Urban areas cover just 2.8% of the Earth's land area, but over 50% of the human population lives in them, and these proportions are growing rapidly. Such heavy concentration of people has a wide variety of important consequences. Those for their relations with the environment have attracted much recent attention from the media, pressure groups, policy makers, researchers, and local and national government. Of particular concern have been how improvements can most effectively be made to the environmental conditions experienced in urban areas, to the levels of interaction between urban dwellers and the natural environment, and to the contribution of urban areas to the broader scale provision of ecosystem services. This raises the key issue of the form of relationships between biodiversity and ecosystem services in urban areas, how the structure of urban areas (the spatial structure of the different kinds and extents of impermeable and permeable surfaces; urban form) influences these relationships, and thus how the existing structure can best be managed and how future structure can be planned to best effect. Although understanding of the levels and distributions both of biodiversity and of ecosystem services in urban areas has improved dramatically in recent years the relationships between biodiversity and ecosystem services have been extremely poorly studied in urban areas (and are largely absent from major collations of empirical studies). Indeed, these environments pose significant and unusual challenges: - the urban landscape is highly fragmented, with large portions sealed by buildings and paving; - greenspaces are embedded in a complex mosaic of buildings and roads that imposes major constraints and directionality on the flows of biodiversity and ecosystem service delivery across the urban landscape; - the intensity of human management of these environments can give rise to spatial patterns and scales of flows of energy, materials and biodiversity on which ecosystem services depend that would not naturally occur; and, - the very aggregations of people that give rise to urban areas typically necessitate less conventional approaches to conducting ecological research therein, involving greater engagement with the general public, and less dependence on the use of large pieces of equipment, which is "out of bounds" to the general population. In order to determine these biodiversity-ecosystem service relationships, develop deeper understanding and to test this understanding our overall approach to this project involves five main steps. We shall: - characterise the spatial ecological structure of urban areas; - determine biodiversity-ecosystem service relationships and the influence of connectivity on them; - determine the flows of biodiversity, and service delivery in selected cases; - experimentally perturb those flows to determine the impact on ecosystem service delivery; and - integrate these findings in the form of spatially explicit models which will form the basis of an "ecosystem service" layer for GIS models. This will enable us to deepen understanding, and to provide illustrations for stakeholders (such as planners, local people and NGOs) as to how "scenarios" of different development proposals might be tested, to provide support for decisions based on sound science and stakeholder engagement.

In recent years environmental and social scientists working with economists have begun to understand the value that nature provides to society. These 'ecosystem services' (ES) include things like the provisioning of food and fuel, regulating water quality and quantity, reducing pollution, storing carbon and producing landscapes and features of cultural and aesthetic significance. Using a range of widely agreed methods it has been possible to put economic values on these services and the stock of ES is referred to as 'natural capital'. These ideas have allowed nature to be included in the way that organisations and societies plan and make decisions. Economic development, for example, that erodes natural capital might be considered undesirable, especially if the loss of natural capital outweighs the benefit of the development. Another term, 'green infrastructure' (GI) is used to describe the natural or semi-natural features such as hedgerows, parkland and street trees that make up part of human landscapes. GI can provide ecosystem services and therefore adds to natural capital. Urban trees, for example, regulate water flow, take in carbon dioxide, can reduce air pollution and have cultural significance. Although these ideas are well developed in theory, applying them in practice has proved more challenging because the data required to calculate ES valuations are not widely available and the methods used are complex. This is a barrier to governments and businesses understanding and using these important ideas in their planning and decision making, and more so for individual citizens, small organisations or community groups who might be interested in the real value of their environment. The VITAL project is made up of environmental scientists from the Open University with experience of running large citizen science projects, specialists in ES and trees from Forest Research, and Treeconomics a social enterprise which has been instrumental in engaging organisations in valuing their trees. We aim to develop a system that allows anyone from individual citizens to local authorities, businesses and large organisations to value the trees around them. We will significantly improve an existing OU citizen science tool: 'Treezilla' which allows users to map and gives ES valuations of trees, so that it links with the most widely used professional system for ES tree valuation: i-Tree Eco. These improvements will give all users access to powerful tools for valuing trees. We will engineer these systems such that data from one feeds into the other, and as more data are collected in Treezilla, it is used to refine the system further. The value of our tools will be in their use by large numbers of people and organisations, so we have partnered with key organisations with interests in the value of trees in their environment to deliver the project. We will work closely with the Parks Trust Milton Keynes who are responsible for GI in one of Britain's most wooded cities, to understand how organisations can use Treezilla, using what we learn to improve training and promotion of Treezilla to other users. We will then work closely with a major governmental organisation: Natural Resources Wales to deliver specific projects demonstrating the use of Treezilla to that organisation and others like it. Through a third partnership, with The Tree Council, which has tens of members made up of local authorities, community groups and small and large charities, and supports a national network of 8000 volunteer Tree Wardens, we will communicate our tools and what we have learned to a very large number of potential users. These, and all users of Treezilla, will have free and open access to tools for valuing trees and the same access to a massive and growing dataset of trees and tree valuations from across the UK.

The UK has an exciting opportunity to radically improve the urban environment through the government's commitment to the creation of more "green infrastructure" (GI) in our town and cities. It is recognised that urban GI delivers multiple benefits to nature and society, by increasing biodiversity, enhancing those ecosystem services (such as air quality improvement, removing carbon dioxide from the air, and reducing flood risk) and improving the health and wellbeing of urban residents by living and working in a biodiverse rich environment. This extends to the role that rivers, streams, canals and other water bodies also play - the "blue" infrastructure and both are heavily constrained by the built, "grey" infrastructure. Urban GI exists as a patchwork of fragments of varying size, shape and composition within intensely complex and fragmented landscapes. This makes the identification of key biological processes linking urban landscapes to multiple ecological functions very difficult. Connectivity between green fragments can have much larger effects on the relationship between ecological structure and functioning than simple patch sizes. There is thus a need to understand how patches and their connectivity alter biological communities and ecological functioning. A key challenge faced by planners when investing in Green and Blue Infrastructure is how this should be designed and configured, so that the interactions between the green-blue-grey infrastructures will most effectively deliver multiple benefits. We shall be working closely with the general public, local authorities, NGOs and local businesses as Project Partners throughout the lifetime of the project. Improved understanding of multiple benefits from greenspace (improved air quality and health outcomes, biodiversity, carbon storage, etc.) can help stimulate engagement with, and uptake of GI solutions at a local scale, by "co-designing" such interventions. The project will have six work packages: WP1 Site selection and spatial survey: determining the relationship between urban spatial configuration, air quality and soil moisture, and the influence on these of biodiversity and local meteorology using sites in Luton, Bedford and Milton Keynes. WP2 Urban Observatory GI manipulations: real world and controlled experiments to investigate the impact of interventions on air quality, water and biodiversity. WP3 Mechanistic Modelling of urban ecological networks: better understanding how urban fragmentation and structure influence: i) air purification services; and ii) cascading effects of urban structure, air pollution and water availability on urban trophic networks. WP4 Integrated Modelling to assess the effects of altered greenspace structure and management: development of Bayesian hierarchical models to (i) allow 'virtual' scenarios to assess to the effects of altered GI on air quality, water regulation and biodiversity; and (ii) provide information for inputs to other WPs. WP5 Barriers to effective GI interventions: understanding the barriers to successful implementation of GI and identifying enabling mechanisms. WP 6 Impact: engagement with key users and stakeholder groups to understand their requirements and so that new knowledge is transferred to critical decision makers. This project aims to deliver new knowledge on how urban form affects biodiversity, biological processes and ecosystem services derived from them. This information can be used to design healthier and more resilient urban environments through targeted interventions with green, blue, and grey infrastructures, while improving our understanding of current barriers to implementation. The work will focus on the interventions that improve air quality, enhance water management, and safeguard and enhance biodiversity.