Post-fire peatland recovery by peat moss inoculation depends on water table depth

Abstract

Peatland restoration is essential to preserve biodiversity and carbon stored in peat soils. Common restoration techniques such as rewetting do not always result in the full recovery of peatland taxonomic and functional properties, threatening the resilience of restored peatlands and their carbon stores. Here, we study the use of peat moss inoculation in stimulating the short-term taxonomic and functional recovery of a wildfire-impacted peatland using mesocosms at high and low water table depth, representing ideal and adverse hydrological conditions respectively. Inoculation in conjunction with high water tables accelerated the recovery of the vascular plant and prokaryote communities. Importantly, Sphagnum—the keystone genus in these peatlands—only established in inoculated mesocosms. Together, this resulted in an increased CO2 uptake by approximately 17 g m−2 day−1 and reduced overall nutrient content in the peat pore water. Synthesis and applications. Our results indicate that inoculation can be used to accelerate the establishment of peatland-specific species. In addition, they suggest the potential to combine peat moss inoculation and hydrological restoration to accelerate the uptake of carbon back into the system post-fire. This offers a basis for future work exploring the long-term use of inoculation to return disturbed peatlands to their pre-degraded state, and a wider application of soil inoculation as a mechanism for functional recovery.