Trees, soil chemistry and microbiota interactions: driving forces and feedback processes in a Mediterranean remediated ecosystem

Abstract

Trees are ecosystem engineers able to generate effects on soil properties and microbiota that could lead to a feedback effect (Aponte et al. 2013). We present here several evidences of interactions between different tree species with soil chemistry and microbiota, in the Guadiamar Green Corridor (SW Spain). 1) We have analysed the potential of seven tree species for phytoremediation of soils contaminated by trace elements. Some of the studied tree species showed a positive effect on soil phytoremediation: increase soil pH underneath the trees and high phytostabilisation of trace elements in the rhizosphere (Madejón et al. 2018). 2) Tree species identity was a driving factor for the activities of four soil enzymes involved in C, N and P cycles. For example, beta‐glucosidase activity tended to be higher in soils under white poplar (Populus alba) trees (Gil‐Martínez et al., in prep.). 3) Composition of soil fungal communities, determined by next generation sequencing (NGS) techniques, differed in relation to the tree species (Gil‐Martínez et al., in prep.). 4) Ectomycorrhizal fungal communities and their functional traits affected holm oak (Quercus ilex) performance in contrasted soil conditions. For example, As, Mn and Zn translocation from soil to roots was best explained by the composition of mycorrhizal fungal communities rather than by toxic elements concentrations (Gil‐Martínez et al. 2018). A synthesis of tree‐soil‐microbiota interactions in a Mediterranean remediated ecosystem is presented. References: Aponte et al. (2013) Forest Ecol & Manage 309: 36‐46. Gil‐Martínez et al. (2018) Front Plant Sci. 9:1682. Madejón et al. (2018) Catena 166: 34‐43.