Soil

TABLE OF CONTENTS

Sr. No. | Topic |
A | Introduction |
B | Types of Soil |
C | Crops and Soil |
D | Conclusion |
E | Bibliography |

A. Introduction
Soil maybe defined as a thin layer of earth’s crust. It serves as a natural medium for growth of plants as they obtain nourishing substances from it. In fact, much of life on earth depends on soil as a direct or indirect source of food. Animals get nutrients from eating plants in the soil and soil serves as a home to organisms like seeds, spores, insects and worms.

Soil is formed when forces of nature such as temperature, rain, wind, waves, animals and plants act on rocks and break them into tiny pieces over a long period of time. Thus soils differ amongst themselves in some or all properties. Some soils are red and some black; some are deep and some are shallow; some are coarse-textured and some fine-textured.

Soil is made up of four parts: air, water, minerals, and organic material. Air and water provide nutrients to plants so they can make food for themselves. Organic matter, also known as humus, is made of plant and animal remains in various stages of decay. Minerals are the clay, sand, and silt particles. As the proportions of each of these parts vary from location to location, they form different types of soil which form a system for plant growth.

B. Types of Soil

Sand
Sandy soil has mostly has
  * mostly sand and no organic matter. It is the heaviest, and allows water and air to move easily through it.
  * A soil with sandy texture has difficulty in retaining water and thus nutrients are not made available to the plants growing in such a soil.

Clay
Clay soil has
  * mostly clay, a little organic matter
  * Clay is sticky when wet and hard and brick-like when dry.
  * A clayey soil is poorer in aeration (due to stagnation of water) thus debilitating the plant growth.

Loam
Soil that is
  * composed of sand, silt, and clay in relatively even concentration...