Defragmenting the fragmented urban landscape (DEFRAG)

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.