A novel method for fine-scale biodiversity assessment and prediction across diverse urban landscapes reveals social deprivation-related inequalities in private, not public spaces

Abstract

The value of urban biodiversity is increasingly emphasised from both social and ecological perspectives, as biodiversity has been linked to providing multiple benefits ranging from supporting city sustainability to enhancing the health and well-being of individual residents. At present many urban studies lack integrated methods of assessing urban biodiversity that would allow the capture of both social and ecological values of green space and enable better management and planning for urban biodiversity. Here we introduce a method of scoring urban habitats at a fine scale, which measures habitat attributes that act as biodiversity indicators common to both social and ecological fields. This provides a single, comparable score that represents the capacity of habitats to support biodiversity and people’s connection to that biodiversity. Our results show a clear ranking of urban spaces from those characterised as being wilder and greener, to those dominated by paved surfaces that are more highly managed. We applied this scoring approach to predict and compare biodiversity across neighbourhoods in three New Zealand cities. We found biodiversity across neighbourhoods was significantly related to socioeconomic class, due mainly to the greater cover of mature gardens of high biodiversity value in regions of higher socio-economic status. As such, while all neighbourhoods provided opportunities for residents to connect to nature through public green space, those people living in more deprived neighbourhoods are less likely to be exposed to nearby biodiverse spaces, and therefore may encounter fewer opportunities to connect to nature and gain the benefits which urban biodiversity can afford.