Getting restoration right, for peat's sake!

Simon Theilen (based in our Perth office) assesses an eroded peatland

Where there is categorisation, it is based on the extent of visible bare peat. Predicted emissions (and emissions reductions) are tied to this categorisation but the more pertinent issue with degraded peatland is that when the water table is lowered (through man-made drainage, or erosion), the peat within the wider peat mass is then exposed to oxygen, oxidisation and conversion to CO2. So, does the distinction between bare peat and water table matter?

The industry has developed techniques based upon reducing bare peat, as this was the categorisation goal, but it has not specifically built techniques to raise water tables. However, a recent Defra report attempts to tie peatland emissions to water table levels – this is more scientifically robust and a good direction of travel.

Techniques for ‘restoring’ artificial drainage and minor erosion is likely to have a very good and robust outcome in terms of water table levels. Conversely, techniques for moderate to severe erosion is likely to have a very poor outcome in terms of water table levels. Much of this comes down to the risk and difficulty of intervening in these severe circumstances.

Even if the industry is not mandated to pivot to these more focussed efforts soon, by either Peatland Action (Scottish Government grant funding) or Peatland Code (carbon credits), it is likely that this is the direction of travel regardless of regulatory obligation. If we are committed to peatland restoration then we should be doing it as effectively as we can to get proper, lasting results.

The industry needs to adopt these informed perspectives eventually and new techniques need to be developed that are geared more to positively affecting water table levels. Current techniques that are unlikely to achieve any effect need to be reviewed and possibly discarded in some circumstances.

And, potentially, areas in which we do not currently have satisfactory techniques should be left – either because they are not cost effective, they are too risky, too premature, or because we would do more harm than good.