Mineralogy of soils of major geomorphic units of north-eastern Haryana, India

Abstract

The study was carried to determine the mineralogy of soils of different geomorphic units for providing the more detailed information needed to improve agricultural production in north-eastern part of Haryana. The soils of the study area were slightly acidic to strongly alkaline in reaction (6-9.4). The cation exchange capacity and electrical conductivity varied from 3.10-26.80 cmol (+) kg-1 and 0.16-1.20 dSm-1, respectively. In general, the soils were siliceous in nature with SiO2 ranging from 68.60 to 87.90 percent. The soil samples from surface and subsurface diagnostic horizons were studied through X-ray diffraction. In fine sand, quartz was the dominant mineral followed by feldspars, muscovite, hornblende, tourmaline, zircon, biotite, iron ores and sphene. In silt fraction, quartz was the dominant mineral followed by mica, feldspars, chlorite, kaolinite, interstratified and traces of smectite and vermiculite. Semi-quantitative estimation of clay fraction indicated that illite was the single dominant mineral in the clay fraction of these pedons, however, its quantity was less in alluvial plains (28-30 %) compared to Shiwalik hills (36-49 %). Next to illite, a high amount of smectite (14-20 %) and vermiculite (11-17 %) were observed in clays of alluvial plains of Ghaggar (recent and old) whereas in Shiwalik hills (top and valley) these minerals were detected in small amount (6-11 %). Fairly good amount of kaolinite (10-17 %) and small amount of chlorite (4-11 %) were uniformly distributed in soil clays irrespective of geomorphic units showing their detrital origin. Medium intensity broad peaks in higher range diffractograms (14-24 AËš) indicated the presence of regular and irregular interstratified minerals in old alluvial plains of Ghaggar.