How does urbanisation shape biodiversity? Integrating spatial and temporal dimensions

Urbanisation is one of the most pervasive forms of habitat change. More than half of the world’s human population now resides in urban areas, and urban land cover is projected to triple between 2000 and 2030. Land conversion to urban built environment poses a major threat not only to particular species, but also to biodiversity. However, anthropogenic land use varies considerably in time and space, making it a key challenge to account for both dimensions in our attempts to understand how biodiversity is affected by urbanisation. While biodiversity along urban-rural gradients has been the focus of a substantial body of work, this research is mostly geographically localised, neglecting larger scale effects that would help generalise these findings. Even more surprisingly, very little is known about temporal changes biodiversity in response to progressive urbanisation. This is a critical knowledge gap, potentially leading to biases in the interpretation of previous results, especially if there is a time lag in the response of biodiversity to land-use change.

This project seeks to understand the relationship between biodiversity and urbanisation, using large-scale, long-term data from the UK on biodiversity, land-use and environmental conditions. We will investigate the response of different measures of biodiversity – at each site individually (alpha diversity), between sites (beta diversity), and regionally (gamma diversity) – as urbanisation has progressed. The integration of data collected over time at a broad geographical scale will help distinguish, for the first time, key factors that modulate the rate and directionality of biodiversity change with urbanisation.

Specifically, the project asks:

1) How do environmental conditions (climate, physical environment, land use, earlier species richness) affect the relationship between urbanisation and biodiversity and how it changes over time?

2) What is the effect of the progressive increase of urban land cover on alpha diversity (numbers of species and functional groups), beta diversity (differences in community composition) and gamma diversity (regional diversity)?

Answering these questions will fundamentally advance our understanding of how anthropogenic habitat change shapes biodiversity. Moreover, we will gain insights into how specific drivers of loss and gain can affect different aspects of biodiversity which will enable us to make specific recommendations for urban planning to encourage more sustainable and biodiverse cities.

We will address these questions using the Breeding Bird Survey (BBS), a dataset held by the British Trust for Ornithology (BTO), consisting of 25 years of species abundance data for avian communities. We will integrate, for the first time, this biodiversity dataset with data on land-use change from the NERC Centre of Ecology and Hydrology, as well as environmental data and climatic data collected during the same time period.

See http://www.iapetus.ac.uk/wp-content/uploads/2018/10/IAP2-18-03_Glasgow_Dominoni-1.pdf for more details.