Clay Mineralogy Investigation In The Soils Of Arid Almanaqil Ridge, Gezira State, Sudan, Using Xrd Diffractograms
Elhag A.M.H, Ibrahim M.M.M, Ibrahim S.I, Dafalla M.S
Keywords: Arid soils, Clay mineralogy, Vertisols and X-ray diffractograms.
Abstract: Clay mineralogy was studied in the soils of Arid Almanaqil Ridge. The soils are classified according to the American System (Keys to Soil Taxonomy, 2010) in the fallowing families: Fine loamy, mixed, isohyperthermic, TypicHaplustepts (unit1, sample A1 and A2), Fine, mont, superactive, Isohyperthermic, VerticHaplocambids (unit2, sample A3) and Fine, mont, superactive, isohyperthermic, TypicHaploustert (unit3, sample A4). Representative soil samples were collected from these units. These samples were samples A1 and A2 for unit1, sample A3 for unit 2 and sample A4 for uint3 respectively. Those samples were compared with samples from outside the study area from north of the study area (sample A5 and A6) and from the alluvium of the Blue Nile (sample A7), according to their lithology, topographic position, soil types and soil mapping units. Clay mineralogy of the samples was studied using X-ray diffractograms (XRD) techniques. The XRD diffractograms indicated the presence of smectite, chlorite, illite, and kaolinite as the major clay minerals in the soil of the study area and outside of the study area. The major clay minerals in these soils, Chlorite, illite and kaolinite could have originated from parent material. Smectite, showed an increasing trend in samples A7 (outside of study area) and sample A4 (unit 3). The CEC of clay minerals in unit 1 and 2 were less than 50 Cmol+/kg , which indicated that minerals with low CEC were dominant this result conformed with the XRD results that showed dominance of Chlorite, illite, and Kaolinite. Higher CEC values (more than 50 Cmol+/kg) of the clay were encountered in soils samples from unit3 (A4) and those from outside study area (Sample A7), XRD results showed that the samples were dominated by smectite. Moreover, the CEC values of clay minerals were consistent with results of XRD. The X-ray mineralogy indicated that the Vertisols and Aridisols of the study area had the same origin as that of the Gezira soils.
 Wilson, M. J. 1999. The origin and formation of clay minerals in soils: past, present and future perspectives. Clay Miner. 34: 7-24.
 Abtahi, A. 1980. Soil genesis as affected by topography and time in calcareous parent materials. J.Soil Sci. Soc. Am. 44: 329 -336.
 Gharaee, H. A., and R. A. Mahjoory. 1984.Characteristica and geomorphic relationships of some representative Aridisols in southern Iran. Soil Sci. Soc. Am. J. 48: 115 -119.
 Khormali, F., and A. Abtahi. 2003. Origin and distribution of clay minerals in calcareous arid and semi-arid soils of Fars province. Clay Miner. 38: 511 -527.
 Wliaie, H. R., A. Abtahi, and R. J. Heck. 2006. Pedogenesis and clay mineralogical investigation of soils formed on gypsiferous and calcareous materials, on a transect, southwestern Iran. Geoderma 134: 62-81.
 Millot, G. 1970. Geology of clays. Masson et Cie., Paris.
 Abtahi, A. 1977.Effect of a saline and alkaline ground water on soil genesis in semiarid southern Iran.J.Soil Sci. Soc. Am. 41: 583-588.
 Abtahi, A., and F. Khormali. 2001. Genesis and morphological characteristics of Mollisols formed in a catena under water table influence in southern Iran. Commun. Soil Plant. 32: 1643-1658a.
 Sawhney, B. L. 1989. Interstratification in layer silicates. In: J. B., Dixon, and S. B. Weed, (eds.), Minerals in Soil Environment. Soil Sci. Soc. America, Madison, WI, pp. 789-828.
 Keys to Soil Taxonomy (2010).Soil Survey Staff.a basic system of soil classification for making and interpreting soil surveys, 11 edition. Agricultural Handbook 436, Natural Resources Conservation Service, USDA, Washington DC, USA, pp. 869.
 Ibrahim,M.M.M (2013). Spatial Variability and Land Evaluation of the Soils of Almanaqil Ridge, Gezira State, Sudan (Thesis, PhD) submitted to University of Khartoum, Khartoum, Sudan.
 Davies HRJ (1964). An agricultural revolution in the African tropics, the development of mechanized agriculture on the clay plains of the Republic of Sudan.Tijdshriftvoor econ.Ensoc.Geografie, pp. 101- 108.
 Meteorology Office-Gezara (1994). Rainfall records 1922-1994.
 Kittrick J.A. and E.W. Hope, 1963.A procedure for the particle size separation of soils for X-ray diffraction analysis. Soil Sci., 96: 312 -325.
 Page, A. L.;Miller, R. H. and Ceaney, D. R. (1982). Methods of Soil Analysis.Part 2. Chemical and Microbiological Properties, 2nd edition, American Society of Agronomy, Inc., Soil Science Society of America, Inc., Wisconsin, USA.
 Hag Abdulla, H. (1983).Profile development in arid and semi-arid tropical environment.Annual Report of the Gezira Research Station and Substations, ARC, Medani, Sudan.
 El-Attar, A. and Jackson, M. (1973). Montmorillonite soils developed in Nile River sediments. Soil Science 116,191-201.
 Senkayi, A. L.; Dixon, J. B.; Massner, L. R. and Viani, B. E. (1983). Mineralogical transformations during weathering of lignite overburden in East Texas. Clay and Clay Minerals 31(1), 49-56.
 Altaner SP, Hower J, Whitney G, Aronson JL. (1984). Modelfor K-bentonite formation: Evidence from zoned K-benton-ites in the disturbed belt, Montana. Geology 12:412-415.
 Osman, M.R., 1996. Recent to Quaternary river Nile sediments: A sedimentological characterization on samples from Aswan to Naga-Hamadi, Egypt. Ph.D. Thesis, University of Vienna, Austria, pp: 301.