No abstract

No abstract

The mineralogical compositions along with physical, chemical, elemental and mineralogical properties of four pedons occurring along a toposequence in Chhota Urla village (Abhanpur tehsil), Raipur district of Chhattisgarh state were studied. Landform had significant influence on physical, chemical, elemental and mineralogical properties of soils. Sand content decreased from higher topography to lower topography but clay content increased with decrease in elevation. pH of pedons ranged from strongly acid to moderately alkaline and CEC increased from upland to lowland. Quartz being dominant in sand fraction and absence of primary minerals like Ca-feldspar, K-feldspar indicated intense weathering of soils. Silt had quartz as dominant mineral followed by Ca- feldspar and K-feldspar. Kaolin was dominant mineral in clay fractions of pedons l and 2 (PI and P2) with sub-ordinate amount of smectite while smectite was dominant in other two pedons followed by kaolin. Huge amount of smectite which is first weathering product of plagioclase, did not find its parental legacy with underlying geology (sandstone, limestone and shale sequence) indicative of mixed alluvium, eroded from different geological formation and contradicted the occurrence of catenary sequence as reported earlier.

Soil salinity is a major environmental hazard which adversely affects plant growth, crop production, soil and water quality and agricultural productivity.Soil salinity is determined by measuring electrical conductivity of soil water suspension. Though saturation paste ECe closely relates with plant growth and development but its measurement is laborious and time-consuming specifically in clayey soils when large number of samples are analyzed. Measurement of EC1:2 (1:2 Soil: water suspension) is very quick and economical. Therefore, a need is felt to develop a relationship between ECe and EC1:2so that the values of EC1:2 could easily be related to ECe. For this, anexperiment was conducted on four soil series representing swell-shrink soils. Soils were artificially salinized with solutions (salt) of 0.2, 0.5, 1 and 2% of chloride salts (NaCl, CaCl2, MgCl2 and their mixture) and replicated three times. The results indicate that a significant relationship (r=0.96) exists between ECe and soil EC1:2and soil ECe can be reliably predicted from EC1:2 in swell-shrink soils.

No abstract