Document Type : Research Paper

Authors

1 phd student of gorgan university of Agricultural Sciences and Natural Resources, Iran

2 Professor., Dept. of Soil Science, Gorgan University of Agricultural Sciences and Natural Resources, Iran

3 Associate Professor., Dept. of earth Science, Golestan University , Iran

4 Associate Professor, Department of Soil Science, Gorgan University of Agricultural Sciences and Natural Resources

Abstract

Introduction: loess are a special type of silty soil with a porous structure and poor cohesion, and often contain silt with minor amounts of clay to fine sand . These characteristics make loess among the problematic soils in terms of engineering geology. problematic soils are observed in different parts of the world including Australia, Brazil, New Zealand, the United States and many areas of Iran. Some fine-grained soils are structurally unstable, that is, they are easily dispersed and are highly erodible. Hence, presence of such soils in engineering and Agricultural projects can cause great damage and financial loss. One of the most important influencing factors in the vulnerability of loess soils is the dispersion phenomenon. Dispersion or colloidal erosion is a physical-chemical process that often occurs in fine-grained soils containing clay particles. In general, dispersion phenomena occur when the shear stress induced by the flow exceeds the friction among particles, causing surface abrasion. Erosion can extend itself along a drying crack, settlement, hydraulic fracture, or other high permeability channels in a soil mass. Dispersive loess soil easily and quickly separates and disperses from each other in water with low salt concentration without any special mechanical stimulation. Climate and physicochemical characteristics are two important factors in soil dispersive. which affect the degree of soil dispersive. Climate affects soil development by influencing physicochemical characteristics. On the other hand, soil texture, clay content, porosity and Bulk density, pH and solubility of salts in soil are closely related to dispersive. Although, extensive researches carried out to determine the dispersion potential of the soils, affecting factors on dispersion phenomenon and validation of the soil dispersion tests, no comprehensive studies have been performed on The effect of climatic characteristics loess soils in golestan province. Therefore, the aim of this research is to investigate the effect of climate and physicochemical characteristics on soil dispersive.

Materials and Methods: This research was focused on loess soils of Golestan province. seven pedons were selected, sampled and described in different parts of the province. Climatic data was prepared and physicochemical and dispersive analyzes were performed on soil samples. The values of pH, electrical conductivity, equivalent calcium carbonate, cation exchange capacity and bulk density were measured. In order to study the degree of divergence, Sherrard's chemical test and pinhole test were performed.

Results and Discussion: By investigating the amount of rainfall in different regions of the province, it was found that the loess soils of Golestan province are not in the same climatic conditions. The results showed that the climatic and physicochemical characteristics of the soils in interaction with each other had a significant effect on the evolution of the soil and the reduction of divergence in the studied soils. The highest amount of precipitation was in Ramyan and Minodasht region And these two regions had greater depth of soil and heavier texture than other pedons. The results of the pinhole test show these soils with intermadiate dispersion potential. While the results of the chemical test for most of the samples are non dispersive. According to the results obtained from the pinhole test, Minodasht and Sufian pedons with rainfall of 815.8 and 608.9 mm were completely non-divergent, and Hoten pedon with Aridic moisture regime and rainfall of 189.7 mm had the highest dispersion potential. In total, 30% of the horizons showed moderate dispersion. which were mostly in the Aridic moisture regime. The chemical test in this research also confirmed the presence of a small amount of sodium ion in the saturated soil extract, and only three horizons had the potential of chemical divergence based on the SAR level. From the results, it can be analyzed that the soil dispersion in this research is due to the physical nature of soil particles.

Conclusion: The review of climatic data and the results of physico-chemical tests showed the existence of direct coordination between the climatic and physico-chemical properties of the soil. So that with the increase of rainfall, the soil formation process increased. This means that in soils with xeric regime and high rainfall, the percentage of clay, organic matter, porosity and water retention in the soil has increased. As a result, the dispersion potential in these soils has decreased.

Keywords: Loess soils, Dispersive soil, Physicochemical dispersion, Pinhole test.

Keywords

Main Subjects

1. Afriani, L., and Perdana, R. 2022. The Identification of the Existence of Dispersive Soil on the Soft Soil for Dam Filling Material. Journal of Civil Engineering and Architecture, 10(1): 388-394.
2. Alvarez, R., and Lavado, R.S. 1998. Climate, organic matter and clay content relationships in the Pampa and Chaco soils, Argentina. Geoderma, 83:127–141.
3. Azimzadeh, Y., and Najafi, N. 2017. Effects of Biochar on Soil Physical, Chemical, and Biological Properties. Land Management Journal, 4(2):161-173. (in Persian)
4. Bagherifam, S,. Delavar, M A,. Keshavarz, P,. and Karami, P. 2022. Modeling the impact of climate change on soil organic carbon pools in the semi-arid climate of Mashhad using the RothC model. Iranian Journal of Soil and Water Research, 53 (10): 2349-2363. (In Persian)
5. Bahrami, K., Nikoodel, M.R., and Hafezi Moghadas, N. 2014. Investigating the engineering geological characteristics of loess soils north of Kalaleh in Golestan province with a Special attitude on erosion and erodibility. Iranian Journal of Geology, 8(29): 2-34. (In Persian)
6. Baik, M.H., and Lee, S.Y. 2010. Colloidal stability of bentonite clay considering surface charge properties as a function of PH and Ionic strength. Journal of Industrial and Engineering Chemistry, 16: 837-841.
7. Besharti, B., Abedini, M., and asaghari, S. 2018. Study and analysis of factors affecting the creation and development of gully erosion whatershed of shoor chai. Journal of Geographical Research. 33(2): 206 -222. (in Persian)
8. Bower, C.A., Reitmeir, R.F., and Fireman, M. 1952. Exchangeable cation analysis of saline and alkali soils. Journal of Soil Science, 73: 251-261.
9. Catt, J.A. 2001. The Agricultural Importance of Loess. Journal of Earth-Science Reviews. 54: 213-229.
10. Dai, W., Y.and Huang., Y. 2006. Relation of soil organic matter concentration to climate and altitude in zonal soils of China. Journal of Catena, 65: 87- 94.
11. Duiker, S.W., Flanagan, D.C., and Lal, R. 2001. Erodibility and filtration characteristics of five major soils of southwest Spain. Journal of Catena, 45: 103-121.
12. Eftene, A., Ignat, P., Chiurciu, I.A., Manea, A., Raducu, D., and Dumitru, S. 2020. Soil Bulk Density as important management factor and ecosystem services well function. Scientific Papers Series Management, Economic Engineering in Agriculture and Rural Development, 20(4): 175-184.
13. Fernando, J. 2010. Effect of water quality on the dispersive characteristics of soils found in the Morwell area, Victoria, Australia. Journal of Geotechnical and Geological Engineering, 28(6): 835-850.
14. Ghandhari, S., Amini, A., Solgi, A., and Rezaei, H. 2021. Fractal Analysis of Post-Deposition Changes of the Golestan Province's Loess Texture. Desert Ecosystem Engineering Journal, 10(31): 43-58. (In Persian)
15. Gidday, B., and Mittal, S. 2020. Improving the characteristics of dispersive subgrade soils using lime. Journal of Heliyon, 6(2): 1-7.
16. Gooderzi, A.R., and Ohadi, V.R. 2018. The Effect of anion type on the Dispersion ability and engineering properties of Montmorillonite clay. The 6th National Congress of Civil Engineering, Semnan University.
17. Harms, B., Dalal, R., and Pointon., S. 2002. Paired sites sampling to estimate soil organic carbon changes following land clearing in Queensland. Proceeding of 17th World Congress of Soil Science, 14-21 August, Thailand, 1128-1129.
18. Jafari Ardakani, A., Bayat, R., Peyrowan, H.R., Shariat Jafari, M. and Charkhabi, A.H., 2009. Investigating the state of erosion and sedimentation in the loess deposits of Golestan province. 6th Engineering Geology Conference, Tarbiat Modares University, 1161-1173. (In Persian)
19. Klute, A. 1986. Methods of Soil Analysis. part 1(Physical and Mineralogical Methods). 2nd Edition, Agronomy Monograph 9, American Society of Agronomy—Soil Science Society of America, Madison, 363-382.
20. Marchuk, A., Rengasamy, P., and McNeill, A. 2013. Influence of organic matter, clay mineralogy, and pH on the effects of CROSS on soil structure is related to the zeta potential of the dispersed clay. Journal of Soil Research, 51(1): 34- 40.
21. Mengel, K., and Rahmatullah Dou, H. 1998. Release of Potassium from the Silt and Sand Fraction of Loess-derived Soil. Journal of Soil Science, 163: 805-813.
22. Mohammadzadeh, A., and Azimzadeh, Y. 2023. The Effect of Climate Change on the Physical and Chemical Properties of Arid and Semi-Arid Soils. Journal of Water and Soil Resources Conservation, 12(3): 139-152.
23. Mohanty, S., Roy, N., Singh, S.P., and Sihag, P. 2019. Effect of industrial by-products on the strength of stabilized dispersive soil. International Journal of Geotechnical Engineering, 15(4): 405-417.
24. Moravej, S., Habibagahi, G., Nikooee, E., and Niazi, A. 2018. Stabilization of dispersive soils by means of biological calcite precipitation. Geoderma, 315(1) 130-137.
25. Nelson, R.E. 1982. Carbonate and gypsum. Methods of Soil Analysis. Part 2. Chemical and Microbiological Properties. American Society of Agronomy/Soil Science Society of America, Madison, Wisconsin, USA, 181-197.
26. Newhall, F., and Berdanier, C.R. 1996. Calculation of soil moisture regimes from the climatic record. Soil Survey Investigations Report No. 46, National Soil Survey Center, Natural Resources Conservation Service, Lincoln, NE, 1-35.
27. Ocheli, A., Ogbe, O.B., and Aigbadon, G.O. 2021. Geology and geotechnical investigations of the Anambra Basin, Southeastern Nigeria: implication for gully erosion Hazards. Environmental System Reaserch, 10(23): 1 -27.
28. Padyab, M. 2018. Simultaneous Impact of pH and Sodium Ion Concentration on the Dispersivity of Clayey Soils. Submitted in partial fulfillment of the requirements for the degree of Master of Science in Highway and Transportation. (In Persian)
29. Pittman, R., and Hu, B. 2020. Estimation of Soil Bulk Density and carbon using Multi-Source remotely sensed DATA. International Society for Photogrammetry and Remote Sensing, 3: 541-548.
30. Premkumar, S., Piratheepan, J., and Rajeev, P. 2017. Effect of brown coal fly ash on dispersive clayey soils. Proceedings of the Institution of Civil Engineers-Ground Improvement, 170(4): 231-244.
31. Roushangar, K., Alami, M. T., and Houshyar, Y. 2019. Experimental investigation of lime impact on self-healing and dispersion processes of clay soils (Case study: Gurdyan dam). Amirkabir Journal of Civil Engineering, 52(6): 1347-1360. (In Persian)
32. Sadeghi, H., Nasiri, H., Ali Panahi, P., and Sadeghi., M. 2020. Dispersivity, collapsibility and microstructure of a natural dispersive loess from Iran. The 16th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering.
33. Sebti, M., Khormali, F., Soltani, A., Eftekhari, K., Ghanghermeh, A., and dordipour, E. 2023. The effect of climate change on soil organic carbon storage using the Roth C model in the agricultural lands of Golestan province. Agricultural Engineering. 45(4): 339-355. (In Persian)
34. Schoeneberger, P.J., Wysocki, D.A., Benham, E.C., and Broderson, W,D. 2021. Field book for describing and sampling soils. Natural Resources Conservation Service, USDA, National Soil Survey Center, Lincoln, 2: 103-107.
35. Shabanzadeh, M., and Atrchian, M.R. 2021. Improving Behavioral properties of dispersive clay by Addition of Incinerated sewage sludge Ash and Hydrated Lime. AUT Journal of Civil Engineering, 5(1): 1-13.
36. Sherard, J.L., Dunnigan, L.P., and Decker, R.S. 1976. Pinhole Test for Identifying Dispersive Soils.Geotechnical Eng. Journal of American Society of Civil Engineers, 102(1): 69-85.
37. Vakili, A.H., Shojaei, I., Salimi, M., Selamat, M.R., and Farhadi, M.S. 2020. Contact erosional behavior of Foundation of pavement embankment constructed with nanosilica-treeted dispersive soils. Journal Soils and Foundations, 60(1): 167-178.
38. Zamanzadeh, M., and Akbari, M. 2012. The effect of physical and chemical characteristics of soil on the formation and expansion of trench erosion (Case study: Fars, Kahor Lamard Plain region). Quantitative Geomorphological Research, 2(2): 135-156. (In Persian)
39. Zare, M., Soufi, M., Nejabat, M., and Pourghasemi, H.R. 2020. The topographic threshold of gully erosion contributing factors. Journal of Natural Hazards, 112(1): 2013-2035.
40. Zhung, S.Y., Zhuo, M.N., Xie, Z.Y., Yuan, Z.J., Wang, Y.T., Hung, B., liao, Y.S., Li, D.Q., and Wang, Y. 2020. Effects of near soil surface components on soil erosion on steep granite red soil colluvial deposits. Geoderma, 365(3): 75-94.