143:. An example of a soil triangle is found on the right side of the page. One side of the triangle represents percent sand, the second side represents percent clay, and the third side represents percent silt. If the percentages of sand, clay, and silt in the soil sample are known, then the triangle can be used to determine the soil texture classification. For example, if a soil is 70 percent sand and 10 percent clay then the soil is classified as a sandy loam. The same method can be used starting on any side of the soil triangle. If the texture by feel method was used to determine the soil type, the triangle can also provide a rough estimate on the percentages of sand, silt, and clay in the soil.
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interactions and are small enough to ensure that the fluid flow stays laminar. Deviations from Stokes' equation are to be expected in case of irregularly shaped particles, such as clay particles which are mostly platy or tubular. The stable position during settling of particles with such shapes is with the maximum cross-sectional area being perpendicular to the direction of motion. For this reason, the drag resistance of particles increases and the settling velocity decreases. The particle diameter is directly proportional to the settling velocity. Therefore, with lower velocity, the calculated diameter also decreases determining an overestimation of the fine size fraction.
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its own weight. Measuring the length of the ribbon can help determine the amount of clay in the sample. After making a ribbon, excessively wet a small pinch of soil in the palm of the hand and rub in with the forefinger to determine the amount of sand in the sample. Soils that have a high percentage of sand, such as sandy loam or sandy clay, have a gritty texture. Soils that have a high percentage of silt, such as silty loam or silty clay, feel smooth. Soils that have a high percentage of clay, such as clay loam, have a sticky feel. Although the texture by feel method takes practice, it is a useful way to determine soil texture, especially in the field.
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between six and twenty-four hours (depending on the protocol used) to measure clay. The number on the hydrometer that is visible (above the soil solution) is recorded. A blank (containing only water and the dispersing agent) is used to calibrate the hydrometer. The values recorded from the readings are used to calculate the percent clay, silt and sand. The blank is subtracted from each of the three readings. The calculations are as follows:
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is determined in relation to their potential volume, which is calculated on the basis of an optical diffraction image at the edges of the particle cross-section. The volume of clay particles is the diameter of the plate’s cross-section, which is treated in the calculations as the diameter of the sphere. Therefore, their dimensions are usually overestimated in comparison to those measured via sedimentation analysis.
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within and between fields as well as identifying progressive changes and boundaries between soil map units (soil series). Texture by feel is a qualitative method, as it does not provide exact values of sand, silt, and clay. Although qualitative, the texture by feel flowchart can be an accurate way for a scientist or interested individual to analyze the relative proportions of sand, silt, and clay.
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challenging because of the high cohesiveness of particles, stickiness of powder to the sieve, and electrostatic charges. Moreover, in the sieving particles pass with the smallest side through the mesh opening, which means that the plate-shaped clay and silt particles might be sieved as well. In all this generally leads to a massive underestimation of the fine fraction.
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samples can be measured without external sample preparation steps, which are required for sieving and sedimentation analysis. Moreover, since the sample can be dispersed properly, there is no need to combine two different measurement techniques to obtain the full range of the particle size distribution, including the silt and clay content.
470:. The optical properties of anisotropic particles, such as refractive index and absorption index, change according to their orientation relative to the laser beam which is also variable. Therefore, at different particles orientations different cross-sections will be measured and different diffraction patterns produced.
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Chemical and physical properties of a soil are related to texture. Particle size and distribution will affect a soil's capacity for holding water and nutrients. Fine textured soils generally have a higher capacity for water retention, whereas sandy soils contain large pore spaces that allow leaching.
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Both
Fraunhofer and Mie laser diffraction theories assume that particles are spherically shaped. This results in a small measurement error, since small particles in soil samples, such as clay and silt in particular, are elongated and anisotropic. The particle diameter in the laser diffraction method
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In order to measure silt and clay (with a particle size below 60 μm), a second, independent sizing method (most often hydrometer or pipette technique) is used on the sample taken from the bottom sieve. Particle size distribution obtained from sieve analysis should be combined with the data from
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The Stokes' diameter determined via sedimentation method is the diameter of a sphere having the same settling velocity and same density as the particle. This is the reason why the sedimentation analysis applies well when assuming that particles are spherical, have similar densities, have negligible
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A soil hydrometer measures the relative density of liquids (density of a liquid compared to the density of water). The hydrometer is lowered into the cylinder containing the soil mixture at different times, forty-five seconds to measure sand content, one and a half hours to measure silt content and
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within 24 hours was most rapid in this fraction, and the pores between compacted particles were so small as to prevent the entry of root hairs. Commission One of the
International Society of Soil Science (ISSS) recommended its use at the first International Congress of Soil Science in Washington in
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The texture by feel method involves taking a small sample of soil and making a ribbon. A ribbon can be made by taking a ball of soil and pushing the soil between the thumb and forefinger and squeezing it upward into a ribbon. Allow the ribbon to emerge and extend over the forefinger, breaking from
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Compared to other techniques laser diffraction is a fast and cost-effective method to measure particle size and quickly analyze soil samples. A big advantage is the built-in dispersion (e.g. dispersion by air pressure or ultrasound dispersion) unit of laser diffraction instruments. Therefore, dry
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overnight. The solution is transferred to one liter graduated cylinders and filled with water. The soil solution is mixed with a metal plunger to disperse the soil particles. The soil particles separate based on size and sink to the bottom. Sand particles sink to the bottom of the cylinder first.
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Hand analysis is a simple and effective means to rapidly assess and classify a soil's physical condition. Correctly executed, the procedure allows for rapid and frequent assessment of soil characteristics with little or no equipment. It is thus a useful tool for identifying spatial variation both
132:. Soil textures are classified by the fractions of each soil separate (sand, silt, and clay) present in a soil. Classifications are typically named for the primary constituent particle size or a combination of the most abundant particles sizes, e.g. "sandy clay" or "silty clay". A fourth term,
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The method is used to determine the grain size distribution of soils that are greater than 75 μm in diameter, as sieving has a strong disadvantage in the lower measurement border. In fact, in case of finer fraction at high content of clay and silt (below 60 μm), the dispersion becomes
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Sedimentation analysis shows anyways limits for particles smaller than 0.2 micron because such small particles undergo
Brownian motion in the suspension and do not settle anymore as per the Stokes' law. Sedimentation analysis can be operated continuously with a high degree of accuracy and
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According to this law the particles settle down because of the weight and gravity action. However, there are two additional forces acting in the opposite direction of particles's motion which determines the equilibrium condition at which the particle falls at a constant velocity called
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repeatability. The particle size distribution of soil containing a significant number of finer particles (silt and clay) cannot be performed by sieve analysis solely, therefore sedimentation analysis is used to determine the lower range of the particle size distribution.
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Sieving is a long-established but still widely used soil analysis technique. In sieving, a known weight of sample material passes through finer sieves. The amount collected on each sieve is weighted to determine the percentage weight in each size fraction.
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in 1905 and was based on his studies in southern Sweden. Atterberg chose 20 μm for the upper limit of silt fraction because particles smaller than that size were not visible to the naked eye, the suspension could be coagulated by salts,
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is a measurement technique for determining the particle size distribution of samples, either dispersed in a liquid or as a dry powder. The technique is based on light waves getting bent when encountering particles in a sample. The measured
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The angle of diffraction depends on the particle size, hence the pattern of diffraction depends on the relative amounts of different particle sizes present in that sample. This diffraction pattern is then detected and analyzed by means of
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Prescott JA, Taylor JK, Marshall TJ (1934) "The relationship between the mechanical composition of the soil and the estimate of texture in the field." Transactions of the First
Commission of the International Society of Soil Science 1,
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By means of laser diffraction not only the particle size distribution and the corresponding volume weighted D-values can be determined but also the percentage of particles in the main size classes used for the soil classification.
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There are several additional quantitative methods to determine soil texture. Some examples of these methods are the pipette method, the x-ray sedimentation, the particulate organic matter (POM) method, the rapid method.
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particles and are classified as having diameters of less than 0.002 mm. Clay particles are plate-shaped instead of spherical, allowing for an increased specific surface area. The next smallest particles are
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of the particles’ material, including their absorption coefficient. Because these parameters are often difficult to retrieve, especially the light absorption coefficients for various particles and soil grains,
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Sedimentation analysis (e.g. pipette method, hydrometer) is commonly used in the soil industry or in geology to classify sediments.The hydrometer method was developed in 1927 and is still widely used today.
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The x-ray sedimentation technique is a hybrid technique which combines sedimentation and x-ray absorption. The particle size is calculated from the terminal settling velocities of particles by applying
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classes based on their physical texture. Soil texture can be determined using qualitative methods such as texture by feel, and quantitative methods such as the hydrometer method based on
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In the United States, twelve major soil texture classifications are defined by the United States
Department of Agriculture. The twelve classifications are sand, loamy sand, sandy loam,
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Marshall TJ (1947) "Mechanical composition of soil in relation to field descriptions of texture." Council for
Scientific and Industrial Research, Bulletin No. 224, Melbourne.
34:. Soil texture has agricultural applications such as determining crop suitability and to predict the response of the soil to environmental and management conditions such as
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Kettler, T., Doran, J., Gilbert, T., 2001. Simplified method for soil particle-size determination to accompany soil-quality analyses. Soil Sci. Soc. Am. J. 65:849–853
136:, is used to describe equal properties of sand, silt, and clay in a soil sample, and lends to the naming of even more classifications, e.g. "clay loam" or "silt loam".
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Soil
Science Division Staff. 2017. Soil survey sand. C. Ditzler, K. Scheffe, and H.C. Monger (eds.). USDA Handbook 18. Government Printing Office, Washington, D.C.
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Natural
Resources Conservation Service. (n.d.). Retrieved November 29, 2017, from https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/edu/?cid=nrcs142p2_054311
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Davis ROE, Bennett HH (1927) "Grouping of soils on the basis of mechanical analysis." United States
Department of Agriculture Departmental Circulation No. 419.
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The hydrometer method of determining soil texture is a quantitative measurement providing estimates of the percent sand, clay, and silt in the soil based on
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Bouyoucos, George. 1936. Directions for making mechanical analysis of soils by the hydrometer method. Soil
Science. Vol 42 Issue 3: pp 225–230
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Whitney M (1911) "The use of soils east of the Great Plains region." United States Department of Agriculture Bureau of Soils Bulletin No. 78.
486:, which only takes into account the light diffraction phenomena at the edge of the particles, is often recommended for natural soils.
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389:, which acts as a dispersing agent to separate soil aggregates. The soil is mixed with the sodium hexametaphosphate solution on an
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Bouyoucos G. 1951. A recalibration of the hydrometer method for making mechanical analysis of soils. American Society of Agronomy.
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508:. The adsorption of the x-radiation is used to determine the relative mass concentration for each size class by applying the
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is the diameter of a sphere having on the cross-sectional area the same diffraction pattern as the investigated particle.
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1927. Australia adopted this system, and its equal logarithmic intervals are an attractive feature worth maintaining. The
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particles and have diameters between 0.002 mm and 0.05 mm (in USDA soil taxonomy). The largest particles are
42:(lime) requirements. Soil texture focuses on the particles that are less than two millimeters in diameter which include
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Silt particles sink to the bottom of the cylinder after the sand. Clay particles separate out above the silt layer.
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955:"Particle Size Distribution of Natural Clayey Soils: A Discussion on the Use of Laser Diffraction Analysis (LDA)"
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particles and are larger than 0.05 mm in diameter. Furthermore, large sand particles can be described as
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Toogood JA (1958) "A simplified textural classification diagram." Canadian Journal of Soil Science 38, 54–55.
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The error associated with the assumption of the sphericity of particles depends furthermore on the degree of
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Soil texture triangle, showing the 12 major textural classes, and particle size scales as defined by the USDA
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1004:"Methodological aspects of determining soil particle-size distribution using the laser diffraction method"
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Percent silt = (dried mass of soil – sand hydrometer reading – blank reading) / (dried mass of soil) *100
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Atterberg A (1905) Die rationalle Klassifikation der Sande und Kiese. Chemiker Zeitung 29, 195–198.
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Soil Texture, by R. B. Brown, University of Florida, Institute of Food and Agricultural Sciences.
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804:"Comparing Particle Size Distribution Analysis by Sedimentation and Laser Diffraction Method"
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a sedimentation analysis to establish a complete particle size distribution of the sample.
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325:(WRB) uses an alternative method to determine texture by feel, offering another flow chart.
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Percent clay = (clay hydrometer reading – blank reading) / (dried mass of soil) *100
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Soil separates are specific ranges of particle sizes. The smallest particles are
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Flow Chart to determine soil texture as used by the 4th edition of the WRB
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Particle size classifications used by different countries, diameters in μm
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The first classification, the International system, was first proposed by
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Particulate products : tailoring properties for optimal performance
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Determining soil texture is often aided with the use of a soil texture
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system uses 11. These classifications are based on the percentages of
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soil classification systems use 12 textural classes whereas the
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900:"Laser diffraction for particle sizing :: Anton Paar Wiki"
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For clays with sizes close to the wavelength of a laser beam,
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instrument used both in the field and laboratory to determine
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would be desirable. This requires precise knowledge of the
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714:"Standard Test Method for Particle-Size Analysis of Soils"
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Gorączko, Aleksandra; Topoliński, Szymon (2020-01-31).
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Ryżak, Magdalena; Bieganowski, Andrzej (August 2011).
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411:Percent sand = 100 – (percent clay + percent silt)
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2197:Australian Society of Soil Science Incorporated
762:Henk G. Merkus; Gabriel M. H. Meesters (2014).
693:"Determining Soil Texture by the "Feel Method""
637:. Soil Science Society of America. p. 17.
100:(USDA) adopted its own system in 1938, and the
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802:Ferro, Vito; Mirabile, Stefano (2009-06-30).
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385:The hydrometer method requires the use of
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666:. Canada: John Wiley & Sons. p.
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662:Fundamentals of Soil Science 8th Edition
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108:world soil map and recommended its use.
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387:sodium hexametaphosphate
2419:List of soil scientists
1761:1938 USDA soil taxonomy
1740:Référentiel pédologique
1724:FAO soil classification
658:Foth, Henry D. (1990).
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861:Ranjan, Gopal (2007).
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197:Diameter limits (mm)
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971:2020Geosc..10...55G
499:X-ray sedimentation
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1471:for Soil Resources
1358:Pore space in soil
1301:Soil acidification
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768:. Cham: Springer.
614:on 19 January 2022
607:Soil survey manual
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775:978-3-319-00714-4
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1053:
1052:
1047:
1043:
1000:
996:
951:
942:
933:
931:
922:
921:
917:
908:
906:
898:
897:
890:
875:
859:
855:
800:
791:
776:
760:
756:
751:
740:
735:
731:
722:
720:
712:
711:
707:
695:
691:Thien, Steven.
689:
685:
678:
656:
652:
645:
631:
627:
617:
615:
602:
595:
590:
586:
581:
577:
572:
568:
561:
550:
545:
518:
501:
492:
425:
364:
339:
303:
301:Texture by feel
298:
220:less than 0.002
207:
203:classification)
198:
153:
114:
84:
17:
12:
11:
5:
2468:
2458:
2457:
2452:
2447:
2442:
2425:
2424:
2422:
2421:
2411:
2405:
2394:
2383:
2380:
2379:
2377:
2376:
2371:
2369:Surface runoff
2362:
2357:
2352:
2347:
2342:
2337:
2332:
2326:
2324:
2320:
2319:
2317:
2316:
2309:
2302:
2295:
2292:Plant and Soil
2288:
2281:
2273:
2271:
2267:
2266:
2264:
2263:
2258:
2253:
2247:
2242:
2236:
2230:
2225:
2220:
2215:
2210:
2204:
2199:
2193:
2191:
2187:
2186:
2184:
2183:
2182:
2181:
2171:
2166:
2161:
2156:
2151:
2146:
2141:
2136:
2131:
2126:
2120:
2118:
2117:Related fields
2114:
2113:
2111:
2110:
2105:
2100:
2095:
2090:
2085:
2080:
2075:
2070:
2065:
2060:
2054:
2052:
2048:
2047:
2042:
2041:
2031:
2028:
2027:
2025:
2024:
2019:
2014:
2009:
2004:
1999:
1994:
1989:
1984:
1979:
1974:
1972:Prime farmland
1969:
1964:
1959:
1954:
1949:
1944:
1939:
1934:
1929:
1927:Fuller's earth
1924:
1919:
1917:Expansive clay
1914:
1909:
1904:
1899:
1894:
1889:
1884:
1879:
1874:
1869:
1864:
1859:
1854:
1849:
1844:
1839:
1834:
1829:
1824:
1819:
1814:
1809:
1804:
1799:
1794:
1789:
1783:
1781:
1777:
1776:
1774:
1773:
1768:
1763:
1758:
1753:
1748:
1743:
1737:
1732:
1727:
1720:
1718:
1714:
1713:
1711:
1710:
1705:
1700:
1695:
1690:
1685:
1680:
1675:
1670:
1665:
1660:
1655:
1649:
1647:
1641:
1640:
1638:
1637:
1632:
1627:
1622:
1617:
1612:
1607:
1602:
1597:
1592:
1587:
1582:
1577:
1572:
1567:
1562:
1557:
1552:
1547:
1542:
1537:
1532:
1527:
1522:
1517:
1512:
1507:
1502:
1497:
1492:
1487:
1482:
1476:
1474:
1465:
1464:
1457:
1456:
1449:
1442:
1434:
1428:
1426:
1420:
1419:
1417:
1416:
1415:
1414:
1404:
1399:
1398:
1397:
1387:
1382:
1380:Soil biomantle
1377:
1372:
1367:
1366:
1365:
1360:
1353:Soil structure
1350:
1345:
1340:
1335:
1333:Soil fertility
1330:
1325:
1320:
1315:
1310:
1305:
1304:
1303:
1293:
1292:
1291:
1281:
1276:
1275:
1274:
1264:
1259:
1254:
1249:
1248:
1247:
1245:Soil formation
1242:
1237:
1227:
1221:
1219:
1215:
1214:
1207:
1205:
1203:
1202:
1197:
1192:
1190:Soil chemistry
1187:
1185:Soil mechanics
1182:
1177:
1172:
1167:
1162:
1157:
1152:
1146:
1144:
1140:
1139:
1137:
1136:
1131:
1125:
1122:
1121:
1114:
1113:
1106:
1099:
1091:
1085:
1084:
1081:
1078:
1075:
1066:
1062:
1057:
1054:
1051:
1050:
1041:
1014:(4): 624–633.
994:
940:
915:
888:
873:
853:
789:
774:
754:
738:
729:
705:
683:
676:
650:
643:
625:
593:
584:
575:
566:
547:
546:
544:
541:
540:
539:
534:
529:
524:
517:
514:
500:
497:
491:
488:
424:
421:
391:orbital shaker
363:
360:
338:
335:
302:
299:
297:
294:
291:
290:
287:
284:
280:
279:
276:
273:
269:
268:
265:
262:
258:
257:
254:
251:
247:
246:
245:0.063 – 0.125
243:
240:
239:Very fine sand
236:
235:
234:0.002 – 0.063
232:
229:
225:
224:
221:
218:
214:
213:
204:
195:
152:
151:Soil separates
149:
113:
112:Classification
110:
93:capillary rise
83:
80:
24:classification
15:
9:
6:
4:
3:
2:
2467:
2456:
2453:
2451:
2448:
2446:
2443:
2441:
2438:
2437:
2435:
2420:
2412:
2410:
2406:
2404:
2403:Category soil
2395:
2393:
2385:
2384:
2381:
2375:
2372:
2370:
2366:
2363:
2361:
2358:
2356:
2353:
2351:
2348:
2346:
2343:
2341:
2338:
2336:
2333:
2331:
2328:
2327:
2325:
2321:
2315:
2314:
2310:
2308:
2307:
2306:Soil Research
2303:
2301:
2300:
2299:Pochvovedenie
2296:
2294:
2293:
2289:
2287:
2286:
2282:
2280:
2279:
2275:
2274:
2272:
2268:
2262:
2259:
2257:
2254:
2251:
2248:
2246:
2243:
2240:
2237:
2234:
2231:
2229:
2226:
2224:
2221:
2219:
2216:
2214:
2211:
2208:
2205:
2203:
2200:
2198:
2195:
2194:
2192:
2188:
2180:
2177:
2176:
2175:
2172:
2170:
2167:
2165:
2162:
2160:
2157:
2155:
2152:
2150:
2147:
2145:
2142:
2140:
2139:Geomorphology
2137:
2135:
2132:
2130:
2127:
2125:
2122:
2121:
2119:
2115:
2109:
2108:Liming (soil)
2106:
2104:
2101:
2099:
2096:
2094:
2091:
2089:
2086:
2084:
2081:
2079:
2076:
2074:
2071:
2069:
2066:
2064:
2061:
2059:
2056:
2055:
2053:
2049:
2039:
2038:Types of soil
2029:
2023:
2020:
2018:
2017:Tropical peat
2015:
2013:
2010:
2008:
2005:
2003:
2000:
1998:
1995:
1993:
1990:
1988:
1985:
1983:
1980:
1978:
1975:
1973:
1970:
1968:
1965:
1963:
1960:
1958:
1955:
1953:
1950:
1948:
1945:
1943:
1940:
1938:
1935:
1933:
1930:
1928:
1925:
1923:
1920:
1918:
1915:
1913:
1910:
1908:
1905:
1903:
1902:Dry quicksand
1900:
1898:
1895:
1893:
1890:
1888:
1885:
1883:
1880:
1878:
1875:
1873:
1870:
1868:
1865:
1863:
1860:
1858:
1855:
1853:
1850:
1848:
1845:
1843:
1840:
1838:
1835:
1833:
1830:
1828:
1825:
1823:
1820:
1818:
1815:
1813:
1810:
1808:
1805:
1803:
1800:
1798:
1795:
1793:
1790:
1788:
1785:
1784:
1782:
1778:
1772:
1769:
1767:
1764:
1762:
1759:
1757:
1754:
1752:
1749:
1747:
1744:
1741:
1738:
1736:
1733:
1731:
1728:
1725:
1722:
1721:
1719:
1717:Other systems
1715:
1709:
1706:
1704:
1701:
1699:
1696:
1694:
1691:
1689:
1686:
1684:
1681:
1679:
1676:
1674:
1671:
1669:
1666:
1664:
1661:
1659:
1656:
1654:
1651:
1650:
1648:
1646:
1642:
1636:
1633:
1631:
1628:
1626:
1623:
1621:
1618:
1616:
1613:
1611:
1608:
1606:
1603:
1601:
1598:
1596:
1593:
1591:
1588:
1586:
1583:
1581:
1578:
1576:
1573:
1571:
1568:
1566:
1563:
1561:
1558:
1556:
1553:
1551:
1548:
1546:
1543:
1541:
1538:
1536:
1533:
1531:
1528:
1526:
1523:
1521:
1518:
1516:
1513:
1511:
1508:
1506:
1503:
1501:
1498:
1496:
1493:
1491:
1488:
1486:
1483:
1481:
1478:
1477:
1475:
1472:
1466:
1462:
1455:
1450:
1448:
1443:
1441:
1436:
1435:
1432:
1427:
1425:
1421:
1413:
1410:
1409:
1408:
1407:Soil moisture
1405:
1403:
1400:
1396:
1393:
1392:
1391:
1388:
1386:
1383:
1381:
1378:
1376:
1373:
1371:
1368:
1364:
1361:
1359:
1356:
1355:
1354:
1351:
1349:
1346:
1344:
1341:
1339:
1336:
1334:
1331:
1329:
1326:
1324:
1321:
1319:
1316:
1314:
1311:
1309:
1306:
1302:
1299:
1298:
1297:
1294:
1290:
1287:
1286:
1285:
1284:Soil salinity
1282:
1280:
1277:
1273:
1270:
1269:
1268:
1265:
1263:
1260:
1258:
1255:
1253:
1250:
1246:
1243:
1241:
1240:Pedodiversity
1238:
1236:
1233:
1232:
1231:
1228:
1226:
1223:
1222:
1220:
1216:
1211:
1201:
1198:
1196:
1193:
1191:
1188:
1186:
1183:
1181:
1178:
1176:
1173:
1171:
1168:
1166:
1163:
1161:
1158:
1156:
1153:
1151:
1148:
1147:
1145:
1141:
1135:
1132:
1130:
1127:
1126:
1123:
1119:
1112:
1107:
1105:
1100:
1098:
1093:
1092:
1089:
1082:
1079:
1076:
1074:
1071:
1067:
1063:
1060:
1059:
1045:
1037:
1033:
1029:
1025:
1021:
1017:
1013:
1009:
1005:
998:
990:
986:
981:
976:
972:
968:
964:
960:
956:
949:
947:
945:
929:
925:
919:
905:
901:
895:
893:
884:
880:
876:
870:
866:
865:
857:
849:
845:
841:
837:
832:
827:
822:
817:
813:
809:
805:
798:
796:
794:
785:
781:
777:
771:
767:
766:
758:
749:
747:
745:
743:
733:
719:
715:
709:
701:
694:
687:
679:
677:0-471-52279-1
673:
669:
664:
663:
654:
646:
644:9780891189541
640:
636:
629:
613:
609:
608:
600:
598:
588:
579:
570:
564:
559:
557:
555:
553:
548:
538:
535:
533:
530:
528:
525:
523:
520:
519:
513:
511:
507:
496:
487:
485:
480:
476:
471:
469:
464:
460:
456:
452:
450:
446:
442:
436:
434:
429:
420:
416:
412:
409:
406:
403:
400:
395:
392:
388:
383:
381:
375:
373:
368:
359:
355:
347:
343:
330:
326:
324:
319:
315:
307:
288:
285:
282:
281:
277:
274:
271:
270:
266:
263:
260:
259:
256:0.125 – 0.20
255:
252:
249:
248:
244:
241:
238:
237:
233:
230:
227:
226:
222:
219:
216:
215:
211:
205:
202:
196:
193:
192:
189:
187:
183:
179:
175:
171:
166:
157:
148:
144:
142:
141:triangle plot
137:
135:
131:
127:
118:
109:
107:
103:
99:
94:
89:
79:
78:in the soil.
77:
73:
69:
65:
61:
57:
53:
49:
45:
41:
37:
33:
29:
25:
21:
2450:Soil science
2311:
2304:
2297:
2290:
2283:
2276:
2159:Biogeography
2154:Hydrogeology
2129:Geochemistry
2051:Applications
1947:Martian soil
1375:Soil horizon
1348:Soil texture
1347:
1323:Soil quality
1279:Soil sealing
1252:Soil erosion
1180:Soil physics
1175:Soil ecology
1170:Soil zoology
1160:Soil biology
1118:Soil science
1069:
1044:
1011:
1007:
997:
962:
958:
932:. Retrieved
927:
918:
907:. Retrieved
903:
863:
856:
811:
807:
764:
757:
732:
721:. Retrieved
718:www.astm.org
717:
708:
700:NDHealth.gov
699:
686:
661:
653:
634:
628:
616:. Retrieved
612:the original
606:
587:
578:
569:
562:
502:
493:
472:
465:
461:
457:
453:
437:
426:
417:
413:
410:
407:
404:
396:
384:
376:
369:
365:
356:
352:
340:
320:
316:
312:
289:1.25 – 2.00
278:0.63 – 1.25
267:0.20 – 0.63
231:0.002 – 0.05
185:
181:
177:
173:
169:
164:
162:
145:
138:
123:
85:
20:Soil texture
19:
18:
2355:Groundwater
2169:Archaeology
2103:Agroecology
2073:Soil survey
2012:Terra rossa
2007:Terra preta
1987:Spodic soil
1907:Duplex soil
1887:Brown earth
1867:Alkali soil
1857:Rhizosphere
1852:Laimosphere
1726:(1974–1998)
1683:Inceptisols
1590:Plinthosols
1555:Kastanozems
1385:Soil carbon
1308:Soil health
1289:Alkali soil
1218:Soil topics
1143:Main fields
959:Geosciences
930:(in German)
831:10447/40752
506:Stokes' law
372:Stokes' law
296:Methodology
286:1.00 – 2.00
275:0.50 – 1.00
272:Coarse sand
264:0.25 – 0.50
261:Medium sand
253:0.10 – 0.25
242:0.05 – 0.10
32:Stokes' law
2434:Categories
2345:Vegetation
2088:Soil value
1992:Stagnogley
1942:Lunar soil
1897:Dark earth
1882:Brickearth
1847:Pedosphere
1817:Soil crust
1625:Technosols
1610:Solonchaks
1530:Ferralsols
1495:Anthrosols
1370:Soil crust
1343:Soil color
1328:Soil value
1230:Pedosphere
1155:Edaphology
934:2022-07-20
928:Anton Paar
909:2022-07-20
904:Anton Paar
723:2022-07-20
543:References
532:Hydrometer
522:Soil color
475:Mie theory
468:anisotropy
445:Fraunhofer
2374:Petrichor
2149:Hydrology
2134:Petrology
2078:Soil test
1977:Quicksand
1922:Fill dirt
1862:Bulk soil
1708:Vertisols
1698:Spodosols
1688:Mollisols
1678:Histosols
1663:Aridisols
1635:Vertisols
1630:Umbrisols
1620:Stagnosol
1585:Planosols
1580:Phaeozems
1560:Leptosols
1545:Gypsisols
1535:Fluvisols
1515:Chernozem
1510:Cambisols
1505:Calcisols
1500:Arenosols
1424:Soil type
1313:Soil life
1036:1436-8730
989:2076-3263
965:(2): 55.
883:171112208
840:2239-6268
814:(2): 35.
784:864591828
618:30 August
250:Fine sand
2440:Pedology
2330:Land use
2323:See also
2179:Agrology
1962:Paleosol
1877:Blue goo
1832:Gypcrust
1703:Ultisols
1673:Gelisols
1668:Entisols
1658:Andisols
1653:Alfisols
1615:Solonetz
1605:Retisols
1600:Regosols
1575:Nitisols
1570:Luvisols
1565:Lixisols
1550:Histosol
1540:Gleysols
1525:Durisols
1520:Cryosols
1490:Andosols
1480:Acrisols
1390:Soil gas
1150:Pedology
1065:143–153.
848:67844152
516:See also
2407:
2209:(India)
2124:Geology
1912:Eluvium
1872:Bay mud
1837:Caliche
1827:Hardpan
1822:Claypan
1812:Subsoil
1807:Topsoil
1693:Oxisols
1595:Podzols
1485:Alisols
1473:(1998–)
1296:Soil pH
1129:History
1016:Bibcode
967:Bibcode
451:(PSD).
337:Sieving
82:History
64:UK-ADAS
54:. The
40:calcium
36:drought
2396:
2022:Yedoma
1957:Muskeg
1034:
987:
881:
871:
867:. : .
846:
838:
782:
772:
674:
641:
182:medium
178:coarse
106:UNESCO
74:, and
50:, and
2002:Takir
1937:Loess
1134:Index
844:S2CID
696:(PDF)
22:is a
2252:(US)
2241:(UK)
2235:(US)
1967:Peat
1802:Loam
1797:Clay
1792:Silt
1787:Sand
1225:Soil
1032:ISSN
985:ISSN
879:OCLC
869:ISBN
836:ISSN
780:OCLC
770:ISBN
672:ISBN
639:ISBN
620:2014
443:and
228:Silt
217:Clay
201:USDA
186:fine
174:sand
170:silt
165:clay
134:loam
130:clay
126:loam
76:clay
72:silt
68:sand
58:and
52:clay
48:silt
44:sand
28:soil
1952:Mud
1024:doi
1012:174
975:doi
826:hdl
816:doi
441:Mie
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