Enviro - Study

Physical properties of soils can be described under the following heads   (1) Soil separates and texture (2) Structure of soil (3) Weight and soil density (4) Porosity of soil (5) Permeability of soil (6) Soil colour (7) Temperature of soil, and (8) Soil Plasticity, Compressibility and Erodibility 1. Soil Separates and Soil Textures Mineral fraction of soil consists of particles of various sizes. According to their size, soil particles are grouped into the following types (Table 23.1). The particle sizes of above groups are suggested by International Society of Soil Science. In India, international system of particle differentiation is commonly followed. The particle types are generally called ‘soil separates’ or ‘soil fractions’.  Amount of soil separates is determined by a process known as mechanical analysis. In this process, soil sample is crushed and screened through a 2 mm round hole sieve. The screened soil is then homogeneously dispersed in water and allowed to settle....

  Soil Structure: Definition, Types. After reading this article you will learn about Soil Structure:- 1.  Definition of Soil Structure  2.  Types of Soil  Structure  3.  Classes 4. Grades  Definition of Soil Structure The arrangement of soil particles and their aggregate into certain defined patterns is called structure. The primary soil particles "sand, silt, and clay" usually occur grouped together in the form of aggregates. Natural aggregates are called peds, whereas clod is an artificially formed soil mass. The structure is studied in the field under natural conditions and it is described under three categories: 1. Type  - Shape or form and arrangement pattern of peds. 2. Class - Size of peds. 3. Grade - Degree of distinctness of peds. Types of Soil  Structure There are four principal forms of soil structure (a) Plate-like: In this structural type of aggregates are arranged in relatively thin horizontal plates. The horizontal dimensi...