Sand Dune Soils of Semi-arid and Arid Agro-ecological Sub-regions of Punjab and their Characterization and Management

Sand dune areas in the semi-arid and arid agro-ecological sub-region covering a part of central and south-western Punjab were studied to generate comprehensive information on morphological, physico-chemical characteristics, constraints and potential of the soils. The dunal soils of semiarid and arid sub-regions are very deep, excessively drained, light yellowish brown to strong brown, sandy loam to sand, structureless and exhibit A-C horizon sequence. The soils of arid sub-region have relatively higher pH (7.8 to 8.5) than semi-arid soils due to calcareous nature of the former. The electrical conductivity (EC) is within the non-saline range (0.02 to 0.26 dS m⁻¹) in semi-arid soils, and non-saline to saline range (0.09 to 0.84 dS m⁻¹) in arid soils. The organic carbon (OC) content is low, both at surface and subsurface horizons (0.02 to 0.36%) having relatively higher OC in soils from semi-arid sub-region. The coarser textured soils have very low cation exchange capacity (CEC) [wt. mean = 1.4 to 4.4 cmol(p⁺)kg⁻¹] with calcium and magnesium as dominant cations on the exchange complex. The soils from semi-arid sub-region were classified as mixed, hyperthermic family of Typic Ustipsamments whereas that of arid sub-region keyed out as mixed, calcareous, hyperthermic family of Ustic Torripsamments. The soils from arid sub-region have relatively more limitations such as aridity, sandy texture, undulating topography, accumulation of calcium carbonate, hard concretionary substratum, moderate wind erosion and low CEC. Besides being low in fertility, these soils are more prone to micronutrient deficiency due to highly calcareous nature.