R. Matthew Beaty

Climate Change and Health in the Urban Environment: Adaptation Opportunities in Australian Cities

Urban populations are growing rapidly throughout the Asia-Pacific region. Cities are vulnerable to the health impacts of climate change because of their concentration of people and infrastructure, the physical (geographical, material, and structural) attributes of the built environment, and the ecological interdependence with the urban ecosystem. Australia is one of the most highly urbanized countries in the region and its already variable climate is set to become hotter and drier with climate change. Climate change in Australia is expected to increase morbidity and mortality from thermal stress, bacterial gastroenteritis, vector-borne disease, air pollution, flooding, and bushfires. The cost and availability of fresh water, food, and energy will also likely be affected. The more vulnerable urban populations, including the elderly, socioeconomically disadvantaged groups, and those with underlying chronic disease, will be most affected. Adaptation strategies need to address this underlying burden of disease and inequity as well as implement broad structural changes to building codes and urban design, and infrastructure capacity. In doing so, cities provide opportunities to realize “co-benefits” for health (eg, from increased levels of physical activity and improved air quality). With evidence that climate change is underway, the need for cities to be a focus in the development of climate adaptation strategies is becoming more urgent.

Pocket parks in a compact city: how do birds respond to increasing residential density?

Abstract The desire to improve urban sustainability is motivating many city planners to adopt growth strategies that increase residential density, leading to substantial changes to urban landscapes. What effect this change will have on biodiversity remains unclear, but it is expected that the role of public greenspace in providing wildlife habitat will become critical. We explored the role of urban “pocket parks” as habitat for birds, and how this role changed with increasing residential density in the surrounding neighbourhood. We found that parks in neighbourhoods with high levels of public greenspace (corresponding to less residential land) supported more bird species and individuals overall, and more woodland-dependent species, insectivores and hollow-nesters. Total greenspace area was more important (included in the best ranked models for all bird responses) than the configuration (number, average size and connectivity) of greenspace patches. The majority of species were common suburban birds, indicating that species we assume are tolerant to urban areas will be negatively affected by increasing residential density. Parks form part of an interconnected network of urban open space. For parks to continue to support a diverse native bird community, the network must be viewed, managed, and maintained in its entirety. We suggest three key management actions to improve the bird diversity values of urban greenspaces in compact cities: (1) Increase urban greenspace cover in residential neighbourhoods. (2) Increase vegetation structure in greenspace. (3) Encourage homeowners to plant trees and shrubs.

Rising tides: adaptation policy alternatives for coastal residential buildings in Australia

In this work, a risk-based assessment method and benefit-cost analysis to support policy decisions for adapting Australian coastal residential buildings to future coastal inundation hazard is presented. Future coastal inundation is mainly influenced by storm surge and rising sea level. The sea level rises projected by the A1FI, A1B and B1 emissions scenarios developed by the Intergovernmental Panel on Climate Change are considered. The effects of economic and population growth are accounted for by three urban development scenarios: (a) business as usual, (b) urban consolidation and (c) regional development. The adaptation policy actions investigated include a ‘protect’ stance (involving the construction of seawalls), an ‘accommodate’ stance that mandates raising house floors to a certain height (e.g. at heights of 100-year events) and an ‘avoid’ stance that limits new developments in hazardous areas. Policy stances classified as reactive (i.e. action taken after damage being incurred) and anticipatory (i.e. action taken anticipating what will happen) are developed for asset investment choices. In general, adaptation costs are an order of magnitude lower than benefits gained from avoided damages. The results highlight that adaptation action for coastal inundation has a no-regrets character and provides a strong case for reform to ensure that Australia-wide adaptation opportunities are realised.

Citizen science program shows urban areas have lower occurrence of frog species, but not accelerated declines

Understanding the influence of landscape change on animal populations is critical to inform biodiversity conservation efforts. A particularly important goal is to understand how urban density affects the persistence of animal populations through time, and how these impacts can be mediated by habitat provision; but data on this question are limited for some taxa. Here, we use data from a citizen science monitoring program to investigate the effect of urbanization on patterns of frog species richness and occurrence over 13 years. Sites surrounded by a high proportion of bare ground (a proxy for urbanization) had consistently lower frog occurrence, but we found no evidence that declines were restricted to urban areas. Instead, several frog species showed declines in rural wetlands with low-quality habitat. Our analysis shows that urban wetlands had low but stable species richness; but also that population trajectories are strongly influenced by vegetation provision in both the riparian zone and the wider landscape. Future increases in the extent of urban environments in our study area are likely to negatively impact populations of several frog species. However, existing urban areas are unlikely to lose further frog species in the medium term. We recommend that landscape planning and management focus on the conservation and restoration of rural wetlands to arrest current declines, and the revegetation of urban wetlands to facilitate the re-expansion of urban-sensitive species.