Indigenous trees restore soil microbial biomass at faster rates than exotic species

Background and aims Microbial community characterization is used as a disturbance indicator for soils. However, there is little evidence on the response of soil microbes to restoration. We aim to study the effects of restoration, using different trees, on soil communities and document temporal changes. Methods On a phosphate mine in Yunnan Province, China we selected sites with different restoration ages (2, 23, and 30 years) and tree species ( Eucalyptus globulus (exotic), Cupressus torulosa , Pinus yunnanensis (both indigenous)). Control sites included natural land, and disturbed sites without vegetation. Soil microbial communities were characterized using Phospholipid-derived fatty acids analysis. Soil nutrients concentrations were analysed. Results Compared to control sites, disturbed soils exhibited significantly lower microbial diversity, bacterial biomass, soil organic carbon and nutrient concentrations. Recultivation with trees restored the soil microbial communities to a state similar to natural soils. Indigenous trees increased soil N concentration, and microbial biomass at a faster rate than the exotic Eucalyptus trees. Soil microbial diversity increased with plantation age. Conclusion Soil communities can be used as soil health indicators in restoration monitoring. Additionally, soil microbial communities recovered fastest under indigenous compared to exotic trees, which further underlines the importance of tree species selection in restoration management.