As part of the ongoing Leeds4Trees collaboration between LEAF, the United Bank of Carbon and Leeds City Council, we have been exploring a number of natural capital valuation methods. Balancing the planting and management of urban trees with development is a continual challenge for local authorities. Natural capital valuation tools can help us to better understand the importance of trees as assets in the urban environment to inform decision making.
In our new research, we have taken a focus on Middleton Park, a ward within the unitary authority of Leeds. The study demonstrates how a range of natural capital valuation tools can be used to estimate the environmental benefits provided by the trees in Middleton. This forms the second stage of our Leeds-wide project (Read more about stage one here.).
The methods used in this research are
- i-Tree Eco – to estimate the number of trees, gain an understanding of the health and structure of the trees and estimate their environmental benefits.
- Capital Asset Valuation for Amenity Trees (CAVAT) – to make an assessment of the amenity value of the trees.
- Bluesky National Tree Map data – to estimate the number of trees in Middleton.
- i-Tree Canopy – to estimate the total canopy cover of the city of Leeds, and individual wards.
We carried out a plot-based survey of the trees in the Middleton Park ward, which we used for our i-Tree Eco analysis and CAVAT assessment. With 43 randomly located survey plots (of 11.2 metre radius) across the 928 hectares of Middleton Park, we surveyed 144 trees with the support of fantastic volunteers from the local community.
The natural capital valuation of the trees in Middleton has demonstrated the importance of maintaining healthy, mature trees and planting more to enhance the delivery of ecosystem services. By maintaining existing canopy cover whilst engaging in woodland creation plans for Leeds, the benefits outlined in our research will be enhanced across the city.
To read about the project, our results and for references, you can access the report here: Mooney, H., Walker, H., Gugan, A. and Scott, C. 2020. The Trees of Middleton: a case study of natural capital valuation in Middleton Park Ward, Leeds. Leeds: United Bank of Carbon and University of Leeds.