1. Urban Ecosystem Accounts
Emily Connors
Office for National Statistics

2. Why urban areas are so important Defining urban Ecosystem services
Contents
Why urban areas are so important
Defining urban
Ecosystem services
Hedonic Pricing Method

3. Why urban areas are so important
UN 2014
54%
Of the world’s population lives in a town or city
82%
Of the UK population live in urban areas
ONS 2017
5,900
Life years saved in UK urban environments from nature
What are we trying to achieve?
Produce an urban ecosystem account to help private and public sectors value and monitor the extent and condition of nature in the urban environment
Help policy makers prioritise investment and make informed decisions.
Text for Introduction
The bigger picture- Currently ONS is in the process of creating 8 broad habitat natural capital accounts identified in the These are aimed to be completed by 2020 (this will already have been mentioned by Colin so can just be quickly mentioned.
What are we trying to achieve?- The purpose of this study is to produce an urban ecosystem account which aims to help both private and public sectors to value and monitor the extent and condition of nature in the urban environment, in addition to helping policy makers prioritise investment and make informed decisions. The urban accounts will offer a coherent way of looking at the value of green space in urban areas within the UK and raise awareness of their social and economic significance.
Why are the urban accounts specifically significant?- As urban areas are where the majority of the population resides and green space is very limited in extent, it can be argued that the services that urban natural capital provides is more valuable than that of other broad habitats and the accounts are one of the more policy relevant.

4. Defining urban Land cover or population? How we define urban.
The ONS (2011) Rural-Urban Classification defines output areas as urban if they have a population over 10,000. The land cover map however, as the name suggests, defines what’s urban on land cover.
How we define urban.
Data Source: ONS (2011) Built-up-Areas dataset
Limitation: Excludes large areas of natural capital surrounded by urban land such as large parks or rivers
Modification: Introduce a buffer zone around the built up area map
Urbanisation - The world is becoming increasingly more urbanised. The UN (2014) around 54% of the world’s population now lives in either a town or city and the Mapping and Assessment of Ecosystems and their Services (MAES 2016) technical report stated that almost 3 out of 4 citizens in the European Union live in what is classed as an urban area. In context of the UK, 82.3% of people lived in urban areas and 17.7% lived in rural areas in 2011 (UN, 2014).
How is urban defined? – Most sources define urban either based on population or on land cover. For example, the ONS (2011) Rural-Urban Classification defines output areas as urban if they have a population over 10,000. The land cover map however, as the name suggests, defines what’s urban on land cover. The urban class includes city and town centres where there is little or no vegetation. It also includes industrial areas such as dock sides, car parks, and industrial estates.
How we define urban in our accounts - We follow Eftec (2017) in their selection of the ONS (2011) Built-up-Areas dataset on the basis that (i) it captures all built-up-areas and therefore all areas that will not be included in other broad habitat accounts (this is not the case for Rural Urban Classification 2011 (RUC2011), Major Towns and Cities) (ii) other urban classifications (e.g. major towns and cities) can be looked at within this dataset (iii) it is based on physical settlement morphology and not statistical units (i.e. Output Areas that RUC2011 uses) which will extend into rural areas.

5. Buffer width = 0.012 * √Polygon area
Modification - buffer
Apply a variable sized buffer to each polygon which also draws in any areas enclosed to capture large parks in cities.
Variable buffer which is a function of the size of the polygon used
Buffer width = * √Polygon area
ONS Built-Up-Area
Area (ha)
Buffer width (metres)
Eardington 20 5
Bristol
14,443
144
Sheffield
16,748
155
Nottingham
17,636
159
Liverpool
19,961
170
Greater Manchester
63,025
301
Greater London
173,785
500

6. It is a cross cutting habitat account Extent account (enhanced BUA (2011))
Discuss how the enhanced urban boundary captures the entire LCM definition of urban in addition to other broad habitats defined by the UKNEA. If we were to of used the LCM definition of urban for the project we would of missed areas of greenery that are beneficial to urban inhabitants
1,212,000 ha

7. Extent account (enhanced BUA (2011))
Indicator
Amount
Source
Scale
Total urban area
1,765,700 ha
Enhanced ONS BUA (2011) UK
Mountains, moors and heaths
11,200 ha
LCM2007;
Green infrastructure features
Park area
420,400 ha
OS Mastermap GB
Trees
99,400
Allotments
163,000
National Society of Allotment and Leisure Gardeners
Blue infrastructure features
Lakes/Ponds/ Riversb
22,700 ha

8. Regulating Cultural Ecosystem services Provisioning Air filtration
Food
Fibre
Water
Fuel/energy
Regulating
Air filtration
Water filtration
Protection against noise, small and visual pollution
Flood, erosion and landslide protection
Temperature regulation
Pollination and seed dispersal
Cultural
Recreational enjoyment
Scientific and educational interactions
Heritage and aesthetic interactions
Symbolism
Existence

9. Ecosystem services – new services developing
Provisioning
Food
Fibre
Water
Fuel/energy
Regulating
Air filtration
Water filtration
Protection against noise, small and visual pollution
Flood, erosion and landslide protection
Temperature regulation
Pollination and seed dispersal
Cultural
Recreational enjoyment
Scientific and educational interactions
Heritage and aesthetic interactions
Symbolism
Existence

10. Hedonic pricing method to value cultural services
What is the hedonic price method?
Products can be broken down in to a number of characteristics.
How can we use it?
Use house price data to estimate the extent to which the green and blue space affect price
What are we trying to value?
A bundle of ecosystem services which are ‘paid for’ when purchasing a house e.g. access to a park or aesthetic views
Recreational enjoyment
Scientific and educational interactions
Heritage and aesthetic interactions
The hedonic pricing method is based on the premise that a class of differentiated products can be broken down in to a number of characteristics. A combination of these characteristics and the external factors that affect the product is what is deemed to then determine the price. The most common example of this is property values, where the market price of a property is determined by a combination of structural characteristics (floor area, number of bedrooms, garden, garage etc.) and the socio-economic and environmental characteristics of the surrounding area (quality of schools, access to retail, levels of water/air pollution, proximity to green space etc.)
The hedonic pricing method can be used to estimate the extent to which the characteristics/ factors affect the price through running a regression of house prices on explanatory variables (the structural and socio-economic/ environmental characteristics). Working on the assumption that nature is implicit in property prices, this methodology can therefore be used to extract values for environmental goods/services from market-based transactions.
Rationale – “We have already attempted to estimate the value of cultural services natural capital provides in a variety of ways (Ricardo and their recreation valuation, Eftec on public health values) but we also know that there is a lot of value embedded in property prices (Mention previous studies such as Gibbons et al. here and some of their main findings). Also mention the Ricardo study and how it was unable to pick up the value of “free trips” as there was no expenditure, and how the hedonic method may be able to pick up some of this value in the form of recreational opportunity.
Symbolism
Existence

11. Advantages/ Disadvantages
Estimates value based on real life choices rather than hypothetical ones (desirable from a policy perspective).
Data on property transactions and characteristics are readily available.
Fills a known gap in current recreation estimates – Free trips
Disadvantages:
For accurate and robust estimates to be obtained from the method, large datasets are required
Results depend heavily on the model specification that’s used
Represents a bundle of services e.g. amenity, health, views and therefore there’s an obvious risk of double counting.

12. In January we will publish….
Initial urban ecosystem accounts:
Extent account
Partial condition account
Partial ecosystem service account
Annual updates will then be made each year in our broad habitat ecosystem accounts - also include woodland, farmland and freshwater
Highlight again what is included in all the different accounts both physical and monetary.
Highlight the fact that this is not a time series so it’s all stock not flow.
Explain how the hedonic/ eftec work may be enhanced in future iterations.