Problem 20
Page 887
Section 31.3: Critical Thinking Questions
Chapter 31: Soil and Plant Nutrition
Background and context
Soil forms the outermost loose layer that is present on the surface of Earth. Plants are dependent on soil for the supply of essential minerals. The quality of a soil is determined by its chemical composition, land features or topography, climate of the place, time, and the amount of organic matter present in it.
A typical soil has four important constituents: air and water, inorganic matter, organic matter, and living matter. The cultivation practices and the history of soil also affect the composition and fertility of soil.
Soil formation is a very complex and slow process. Many environmental. chemical, and biological processes lead to formation of soil. These processes continue for thousands of years and lead to formation of different layers of soil. Each layer of soil is different from the other layers.