vega (Typic Xerofluvent), Arena Terrazas (Aquic HaploxeralO, Almagra Alc6res (Calcic Hapl6xeralO, Bujeo Campiña (Typic Chr6m6xerert), and Albariza Estepa (Entic Hapl6xer-611). By application of a computer-based soil evaluation system developed with inf6rmati6n from a representative zone, predlcted yIelds were calculated f6r wheat (Triticum IIntirum L.), field coro (Zu lIUIys L.), and coUon (Gossypium IIinutum L.) for tbe selected bencbmark soils. Productivity inf6rmation was transferred from the representative mne t6 tbe eight agricultural areas within Sevilla Provinee. Soils were ranked in tbe f6I16wing 6rder acoording t6 predicted yields f6r the tbree crops: Bujeo Campiña > Tierranegra Campo > Franco Vega> Salin6 Marismas> R6jO Aljarafe> Almagra AIcores > Albariza Estepa > Arena Terrazas.

show abstract

Hydrometer Method Improved for Making Particle Size Analyses of Soils¹

Cited by 4,183 publications

References 2 publications

Physical properties of a humic cambisol under tillage and cropping systems after twelve years

Physical properties of a humic cambisol under tillage and cropping systems after twelve years

Modeling the effects of saline water use in wheat-cultivated lands using the UNSATCHEM model

Characterization and Evaluation of Agricultural Benchmark Soils from Sevilla, Spain

Contact Info

Product

Resources

About

Hydrometer Method Improved for Making Particle Size Analyses of Soils1

Cited by 4,183 publications

References 2 publications

Physical properties of a humic cambisol under tillage and cropping systems after twelve years

Physical properties of a humic cambisol under tillage and cropping systems after twelve years

Modeling the effects of saline water use in wheat-cultivated lands using the UNSATCHEM model

Characterization and Evaluation of Agricultural Benchmark Soils from Sevilla, Spain

Contact Info

Product

Resources

About

Hydrometer Method Improved for Making Particle Size Analyses of Soils¹