Native trees for improved UK upland soils and less flooding downstream?

With increases in precipitation and over-compacted soils in many UK upland areas causing elevated flood risk downstream, it is thought woodland expansion and native tree planting could offer an effective ‘Nature-based Solution’ (NbS) to the climate emergency. 

This nature based approach works on the principle that we can use natural processes to provide ‘natural flood management’ (NFM) instead of relying on costly and sometimes ineffective hard engineering approaches. There has been much debate in recent years if planting of trees might be necessary in our upland catchments.

Some of these upland areas, particularly those where naturally freely draining soils have been over compacted by previous heavy grazing (typically on valley slopes and now characterised by species poor acid grassland) could benefit from more native trees.  As our research paper (Murphy et al., 2021) shows the establishment of native woodland could help these soils recover for improved flood mitigation within relatively short time periods. However context is everything and we need more works which helps us understand the mechanisms controlling the NFM benefit of woodland creation, and the amount of woodland within catchments needed to reduce river flows.

You can read a summary of our research at  – https://www.plymouth.ac.uk/news/new-woodlands-can-help-reduce-flooding-risk-within-15-years

The full paper (Murphy et al., 2021) is available via – https://doi.org/10.1002/ldr.3762