Physicochemical properties of soil include soil texture, water, air, inorganic chemicals, and organic matter. The biological factors of soil are soil flora and fauna. Mechanical composition (texture) of soil is determined on the basis of size of soil particles i.e. sand, silt and clay particles (Table 30.1). However, the ratio of soil particles governs the porosity (pore size of soil), [...]
The following points highlight the top four tests for the presence of coliforms in water. The tests are: 1. Sanitary Tests for Coliforms 2. The Most Probable Number of Coliforms 3. The Defined Substrate Test 4.IMViC Tests. Test # 1. Sanitary Tests for Coliforms: The original test for the presence of coliform in water is done by standard multiple tube [...]
Microorganisms which live in soil are algae, bacteria, actinomycetes, bacteriophages, protozoa, nematodes and fungi (Fig. 30.2). A brief description of soil microorganisms has been given below: 1. Soil Algae: Soil algae (both prokaryotes and eukaryotes) luxuriantly grow where adequate amount of moisture and light are present. They play a variety of roles in soil. One of the important role of [...]