INVESTIGATING SOIL TEMPERATURE VARIABILITY AND THERMAL DIFFUSIVITY IN GRASS COWERED AND SHADED AREAS BY TREES

Changes in the soil temperature conditions are one of the most important components of soil microclimate and have a considerable impact on changes in soil properties and plant development processes. In this research, soil temperature and thermal diffusivity values were determined at two different fields which are grass covered and shaded areas by peach trees. Theoretical soil temperature values obtained from the solution of thermal conductivity equation were compared to experimental soil temperature values. Field studies were carried out on a farm field in Turkey, Samsun, Qaramba County, Yesilirmak neighborhood (36° 43.380' to the East, 41° 13.061' to the North) between August and September, 2011. Mean soil temperatures at the first experimental field covered by grass at 7:00, 12^л00, 18^л00 hours were determined as 19.5°C; 28.4°C; 23.4°C at the soil surface, 20.2°C; 26.9°C; 23.3°C at 10 cm, 20.7°C; 26.0°C; 23.1°C at 20 cm, 21.1°C; 25.3°C, 22.9°C at 30 cm and 21.4°C; 24.9°C; 22.9°C at 40 cm soil depth, respectively. Mean soil temperatures at the second experimental field shaded by peach trees at 7:00, 12:00, 18:00 hours were determined as 19.4°C; 24.7°C; 22.5°C at the soil surface, 20.3°C; 24.5°C; 22.7°C at 10 cm, 20.8°C; 24.1°C; 22.6°C at 20 cm, 21.1°C; 23.7°C; 22.4°C at 30 cm and 21.0°C; 23.5°C; 22.2°C at 40 cm soil depth, respectively. Mean thermal diffusivity in the 1st experimental field from 0 to 40 cm soil layer were 0.460 cm² s-1; 0.029 cm² s-1 and 0.167 sm² s-1 at 700, 1200 and 1800 hours, respectively. Mean thermal diffusivity in the 2^nd experimental field from 0 to 40 cm soil layer were 0.234 cm² s-1; 0.115 cm² s-1 and 1.677 cm² s-1at 7:00, 12:00 and 18:00 hours, respectively. The mean relative errors between the estimated results using the solution of heat conductivity equation and the experimental temperature measurements were 0.089 at the soil surface and 0.055 at 20 cm soil depth. Comparison of the experimental temperature measurements to estimated temperature values showed that the initial unconditional solution of the heat conductivity equation in a short period (< 3 days) gives much better periodic thermal changes on the soil surface and in soil layers.

soil temperature, thermal diffusivity, heat conductivity equation, measured and estimated temperatures

1. Allison, L. E., Moodie, C. D., 1965. Carbonate. In: C. A. Black et all (ed). Methods of Soil Analysis, Part 2. Agronomy 9:1379-1400. American Socety Of Argon., Inc., Madison, Wisconsin, USA.

2. Andry, H., Yamamoto, T., Irie, T., Moritani. S., Inoue, M., Fujiyama. H., 2009. Water retention. hydraulic conductivity of hydrophilic polymers in sandy soil as affected by temperature and water quality. Journal of Hydrology, 373: 177-183.

3. Anonymous, 1984. Samsun ili Verimlilik Envanteri ve Gubre ihtiyaci Raporu.Yayin No:23. Genel Yayin No:760, Ankara.

4. Arkhangel'skaya, T.A., 2004. Thermal diffusivity of gray forest soils in the Vladimir Opolie region. Pocvovedeniye, 3: 332-342.

5. Arkhangelskaya, T.A., 2014. Diversity of thermal conditions within the paleocryogenic soil complexes of the East European Plain: The discussion of key factors and mathematical modeling. Geoderma, 213: 608-616.

6. Arkhangel'skaya, T.A., Guber, A.K., Mazirov, M.A., Prokhorov, M.V., 2005. The temperature rejime of soils in Vladimir Opol'e Region. Pocvovedeniye, 7: 832-843.

7. Arkhangel'skaya, T.A., Umarova, A.B., 2008. Thermal diffusivity and temperature regime of soils in large lysimeters of the experimental soil station of Moscow State University. Pocvovedeniye, 3: 311-320.

8. Bayrakli, F., 1987. Toprak ve Bitki Analizleri. 19 Mayis Universitesi Ziraat Fakultesi Yayinlari No: 17, Samsun.

9. Black, C.A., 1957. Soil Plant Relationships. John Wiley and Sons. Inc., New York, 332 pp.

10. Chow, T.T., Long, H., Mok, H.Y., Li, K.W., 2011. Estimation of soil temperature profile in Hong Kong from climatic variables. Energy and Buildings, 43: 3568-3575.

11. Cichota, R., Elias, E.A., de Jong van Lier, Q., 2004. Testing a finite-difference model for soil heat transfer by comparing numerical and analytical solutions. Environmental Modelling & Software, 19: 495-506.

12. Constantz, J., 1982. Temperature dependence of unsaturated hydraulic conductivity of two soils. Soil Science Society ofAmerica Journal, 46: 466-470.

13. Demiralay, i. 1993. Toprak Fiziksel Analizleri. Ataturk Universitesi Ziraat Fakultesi Yayinlari. 143: 6-51, Erzurum.

14. Dinf, U., §enol,S., 1997. Toprak Etud ve Haritalama. £.U. Ziraat Fakultesi Genel Yayin No:161, Ders Kitaplari Yayin No: 50, Adana, 235 s.

15. Ekberli, I., 2006a. Determination of initial unconditional solution of heat conductivity equation for evaluation oftemperature variance in finite soil layer. J. of Applied Sci., 6(7): 1520-1526.

16. Ekberli, i., 2006b. Isi iletkenlik denkleminin fozumune bagli olarak topraktaki lsi ta§mimma etki yapan bazi parametrelerin incelenmesi. O.M.U. Zir. Fak. Dergisi, 21(2): 179189.

17. Ekberli, I, 2010. The possibility of mathematical model application in evaluation of underground water's nourishment via infiltration. International Soil Science Congress on ’’Management of Natural Resources to Sustain Soil Health and Quality”. May 26-28, 2010. Ondokuz Mayis University, Samsun-Turkey. pp. 793-801.

18. Ekberli, i., Gulser, C., Korkmaz, A., Ozdemir, N., A§km, T., Mikayil, F., 2002. Toprak olu§um enerjisinin teorik incelenmesi. Su Havzalarinda Toprak ve Su Kaynaklarinin Korunmasi. Geli§tirilmesi ve Yonetimi Sempozyumu. 18 - 20 Eylul 2002. Antakya/HATAY, s. 489-494.

19. Ekberli, i., Gulser, C., Ozdemir, N., 2005. Topraklarin termo-fiziksel ozellikleri ve isisal yayinim katsayisinin degerlendirilmesi. O.M.U. Zir. Fak. Dergisi, 20(2): 85-91.

20. Ekberli, i., Gulser, C., Ozdemir, N., 2011. Toprakta isi ta§iniminin matematiksel modellenmesi. Ulusal Toprak ve Su Sempozyumu, 25-27 Mayis 2011, Ankara, s. 237-243.

21. Evett, S.R., Agam, N., Kustas, W.P., Colaizzi, P.D., Schwartz, R.C., 2012. Soil profile method for soil thermal diffusivity, conductivity and heat flux: Comparison to soil heat flux plates. Advances in Water Resources, 50: 41-54.

22. Flerchinger, G. N., Pierson, F.B., 1997. Modelling plant canopy effects on variability of soil temperature and water: model calibration and validation. Journal of Arid Environments, 35: 641-653.

23. Gao, Z., Bian, L., Hu, Y., Wan, L., Fan, J., 2007. Determination of soil temperature in an arid region. Journal of Arid Environments, 71: 57-168.

24. Ghee, C., Neilson, R., Hallet, P.D., Robinson, D., Paterson, E., 2013. Priming of soil organic matter mineralisation is intrinsically insensitive to temperature. Soil Biology & Biochemistry, 66: 20-28.

25. Guntinas, M.E., Leiros, M.C., Trasar-Cepeda, C., Gil-Sotres, F., 2012. Effects of moisture and temperature on net soil nitrogen mineralization: A laboratory study. European Journal of Soil Biology, 48: 73-80.

26. Guo, J., Yang, Y., Chen, G., Xie, J., Yang, Z., 2014. Carbon mineralization of Chinese fir (Cunninghamia lanceolata) soils under different temperature and humidity conditions. Acta Ecologica Sinica, 34: 66-71.

27. Gulser, C., Ekberli.i., 2002. Toprak sicakliginin profil boyunca degi§imi. O.M.U. Zir. Fak. Dergisi, 17(3): 43-47.

28. Gulser, C., Ekberli, I., 2004. A comparison of estimated and measured diurnal soil temperature through a clay soil depth. J. of Applied Sci., 4(3): 418-423.

29. Hassan, W., David, J., Farhat Abbas, F., 2014. Effect of type and quality of two contrasting plant residues on CO emission potential ofUltisol soil: Implications for indirect influence oftemperature and moisture. Catena, 114:90-96.

30. Hillel, D., 1982. Introduction to Soil Physics. Academic Pres, inc. San Dieoga, California, USA, 364 p.

31. Hillel, D., 1998. Environmental Soil Physics. Academic Press, New York, 771 p.

32. Hopmans, J.W., Dane, J. H., 1985. Effect of temperature-dependent hydraulic properties on soil water movement. Soil Science Society ofAmerica Journal, 49: 51-58.

33. Jaynes, D.B., 1990. Temperature variations effect on field-measured infiltration. Soil

34. Science Society ofAmerica Journal, 54: 305-312.

35. Kacar, B., 1994. Bitki ve Topragin Kimyasal Analizleri III. Toprak Analizleri. A.U. Ziraat F akultesi Egitim, Ara§tirma ve Geli§tirme Vakfi Yayinlari, No:3: 89-98, Ankara.

36. Krzysztof, M., Bronislaw, W., Szymanski, W., Muskala. P., 2014. Soil moisture and temperature variation under different types of tundra vegetation during the growing season: A case study from the Fuglebekken catchment, SW Spitsbergen. Catena, 116:10-18.

37. Lei, S., Daniels, J. L., Bian, Z., Wainaina, N., 2011. Improved Soil Temperature Modeling. Environmental Earth Sciences, 62(6): 1123-1130.

38. Li, L.-J., You, M.-Y., Shi, H.-A., Ding, X.-L., Qiao, Y.-F., Han, X.-Z., 2013. Soil CO2 emissions from a cultivated Mollisol: Effects of organic amendments, soil temperature, and moisture. European Journal of Soil Biology, 55: 83-90.

39. Nerpin, S.V., Chudnovskii, A. F., 1984. Heat and Mass Transfer in the Plant-Soil-Air System. Translated from Russian. Published for USDA and National Sci. Found., Washington. D.S., by Amerind Publishing Co. Pvt. Ltd., New Delhi, India, 355 pp.

40. Onder, O., Ozgener, L., Tester, J.W., 2013. A practical approach to predict soil temperature variations for geothermal (ground) heat exchangers applications. International Journal of Heat and Mass Transfer, 62: 473-480.

41. Ponomoryov, D.G., Nadirov, F.D., Ekberov i.A., 1984. Topragin lsi mubadelesi denklemi. Azerbaycan SSC Bilimler Akademisinin Genel Dergisi, XL (11): 86-90.

42. Richards, L.A., 1954. Diagnosis and improvement of Saline and Alkali Soils. U.S.Dept. Agr. Handbook, 60: 105-106.

43. Schachtschabel, P., Blume, H.-P., Brummer, G., Hartge, K.-H., Schwertmann, U., 2001. Toprak Bilimi (£evirenler: Ozbek, H., Kaya, Z., Gok, M., Kaptan, H.). £.U. Ziraat Fak. Genel Yayin No: 73, Ders Kitaplari Yayin No: A-16, s. 349-361.

44. Schutt, M., Borken, W., Spot, O., Stange, C.F., Matzner, E., 2014. Temperature sensitivity of C and N mineralization in temperate forest soils at low temperatures. Soil Biology & Biochemistry, 69: 320-327.

45. Sterling, A.T., Jackson, R.D., 1986. Temperature. In: Klute, A. (Ed.), Methods of Soil Analysis Part 1. Physical and Mineralogical Methods. Agronomy Monograph No: 9, ASA, SSSA, Madison WI.

46. Tanaka, K., Hashimoto, S., 2006. Plant canopy effects on soil thermal and hydrological properties and soil respiration. Ecological Modelling, 196: 32-44.

47. Terrence, H.B., Hugh, A.L.H., 2011. Fine scale variability in soil extracellular enzyme activity is insensitive to rain events and temperature in a mesic system. Pedobiologia, 54: 141-146.

48. Tihonov, A.N., Samarskiy, A. A., 1972. Uravneniya Matemati?eskoy Fiziki. Nauka Press, Moscow, 735 s (s. 246-250).

49. Tikhonravova, P. I., 2007. Effect of the water content on the thermal diffusivity og clay loams with different degrees of salinization ih the Transvolga region. Pocvovedeniye, 1: 55-59.

50. Tikhonravova, P.I., Khitrov, N.B., 2003. Estimation of thermal conductivity in Vertisols of the Central Ciscaucasus region. Pocvovedeniye, 3: 342-351.

51. Wang,C., Wan, S., Xing, X., Zhang, L., Han, X., 2006. Temperature and soil moisture interactively affected soil net N mineralization in temperate grassland in Northern China. Soil Biology & Biochemistry, 38: 1101-1110.

52. Zibilske, L.M., Makus, D.J., 2009. Black oat cover crop management effects on soil temperature and biological properties on a Mollisol in Texas, USA. Geoderma, 149: 379-385.