Soils : Importance and Relevance in UPSC Prelims

Since past few years the number of questions from Geography has increased substantially. About 12-13 questions have been asked from this section in UPSC Prelims as is evident from the Previous Year Papers of UPSC Prelims. There are various subsections that are more or less frequent and are often targeted upon. The Physiographic Regions Of World and India, the resources and minerals of world and India are of huge importance. The soil is another subsection that has huge importance for prelims questions. The soil formation, soil profile, the different types of soils and regions under different soils are the areas from where the maximum number of questions asked. The types of crops that are grown in these soils are also significant in this regard. In this article we will discuss how to approach the soils in Geography and what resources are needed to be followed to solve questions based on soil.

Before moving to discussion of strategy and resources lets have a look at the definition of soil. Soil can be simply defined as a mixture of small rock particles/debris and organic materials/ humus which develop on the earth surface and support growth of plants. However this definition is not the only definition there are several other definitions too but the point is to develop a basic understanding of the soil. There are various components of soil based on which soil has been categorized in to number of soils. A soil profile is a vertical cross-section of the soil, made of layers running parallel to the surface. These layers are known as soil horizons. The layers of soil can easily be identified by the soil colour and size of soil particles. The different layers of soil are:

• Topsoil
• Subsoil
• Parent rock

Each layer of soil has distinct characteristics.

Soil profile helps in determining the role of the soil as well. It helps one to differentiate the given sample of soil from other soil samples based on factors like its colour, texture, structure, and thickness, as well as its chemical composition. Based on the layers of the soil it has been devided into several categories such as alluvial soil, black soil, red soil, laterite soil, peat soil, mountainous soil etc. The different type of soil is distributed across different regions in the world. The soil characteristics is hugely impacted by the weather of a particular region.

Once the definition and structure of soil has been cleared lets have a look at resources and books which should be followed. The basic understanding can be cleared through the NCERT books. The previous year questions could be the best source to understand the pattern and types of question that are asked frequently in Prelims Exam. This could be supplemented by a good atlas where you could mark the location and agricultural crops grown under different types of soil. The questions on soil are often based on maps in which you are asked the different regions shown in the map. However the entire exercise could be cut short with the Prelims Sampoorna Fact File On Soils by GS Score which is a compilation of all the necessary information of the soil, its types, crops grown under the different soils and regions coming under the different types of soil. Further the information has been given in bullet form that is easy to encapsulate and comprehend from exam point of view.