Developing Criteria for an Emerging Land Use - Sphagnum Moss Harvesting - Through Stakeholder Engagement and Consequent Potential Sphagnum Harvesting Area in Finland.

Abstract

Sphagnum mosses are a dominant plant group in boreal and temperate peatlands, significantly contributing to peat accumulation and, consequently, terrestrial carbon stock. Sphagnum moss as a potentially renewable alternative for peat is an emerging raw material in the horticultural growing medium industry - hence Sphagnum is harvested or farmed in multiple countries worldwide. In Finland, Sphagnum harvesting is a new land use of peatlands, currently conducted on a small scale, preferentially on sites previously affected by other types of land use. However, with ample suitable harvesting areas available, such as forestry drained peatlands with low timber production, Sphagnum harvesting has the potential to become a significant land use practice. To assess the available Sphagnum harvesting land resources in Finland, we employed collaborative working methods, including repeated workshops with stakeholders and semi-structured interviews to establish criteria for site selection. Through stakeholder engagement, the criteria were selected, further modified, and used in spatial analysis to delineate potential harvesting areas and estimate land area. The criteria formulation involved several stages, including identifying existing land-use restrictions and other possible constraints on peatlands, and assessing where suitable Sphagnum yield and production costs can be achieved. The resulting area estimate ─ 241,000 hectares of potential Sphagnum harvesting area ─ is substantial, accounting for up to 3% of all peatland areas in Finland. It also exceeds the estimated area needed for Sphagnum harvesting to replace peat as a growing medium in Finland. The stakeholder engagement process revealed the need for further regulation of Sphagnum harvesting if the activity is upscaled.