Sandy soil

Distribution

         A large tract of the hot and arid region, with a plant growing period of less than 60 days in a year and situated in the NW India between  the Aravalli hills and the Indus river, have desertic conditions of recent origin. These soils occupy 29 m.ha in the total geographical area

Salient Characteristics

•      The soils are sandy to loamy fine sand in texture, with clay content ranging from about 3.5 to 10 percent

•      These are pale brown to yellowish brown in colour and are either single grained or have weak , fine subangular blocky structure

•      They are slightly to moderately alkaline in reaction (pH 7.8 -9.0) because of their calcareous nature.  Calcitic nodules are present

•      The hyper aridic areas such as Bikaner, Jaisalmer in Rajasthan are gypsiferous in nature and may form a gypsic horizon in the subsurface soils. They need special attention to avoid formation of sink holes, if irrigated for growing crops.

•      These soils are poor in nutrient and water holding capacity because of their sandy nature

•      These are poor in soil fertility status, especially N,P,K,S and Zn, because of the sand cover, rich in quartz and poor biological activity.

•      Weatherable minerals like Feldspars although present, donot weather because of the limiting rainfall.

Classification

         In the Genetic System, they are classified as Pedocals, Sierozems, Calcareous Sierozems or Desert soils, belonging to the order: Zonal soils. Sand dunes of the arid region are classified as Regosols within the order Azonal. They belong to the orders: Aridisols and Entisols.

Land Use

         These soils are fertile and are comparable with the Alluvial soils, except for aridity, that restricts their use for raising crops because of water constraint. Due to aeolian action, the dry sand move in the direction of the wind and poses a threat to the adjacent cultivated areas by depositing a thick mantle of sand at the surface. Sandy texture has poor water and nutrient holding capacity and excessive infiltration and leaching or drainage. Sink –holes is a problem in gypsic horizon.

         These soils are inherently fertile because of weatherable minerals but because of aridity, the chemical weathering is limited to release cations. Once irrigated, these soils have the potential to grow two crops in a year.  These soils can be profitably used for growing one to two crops in a year if irrigation is made available.