مقایسه برخی روش‏های اندازه‏گیری توزیع اندازه ذرات اولیه خاک و ارائه زمان‏های مناسب برای روش چهار قرائت تعیین بافت خاک

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی کارشناسی ارشد، گروه علوم و مهندسی خاک، دانشکده مهندسی و فناوری، دانشگاه تهران، کرج، ایران

2 دانشیار گروه علوم و مهندسی خاک، دانشکده مهندسی و فناوری، دانشگاه تهران، کرج، ایران

3 دانشیارپژوهش موسسه تحقیقات خاک و آب، ﺳﺎزﻣﺎن ﺗﺤﻘﯿﻘﺎت، آﻣﻮزش و ﺗﺮوﯾﺞ ﮐﺸﺎورزی، ﮐﺮج، اﯾﺮان

چکیده

برای تعیین توزیع اندازه ذرات اولیه (PSD) در آزمایشگاه‏های خاکشناسی ایران، از روش‏های مختلفی استفاده می‏شود که این امر در بسیاری از شرایط امکان مقایسه نتایج و نیز دقت آنها را دشوار می­کند. پژوهش حاضر برای رسیدن به یک راهکار مشخص که در عین سادگی و ارزان بودن، دقت قابل قبولی نیز داشته باشد، انجام شد. ابتدا با توجه به برخی ویژگی‏های خاک از جمله درصد مواد سیمان‏کننده، 112 نمونه خاک از 16 استان مختلف کشور از کاربری‏ها و اقلیم‏های مختلف تهیه شد. PSD خاک با روش هیدرومتر با و بدون حذف مواد سیمان‏کننده اندازه‏گیری شد. نتایج نشان داد، روش رایج قرائت40 ثانیه و 2 ساعت (Bouyoucos, 1962)، بخش رس را با میانگین خطای مطلق (g/g100) 5/9 درصد نسبت به روش قرائت کامل اندازه­گیری می­کند و در 5/40 درصد از خاک­های مورد بررسی بیش از 10 درصد و در 2/94 درصد از خاکها بیش از 5 درصد بیشتر از مقدار واقعی اندازه­گیری می­کند و با ریز‏بافت شدن خاک میزان انحراف این روش از مقدار واقعی، افزایش می‏یابد. برای رفع مشکل، دو روش چهار قرائتی با طبقه‏بندی انجمن بین‏المللی علوم خاک (ISSS) شامل: الف) قرائت 2 و 10 دقیقه (برای تعیین مرز شن و سیلت) و 6 و 8 ساعت (برای تعیین مقدار رس) و ب) قرائت 2 و 10 دقیقه (برای تعیین مرز شن و سیلت) و 6 و 24 ساعت (برای تعیین مقدار رس)، پیشنهاد شد. روش پیشنهادی قرائت 2 و 10 دقیقه و 6 و 8 ساعت و روش پیشنهادی قرائت 2 و 10 دقیقه و 6 و 24 ساعت به­ترتیب در 1/97 و 2/94 درصد خاک­ها، کلاس بافت را به درستی نشان­ می­دهد و به ترتیب در بیش از 90 و 81 درصد موارد، خطای آنها در تعیین مقدار رس خاک کمتر از 1± درصد می­باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Comparison of Some Methods for Measuring Primary Soil Particle Size Distribution and Introducing Appropriate Times for the Four-Reading Method for Determining Soil Texture

نویسندگان [English]

  • Mortaza Yavari 1
  • Mohammad Hosein Mohammadi 2
  • Karim Shahbazi, 3
1 M.Sc. Student, Dep. of Soil Sciences and Engineering, Faculty of Engineering and Technology, University of Tehran, Karaj, Iran
2 Associate Professor Dep. of Soil Sciences and Engineering, Faculty of Engineering and Technology, University of Tehran, Karaj, Iran
3 Research Associate Professor, Soil and Water Research Institute, AREEO, Karaj, Iran
چکیده [English]

Different methods are used for determination of the primary particle size distribution (PSD) in Iranian soils laboratories, which in many situations makes it difficult to compare results and their precision. This research was conducted to achieve an easy and inexpensive strategy with acceptable accuracy. First, 112 soil samples from 16 different provinces of Iran with a wide range of soils were taken from different climates and land uses. Soil PSD was measured by hydrometer with and without cement removal. The results showed that the common reading method of 40 seconds and 2 hours (Bouyoucos, 1962) measures the clay fraction with an average absolute error of 9.5% as compared to the complete record method. This error was more than 10% in 40.5% of the proposed soils and more than 5% in 94.2% of the soils. The deviation of this method from the actual value is increased as the soil becomes finer. Two four-reading methods with the classification of International Soil Science Association (ISSS) including: a) 2 and 10 minute readings (to measure silt fraction) and 6 and 8 hours (to measure clay fraction), and b) readings of 2 and 10 minutes (to measure silt fraction) and 6 and 24 hours (to measure clay fraction) were suggested to determine the soil texture. The two later methods show the soil texture correctly in 97.1 and 94.2% of the soils, respectively. The error of these two methods for determination of clay fraction is less than % in more than 90 and 81% of the proposed soils, respectively.

کلیدواژه‌ها [English]

  • Particle size Distribution
  • Soil Texture
  • Densitometry
  • Hydrometer Method
Arya, L. M., and Paris, J. F. (1981). A physicoempirical model to predict the soil moisture characteristic from particle-size distribution and bulk density data 1. Soil Science Society of America Journal45(6), 1023-1030
Barthès, B. G., Kouakoua, E., Larré-Larrouy, M. C., Razafimbelo, T. M., de Luca, E. F., Azontonde, A. and Feller, C. L. (2008). Texture and sesquioxide effects on water-stable aggregates and organic matter in some tropical soils. Geoderma143(1-2), 14-25.
Blake, G. R., and Hartge, K. H. (1986). Bulk density 1. Methods of soil analysis: part 1-physical and mineralogical methods, pp.363-375.
Bouyoucos, G. J. (1962). Hydrometer method improved for making particle size analyses of soils 1. Agronomy Journal54(5), 464-465.
Beretta, A. N., Silbermann, A. V., Paladino, L., Torres, D., Bassahun, D., Musselli, R., and García-Lamohte, A. (2014). Análisis de textura del suelo con hidrómetro: modificaciones al método de Bouyoucus. Ciencia e Investigación Agraria41(2), 263-271.‏
Coates, G. F., and Hulse, C. A. (1985). A comparison of four methods of size analysis of fine-grained sediments. New Zealand Journal of Geology and Geophysics28(2), 369-380.
Cosby, B. J., G. M. Hornberger, R. B. Clapp and T. R. Ginn, 1984. A statistical exploration of the relationships of soil moisture characteristics to the physical properties of soils. Water Resour. Res., 20(6): 682-690.
Day, P. R. (1965). Particle fractionation and particle-size analysis (No. methods of soil an a, pp. 545-567). American Society of Agronomy, Soil Science Society of America.
De Oro, L.A., Colazo, J.C., Avecilla, F., Buschiazzo, D.E. and Asensio, C., (2019). Relative soil water content as a factor for wind erodibility in soils with different texture and aggregation. Aeolian Research, 37, pp.25-31.
Fredlund, M. D., Fredlund, D. G., and Wilson, G. W. (2000). An equation to represent grain-size distribution. Canadian Geotechnical Journal37(4), 817-827.
Jensen, D. K., Tuller, M., de Jonge, L. W., Arthur, E., and Moldrup, P. (2015). A new two-stage approach to predicting the soil water characteristic from saturation to oven-dryness. Journal of Hydrology521, 498-507.
Gee, G. W., And Bauder, J. W. (1979). Particle size analysis by hydrometer: a simplified method for routine textural analysis and a sensitivity test of measurement parameters 1. Soil Science Society of America Journal43(5), 1004-1007.
Gee, G. W., and Or, D. (2002). 2.4 Particle-size analysis. Methods of Soil Analysis. Part4(598), 255-293.
Holmgren, G. G. (1967). A rapid citrate-dithionite extractable iron procedure 1. Soil Science Society of America Journal, 31(2), 210-211.
Kaddah, M. T. (1975). The hydrometer method for particle-size analysis: 2. factors affecting the dispersive properties of glassy Na-polyphosphate in calcareous saline soil suspensions. Soil Science120(6), 412-420.
Kaddah, M. T. (1974). The hydrometer method for detailed particle-size analysis: 1. Graphical interpretation of hydrometer readings and test of method. Soil Science118(2), 102-108.‏
Karkanis, P. G., Au, K., and Schaalje, G. B. (1991). Comparison of four measurement schedules for determination of soil particle-size distribution by the hydrometer method. Canadian Agricultural Engineering33(2), 211-216.
Karup, D., Moldrup, P., Paradelo, M., Katuwal, S., Norgaard, T., Greve, M. H., and de Jonge, L. W. (2016). Water and solute transport in agricultural soils predicted by volumetric clay and silt contents. Journal of Contaminant Hydrology192, 194-202.
Lebron, I., Suarez, D. and Yoshida, T. (2002). Gypsum effect on the aggregate size and geometry of three sodic soils under reclamation. Soil Sci Soc Am J 66: 92-98.
Liu, T. K., Odell, R. T., Etter, W. C., and Thornburn, T. H. (1966). A Comparison of Clay Contents Determined by Hydrometer and Pipette Methods Using Reduced Major Axis Analysis 1. Soil Science Society of America Journal30(6), 665-669.
Page, A. L., Miller, R. H., and Keeney, D. R. (1982). Methods of Soil Analysis, part 2. Chemical and Microbiological Properties, 2.
Poeplau, C., Eriksson, J., and Kätterer, T. (2015). Estimating residual water content in air-dried soil from organic carbon and clay content. Soil and Tillage Research145, 181-183.
Schjønning, P., McBride, R. A., Keller, T., and Obour, P. B. (2017). Predicting soil particle density from clay and soil organic matter contents. Geoderma, 286, 83-87.
Shirazi, M. A., Boersma, L., and Johnson, C. B. (2001). Particle-size distributions. Soil Science Society of America Journal65(2), 300-310.
Skaggs, T. H., Arya, L. M., Shouse, P. J., and Mohanty, B. P. (2001). Estimating particle-size distribution from limited soil texture data. Soil Science Society of America Journal65(4), 1038-1044.
Thomas, G.W. (1996). Soil pH and soil asidity. p. 475-490. In: D.L. Sparks et al. (eds.). Method of Soil Analysis. Part 3. 3rd ed. Chemical and Microbiological Properties. ASA and SSSA, Madison, WI, USA.
USDI. (1982). Particle-size analyses. Chapter4 oflandclassi fication techniques and standards. Series 510. United States Department of the Interior. Washington, DC
Walkley, A., and Black, I. A. (1934). An examination of the Degtjareff method for determining soil organic matter, and a proposed modification of the chromic acid titration method. Soil Science, 37(1), 29-38.
Walter, N. F., Hallberg, G. R., and Fenton, T. E. (1978). Particle-size analysis by the Iowa State University soil survey laboratory. Standard procedures for evaluation of quaternary materials in Iowa. Technical Information Series, (8), 61-74.
WRB, I.W.G. (2014). World reference base for soil resources 2014. International Soil Classification System for Naming Soils and Creating Legends for Soil Maps, (106).
Yang, Y., Wang, L., Wendroth, O., Liu, B., Cheng, C., Huang, T., and Shi, Y. (2019). Is the Laser Diffraction Method Reliable for Soil Particle Size Distribution Analysis?. Soil Science Society of America Journal, 83(2), 276-287.‏
Yavari, M., Mohammadi. M.H., and Shahbazi, K. (2020) The effect of cement agents removal on soil texture measurement in Iran. Iranian journal of water and soil rearech. In Press. doi: 10.22059/ijswr.2020.280297.668188