Role of forested land for natural flood management in the UK: A review

• Published in: Wiley interdisciplinary reviews. Water Vol. 8; no. 5; pp. e1541 - n/a
• Main Authors: Cooper, Matt M. D., Patil, Sopan D., Nisbet, Thomas R., Thomas, Huw, Smith, Andrew R., McDonald, Morag A.
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.09.2021; Wiley Subscription Services, Inc
• Subjects: canopy modeling; Catchment area; catchment modeling; Climate change; Environmental impact; Environmental management; Flood control; Flood management; Floodplains; Floods; Hydrologic cycle; Hydrologic models; Hydrological cycle; hydrological modeling; Hydrology; interception loss; Moisture content; natural flood management; Peak floods; Plant cover; Policies; Risk; Water conservation; Water content; Watersheds; Woodlands; United Kingdom > UK
• ISSN: 2049-1948; 2049-1948
• DOI: 10.1002/wat2.1541

Natural flood management (NFM) is the use of natural processes and environments to mitigate flood risk by reducing and delaying peak flood. This review introduces the concept and history of NFM and looks at the current state of research into the potential for using different types of woodland to fulfill the aims of NFM. Four woodland types (catchment, cross‐slope, floodplain, and riparian) are discussed with reference to studies carried out, mainly in the United Kingdom, to determine the relative merits of each type and their effectiveness in mitigating flood risk. We then discuss how trees interact with the hydrological cycle, along with a discussion of modeling methods which seek to determine the amount of water intercepted by different types of forest cover. We find that while there is some evidence that carefully planned and managed woodland can mitigate flood risk, the published data for this evidence base is somewhat sparse. This may be either due to the long timescales needed for comprehensive studies or the relative infancy of the research on NFM. More research needs to be carried out in each of the four woodland types, especially in the UK, as policy makers are increasingly looking towards nature based solutions to mitigate the potential impacts of climate change. The concept of a combined canopy/hydrological model which can be scaled from stand to watershed level and incorporate different types of woodland is suggested as it would be beneficial in guiding woodland creation policy in the future, both at the local and regional scales. This article is categorized under: Science of Water > Water Extremes Water and Life > Conservation, Management, and Awareness Woodlands are known to have a positive effect on flood mitigation, but the impact of different woodland types for natural flood management is not fully understood. We review the current state of research and suggest that improvement is needed in quantifying the effect of woodland types on catchment streamflow.