Microbial diversity and enzymatic activity of soils in coniferous forest ecosystems

Boyka Malcheva

Abstract: Microbial diversity and enzymatic activity of brown forest soils (Distric-Eutric Cambisols, FAO) under spruce (Picea abies L.) and white pine (Pinus sylvestris L.) from the region of the Western Rhodopes were studied. Main role in the initial stages of decomposition of organic matter in the studied forest soils is played by non-spore-forming bacteria, followed by bacilli. Actinomycetes and micromycetes, which are more actively involved in the final stages of organic degradation, are less represented. A directly proportional relationship is established between the amount of bacteria that absorb mineral nitrogen and the content of total nitrogen in the soil. The values of enzymes cellulase and catalase correlate with the total amount of microorganisms. Total microflora and enzyme activities are higher in the soils under spruce than in the soils under white pine. The effect of soils fertilization after a long period of time is considered as an indirect factor for microbiological and enzymatic activity, through better development of tree species and more complete structuring of the microbiocenosis. In these soils, biogenicity and enzyme activities have higher values compared to control, non-fertilized soils. The share of actinomycetes in the composition of total microflora in soils indirectly affected by fertilization increases, compared to the controls, which shows that the microbiocenosis is in a more final stage of formation in these soils.

Keywords: coniferous ecosystems; enzymes; forest soils; microorganisms

Date published: 2020-10-02