The rate of succession is much faster in secondary succession as the substratum (soil) is already present as compared to primary succession where the process starts from a bare area (rock).
A primary key is a field that identifies each record in a database table admitting that the primary key must contain its UNIQUE values.
A secondary key shows the secondary value...
Primary treatment involves the removal of large sized floating and suspended solids by physical methods, while secondary treatment involves decomposition of organic matter by microbial action.
