Agriculture Reference
In-Depth Information
2.4.2.2
Seasonal variation
In some environments, monthly sampling conducted in several soil and vegetation types
has revealed clear patterns of variation, in the numbers, biomass and activity of bacteria.
For example, in the Swedish coniferous forest soil studied by Clarholm and Rosswall
(1980), bacterial biomass underwent a clear seasonal pattern of variation with a minimum
of 5 g dry wt
in June and a maximum in September, nearly 10 times higher (Figure
III.10). The seasonal variation observed in a Japanese grassland by Higashida and Takao
(1985) had a lesser amplitude; the maximum density occurred in August which was
