Pollution Removal by Vegetation

Overview
Description: 

Trees remove air pollution, and this has health benefits to society that can be valued. The quantity of pollution removed, and the health benefit, will vary due to tree cover, levels of pollution, population density, and other factors. This tool allows users to explore the change in value resulting from new woodland planting, or removal of existing woodland, and its ability to remove PM2.5 pollution. The tool is based on new modelling by the UK Centre for Ecology & Hydrology (UKCEH) and Economics for the environment consultancy (eftec).

Input: 

User specified data on woodland planting and/or removal, within any local authority in the UK.

Output: 
Maps
Quantitative data on ecosystem services
Tables / statistics / reports
Economic assessment
Scale: 
Local scale
Landscape scale
Regional scale
Multi-scale
Cost of the tool (and guidance): 
Open access (free)
Context: 
Woodland only, but could be configured for additional land cover types.
Resource requirement (software): 
Access to internet
Level of technical expertise required: 
Internet use skills
Types of ecosystem service included: 
Regulating
Habitat type (UK NEA habitats): 
Woodland
Urban
How does it work?: 

Three calculation steps underpin the tool: Calculating quantity of pollution removal and change in pollution concentrations; pollutant-health dose-response models and the economic valuation of health benefits. Firstly, the atmospheric chemistry transport model EMEP4UK calculated the quantity of pollution removal by all UK vegetation types, and the change in pollutant concentrations as a result. The model takes into account pollutant emissions, chemical interactions in the air, atmospheric transport, the weather and vegetation removal, on an hourly time-step. Pollutant – health dose-response models used the AlphaRiskPoll model developed by EMRC to link changes in PM2.5 concentrations to changes in health outcomes. Health benefits included are avoided cases of respiratory hospital admissions, cardiovascular hospital admissions, and life years lost (reduced life expectancy as a result of long-term exposure) associated with changes in the concentration of PM2.5. The economic value of health benefits is based on Defra guidelines, which use Willingness to Pay estimates. The tool presents the health benefit in terms of £ per hectare of woodland to facilitate adding this benefit to others provided by woodlands.