Microbial controls on carbon fluxes in forest-to-bog restoration

Abstract

Northern temperate peatlands are globally efficient terrestrial carbon stores subject to large-scale afforestation in the 20th century. Afforestation of open peatland compromises their ability to function as a net sink of atmospheric carbon dioxide (CO₂) and may become sources of CO₂ and other greenhouse gases (GHGs). Microorganisms control GHG fluxes through both direct (e.g. decomposition) and indirect (e.g. predation) and some are responsible for the fixation of atmospheric carbon.

Forest-to-bog restoration aims to recover key ecosystem functions, however, there is little evidence to show whether restoration can recover microbial community structure and the carbon balance. Key knowledge gaps exist calling for further investigation from a range of different restoration techniques, sites and peatland types. This study provides empirical evidence on the balance between carbon uptake through photosynthesis and soil respiration, because this will essentially determine the C sink potential and inform policy and future management of these ecosystems.

This project is highly applied, contributes novel data on the important role of microorganisms in forest-to-bog restoration and presents an annual gaseous C budget over a chronosequence of forest-to-bog restoration areas. This study is the first to highlight the potential of testate amoeba communities and functional traits as bioindicators of the progress of forest-to-bog restoration in both blanket and raised bog. Using a space for time substitution approach, findings here suggest forest-to-bog restoration can be beneficial for the carbon balance over timescales of around ten to fifteen years.

These data add to the limited existing evidence base on the carbon balance for UK peatland undergoing forest-to-bog management and are the first such evidence for raised bog in the UK. In addition, this study further demonstrates how published soil respiration models can be improved by accounting for plant function and provides the first evidence of the potential links between testate amoebae and in-situ GHG fluxes from forest-to-bog sites.

Date of Award	29 Jun 2020
Original language	English
Awarding Institution	Edge Hill University
Supervisor	JAMES ROWSON (Director of Studies) & CLAIRE JONES (Supervisor)