Recover of Soil Microbial Community Functions in Beech and Turkey Oak Forests After Coppicing Interventions

Abstract

Forest management influences the occurrence of tree species, the organic matter input to the soil decomposer system, and hence, it can alter soil microbial community and key ecosystem functions it performs. In this study, we compared the potential effect of different forest management, coppice and high forest, on soil microbial functional diversity, enzyme activities and chemical-physical soil properties in two forests, turkey oak and beech, during summer and autumn. We hypothesized that coppicing influences soil microbial functional diversity with an overall decrease. Contrary to our hypothesis, in summer, the functional diversity of soil microbial community was higher in both coppice forests, suggesting a resilience response of the microbial communities in the soil after tree cutting, which occurred 15-20 years ago. In beech forest under coppice management, a higher content of soil organic matter (but also of soil recalcitrant and stable organic carbon) compared to high forest can explain the higher soil microbial functional diversity and metabolic activity. In turkey oak forest, although differences in functional diversity of soil microbial community between management were observed, for the other investigated parameters, the differences were mainly linked to seasonality. The findings highlight that the soil organic matter preservation depends on the type of forest, but the soil microbial community was able to recover after about 15 years from coppice intervention in both forest ecosystems. Thus, the type of management implemented in these forest ecosystems, not negatively affecting soil organic matter pool, preserving microbial community and potentially soil ecological functions, is sustainable in a scenario of climate change.

Keywords: Coppice and high forest; Enzyme activities; Microbial functional diversity; Soil organic C.

Fig. 1

Biplots of principal component analyses (PCA) with A the superimposition of the confidence ellipses showing the differentiation between the interaction forest management and season factors in soil under beech. The plots display the first (PC1) and second (PC2) principal components, variance explained by PC1 and PC2, and B the variable contributions to the first two principal components. HA = high forest autumn; CA, coppice autumn; HS, high forest summer; CS, coppice summer

Fig. 2

Biplots of principal component analyses (PCA) with A the superimposition of the confidence ellipses showing the differentiation between forest management in soil under turkey oak. The plots display the first (PC1) and second (PC2) principal components, the variance explained by PC1 and PC2, and B the variable contributions to the first two principal components. H, high forest; C, coppice

Fig. 3

Biplots of principal component analyses (PCA) with A the superimposition of the confidence ellipses showing the differentiation between seasons in soil under turkey oak. The plots display the first (PC1) and second (PC2) principal components, variance explained by PC1 and PC2, and B the variable contributions to the first two principal components

Fig. 4

FDA activity (mean ± s.e.) (upper panel) in soil of A beech and B turkey oak and arylsulfatase activity (mean ± s.e.) (lower panel) in soil of C beech and D turkey oak under different forest management, sampled in two seasons. H, high forest; C, coppice; A, autumn; S, summer. Different letters indicate significant differences between forest management

Fig. 5

Heat map of the metabolic profile of microorganisms based on the consumption of various C sources after 192 h of incubation (EcoPlate method) in soils of beech forest under different forest management, sampled in two seasons. In the heat map analysis, the AWCD scores (absorbance of the carbon substrate − absorbance of the control well)/number of carbon substrates are shown. The highest consumption (i.e. higher AWCD) can be identified by a red colour and the lowest consumption (i.e. lower AWCD) by a blue colour. H, high forest; C, coppice; A, autumn; S, summer

Fig. 6

Heat map of the metabolic profile of microorganisms based on the consumption of various C sources after 192 h of incubation (EcoPlate method) in soils of turkey oak forest under different forest management, sampled in two seasons. In the heat map analysis, the AWCD scores (absorbance of the carbon substrate − absorbance of the control well)/number of carbon substrates are shown. The highest consumption (i.e. higher AWCD) can be identified by a red colour and the lowest consumption (i.e. lower AWCD) by a blue colour. H, high forest; C, coppice; A, autumn; S, summer

Fig. 7

Biolog-AWCD values of microbial communities calculated during a 192-h incubation in soils of beech forest under different forest management, sampled in two seasons: A summer and B autumn. Asterisks indicate significant differences between forest management

Fig. 8

Biolog-AWCD values of microbial communities calculated during a 192-h incubation in soil of turkey oak forest under different forest management, sampled in two seasons: A summer and B autumn. Asterisks indicate significant differences between forest management