The key objective of peatland rehabilitation is environmental stabilisation. This involves stabilising the bare peat surfaces, slowing water movement across the bog and trapping mobile silt.
Enhanced rehabilitation measures will deliver more substantial ecosystem service benefits and will bring accelerated and enhanced environmental stabilisation. The objective of these enhanced rehabilitation actions is to optimise suitable baseline hydrological conditions for climate action benefits, to slow the movement of water across these landscapes and to accelerate environmental stabilisation via natural colonisation. This means re-wetting peat with the most optimum water levels (generally at or slightly above the surface of the peat) for the development of vegetation that suits the underlying environmental conditions, setting these areas on a trajectory towards naturally functioning wetland and peatland habitats.
Enhanced Rehabilitation Measures
Enhanced rehabilitation measures include blocking production field drains with peat drain blocks alongside more intensive measures such as the creation of low bunds to hold water, re-profiling of peat fields to create more suitable flatter topography to maintain optimal hydrological conditions and potentially seeding or introducing natural vegetation. These measures will allow for a more uniform coverage of water at an ideal depth (c.100mm +_50mm) for vegetation colonisation and in particular the development of mosses.
Different rehabilitation methodologies will be applied due to different cutaway environments and underlying ground conditions (dry cutaway, wetland cutaway, deep peat cutaway). In general, there is ‘no one size fits all’ as each cutaway bog will have different rehabilitation challenges. The over-arching and guiding principle for the enhanced rehabilitation measures will be to ‘do the right thing in the right place’ (integrating the most suitable objectives, actions (interventions) and targets with heterogenous environments and differing environmental conditions between cutaway bogs) so as to optimise ecosystem service benefits.
Measures to seek to improve environmental conditions through re wetting will be guided by site specific data collection and will take account of the current baseline conditions and site variability. The measures will target those areas where maximum climate action and other benefits can be developed and where embryonic peat-forming habitats could potentially be developed. For example, deeper peat cutover bog sites have potential to develop embryonic, Sphagnum-rich peat-forming habitat, while shallower peat sites may develop to fen type habitats.
Hydrological modelling will be carried out as part of the design process to ensure the intended areas are re-wetted and there is no unintended flooding in adjacent lands.
Monitoring shall be carried out to determine that objectives have been reached. Examples of these objectives include reduction in bare peat cover and establishment of suitable habitats including Sphagnum-rich vegetation, creation of suitable hydrological conditions, reduction in greenhouse gas emissions, reduction in fluvial carbon emissions and improvements in water quality.