soil, testing, analysis
In studying and characterizing the properties of different soils, many kinds of soil analyses are used. Chemical analyses are made to determine the amounts of each element or chemical compound and the chemical reactions which take place in soils. Analyses of the physical properties of soils give information about soil texture (the proportions of sand, silt and clay), soil structure (the degree of aggregation) and the movement of air and water in soils. The minerals are studied by mineralogical analyses. Microbiological analyses are used to study the kinds and numbers of different microorganisms and the processes carried on by these microorganisms in the soil. Simple soil analyses are called soil tests. The first step in soil testing is the collection of the samples in the field. Usuall.15 or more samples from a uniform area are collected and well mixed to provide one necessary sample. In the laboratory different tests are made for different component elements.
