تخمین نقطه ای منحنی رطوبتی خاک با استفاده از برخی ویژگی‌های فیزیکی و مکانیکی خاک

نوع مقاله: مقاله پژوهشی

نویسندگان

1 کارشناسی ارشد دانشگاه زنجان

2 گروه علوم خاک، دانشکده کشاورزی و منابع طبیعی، دانشگاه تهران

3 استادیار، گروه خاکشناسی، دانشگاه زنجان

چکیده

منحنی رطوبتی از ویژگی‌های بنیادی خاک بوده که برای شبیه‌‌سازی جریان آب و انتقال توأمان آب و املاح در بخش غیراشباع خاک کاربرد دارد. بدلیل وقت‌گیر و پرهزینه بودن اندازه‌گیری منحنی رطوبتی خاک، امروزه روش‌های غیرمستقیم مورد توجه قرار گرفته است. پژوهش حاضر با هدف تخمین منحنی رطوبتی خاک با استفاده از حدود آتربرگ و برخی ویژگی‌های فیزیکی خاک برنامه‌ریزی شد. در این پژوهش تعداد 43 نمونه خاک از مناطق شمال‌غرب ایران برداشت شد به طوری‌که 28 نمونه برای توسعه مدل‌ها و 15 نمونه بمنظور ارزیابی اعتبار مدل‌ها مورد استفاده قرار گرفت. منحنی رطوبتی خاک در مکش‌های (1/0، 2/0، 3/0، 4/0، 1، 2، 3، 5، 10 و 15 بار) و ویژگی‌های فیزیکی و حدود آتربرگ خاک‌ها به روش-های استاندارد اندازه‌گیری شد. پس از بررسی همبستگی بین متغیرهای مستقل و ترکیبی در محیط نرم افزار SPSS با روش رگرسیون گام به گام، مناسب‌ترین ترکیب از متغیرهای مستقل انتخاب و معادله رگرسیونی چند متغیره برای تخمین منحنی رطوبتی ارائه شد. نتایج نشان داد که از بین ویژگی‌های اندازه‌گیری شده، درصد رس، جرم ویژه ظاهری، حد روانی و خمیری بیش‌ترین همبستگی را با مقدار رطوبت داشتند. مقادیر آماره‌های ضریب تبیین (89 درصد) و مجذور میانگین مربعات خطا (028/0) حاصل از تجزیه‌های آماری در کلیه مکش‌ها نشان دهنده اعتبار بالای توابع پیشنهادی برای تخمین منحنی رطوبتی می‌باشد.

کلیدواژه‌ها


عنوان مقاله [English]

Point estimation of soil moisture characteristics curve using some soil physical and mechanical properties

نویسنده [English]

  • Mohammad Hossein Mohammadi 2
2 Department of Soil Science, Agriculture and Natural Resources Faculty, University of Tehran
چکیده [English]

Soil moisture characteristic curve (SMC) is a fundamental soil property for predicting and modeling water flow and solute transport in the unsaturated soil, but its direct measurement is tedious and time consuming. Therefore, various indirect methods (e.g., pedotransfer functions, PTFs) have been developed to predict SMC from easily available soil properties (EASP). We develop a procedure to predict SMC from ESAP and soil liquid limit (LL), and plastic limit (PL). Forty three soils were sampled from north-west of Iran. All of soil samples were divided in two groups; 28 and 15 soils samples were used to train and evaluate of the models, respectively . The SMC, (water content at the suctions 0.1, 0.2, 0.3, 0.4, 1, 2, 3, 5, 10 and 15 bar) and LL, PL and ESAP were measured through standard methods. Multiple linear regression analysis was used to make correlation between LL, PL and ESAP data as independent variables along with SMC data as the dependent variable, using the SPSS software and the stepwise algorithm. Results showed that among all measured soil properties, the clay content, bulk density, LL and PL had high correlation with the soil moisture content at different suction heads. Values of the coefficient of determination (89%) and root mean square error (0.028), obtained by the statistical analysis, indicated the validity of the models in the all of the suction heads.

کلیدواژه‌ها [English]

  • Atterberg limits
  • Point pedotransfer functions
  • Soil water-transmission
  • soil properties
  • Unsaturated soil
Abbasi F. Advanced Soil Physics. 2007. 1nd Ed. Tehran University Press, 260p. (In Persian)

Aina P.O., and Periaswamy S.P. 1985. Estimating available water-holding capacity of western Nigerian soils from soil texture and bulk density, using core and sieved samples. Journal of Soil Science, 140:55-58.

Alkhafaji A., and Andersland O. 1992. Equations for Compression Index Approximation. Journal of Geotechnical Engineering, 118(1): 148-153.

Archer J.R. 1975. Soil consistency. In: Soil physical conditions and crop production. Technical Bulletin 29, Ministry of Agriculture, Fishers and food, HMSO, London, pp. 289-297.

ASTM (American Society for testing and Materials). 2010. Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils. ASTM Designation, D4318-05.

Bayburdi M. 2014. Soil Physics. 7nd Ed. Tehran University Press, 671p. (In Persian)

Blake G.R., and Hartge K.H. 1986. Bulk density. In: Klute A. (Ed.).  Methods of Soil Analysis. Part 1, 2nd , Agronomy. Monograph. 9. American Society of Agronomy, Madison, WI, pp. 363-375.

Carter M.R. 1993. Soil Sampling and Methods of Analysis. Lewis Publishing, 823p.

Cazemier D.R., Lagacherie P., and Clouaire R.M. 2001. A possibility theory approach for estimating available water capacity from imprecise Information contained in soil data bases. Geoderma, 103: 113-132.

Danalatos N.G., Kosmas C.S., Driessen P.M., and Yassoglou N. 1994. Estimation of the draining soil moisture characteristics from standard data as recorded in soil surveys. Geoderma, 64: 155-165.

Davidson D.T., and Sheeler J.B. 1952. Clay Fraction in Engineering Soils: Influence of Amount on Properties. Proceedings of the Highway Research Board, pp. 558-563.

Desbarats A.J. 1995. Upscaling capillary pressure–saturation curves in heterogeneous porous media, Geoderma, 31: 281-28.

Farrokhian Firuzi A., and Homaee M. 2005. Predicting water retention curve of gypsiferous soils using the derived point pedotransfer functions. Journal of Agricultural engineering Research, 6(24): 129-142. (In Persian)

Ghorbani Dashtaki S., Homaee M., and Khodaverdiloo H. 2011. Derivation and validation of pedotransfer functions for estimating soil water retention curve using a variety of soil data. Soil Use and Management, 26: 68-74.

Grimshaw R.W. 1971. The chemistry and physics of clays. 4th Ed, Wiley Inter-science, New York,1024p.

Haverkamp R., Leij F.J., Fuentes C., Sciortino A., and Ross P.J. 2005. Soil water retention. Introduction of shape index. Soil Science Society of America Journal, 69: 1881-1890.

Huang G.H., Zhang R. D., and Huang Q. Z. 2006. Modeling soil water retention curve with a fractal method. Pedosphere, 16: 137-146.

Jana R.B., Mohanty B. and Springer E.P. 2007. Multiscale pedotransfer functions for soil water retention. Vadose Zone Journal, 6: 868-878.

Kawano Y., and Holmes W.E. 1958. Compaction tests as a means of soil structure evaluation. Soil Science Society of America Journal, 22: 369-372.

Kern J.S. 1995. Evaluation of soil water retention models based on basic soil physical properties. Soil Science Society of America Journal, 59: 1134-1141.

Khodaverdiloo H., Homaee M., van Genuchten M.T., and Ghorbani Dashtaki S. 2011. Deriving and validating pedotransfer functions for some calcareous soils. Journal of Hydrology, 399: 93-99.

Klute A., and Dirksen C. 1986. Hydraulic conductivity and diffusivity: Laboratory methods. In: Klute A. (Ed). Method of Soil Analysis, Part 1. Agronomy Soil Science Society of America Madison.W.I, pp. 687-734.

Lal R. 1979. Physical properties and moisture retention characteristics of some Nigerian soils. Geoderma, 21: 209-223.

Livneh M., Kinsky J., and Zaslavsky D. 1970. Correlation of suction curves with the plasticity index of soils. Journal of Materials, JMLSA, pp. 209-220.

Malkawi A.I.H., Alawneh A.S., and Abu-Safaqah O.T. 1999. Effects of organic matter on the physical and the physicochemical properties of an illitic soil. Applied Clay Science, 14: 257-278.

Mir Mohammad Hosseini S.M., Ganjian N., and Pashang Pisheh Y. 2011. Estimation of the water retention curve for unsaturated clay. Canadian Journal of Soil Science, 91:543-549.

Mosaddghi M.R., Hajabbasi M.A., Hemmat A., and Afyni M. 2000. Soil compactibility as affect by soil moisture content and farmyard manure in central Iran. Soil Tillage Research, 55: 87-97.

Mulqueen J. 1976. Plasticity Characteristics of Some Carboniferous Clay soils in north central Ireland and their significance. Irish Journal of Agricultural Research, 15(1): 129-136.

Nath A., and Dalal S.S. 2004. The role of plasticity index in predicting compression behavior of clays, Electronic Journal of Geotechnical Engineering, vol. 9, Bundle E.

Odell R.T., Thornburn I. H., and McKenzie L. J. 1960. Relationships of Atterberg limit to some other properties of Illinois soils. Soil Science Society of America Journal, 24: 297-300.

Rawls W.J., and Pachepsky Y.A. 2002. Soil consistence and structure as predictors of water retention. Soil Science Society of America Journal, 66: 1115-1126.

Rawls W.J., Brakensiek D.L., and Saxton K.E. 1982. Estimation of soil water properties. American Society of Agricultural and Biological Engineers, 25: 1316-1320.

Rawls W.J., Brakensiek D.L., and Soni B. 1983. Agricultural management effects on soil water processes: Soil water retention and Green and Ampt infiltration parameters. American Society of Agricultural and Biological Engineers, 26:1747-1752.

Reichert J.M., Aluquerque J.A., Kaiser D.R., Reinert D.J., Urach F.L., and Carlesso R. 2009. Estimation of water retention and availability in soils of Rio Grande Do Sul. Revista Brasileira de Ciência do Solo, Brazil, 33: 1547-1560.

Rowell D.L., 2014. Soil science: Methods & applications. Longman Scientific & Technical, 350p.

Russell E.R., and Mickle J.L. 1970. Liquid limit values by soil moisture tension. Journal of the Soil Mechanics and Foundations Division, 96: 967-989.

Seed H.B., Woodward R.J., and Lundgren R. 1964. Fundamental aspects of the atterberg limits. Journal of Soil Mechanics and Foundations Division, 90(6): 75-105.

Shirani H., and Rafinejad N. 2011. Prediction of some costly measured properties using neural network and statistical regression in Kerman area. Journal of Soil Research, 25(4): 350-359. (In Persian)

Tomasella J., Pachepsky Y., Crestana S., and Rawls W.J. 2003. Comparison of two techniques to develop pedotransfer functions for water retention. Soil Science Society of America Journal, 67: 1085–92.

Tuller M., Or D., and Dudley L.M. 1999. Adsorption and capillary condensation in porous media: Liquid retention and interfacial configuration in angular pores. Water Resource Research, 35(7): 1949-1964.

Vepraskas M.J. 1992. Redoximorphic features for identifying aquic conditions. Issue 301 of Technical bulletin (North Carolina Agricultural Research Service), 33p.

Walczak R., Witkowska-Walczak B., and Sławinski C. 2004. Pedotransfer studies in Poland. In: Pachepsky Y.A. and Rawls W.J. (Ed.). Development of pedotransfer functions in soil hydrology). Developments in Soil Science, 30: 449-463.

Weynants M., Vereecken H., and Javaux M. 2009. Revisiting vereecken pedotransfer functions: Introducing a closed-form hydraulic model. Vadoze Zone Journal, 8(1): 86-95.