Australian Urban Environments Research Articles

Sensor-based indoor air temperature prediction using deep ensemble machine learning: An Australian urban environment case study

Accurate prediction of indoor temperature is critical for climate change adaptation and occupant health. The aim of this study is to investigate an improved deep ensemble machine learning framework (DEML), by adjusting the model architecture with several machine learning (ML) and deep learning (DL) approaches to forecast the sensor-based indoor temperature in the Australian urban environment. We collected ambient station-based temperatures, satellite-based outdoor climate characteristics, and low-cost sensor-based indoor environmental metrics from 96 devices from August 2019 to November 2022, and established DEML with a rolling windows approach to assess the prediction stability over time. The DEML model was compared with several benchmark models, including Random Forest (RF), Support Vector Machine (SVM), eXtreme Gradient Boosting (XGboost), Long-short term memory (LSTM), and Super Learner model (SL). A total of 13,715 days [median: 341 days; IQR (the interquartile range): 221–977 days] of low-cost sensor-based indoor temperature were included in 25 commercial and residential buildings across eight cities. The prediction performance of DEML was superior to the other five benchmark models in most of the sensors [coefficients of determination (R2) of 0.861–0.990 and root mean square error (RMSE) of 0.125–0.886 °C], followed by RF and SL algorithms. DEML consistently achieved high accuracy across different climate zones, seasons, and building types, which could be used as a crucial tool for optimizing energy use, maintaining occupant comfort and health, and adapting to the impacts of climate change.

What is a parked bicycle? Vehicle fleet characteristics in Australia

Bicycle parking facilities are an important part of the transport system and their design can make bicycle transport more convenient. At a detailed level, the design of bicycle parking devices depends on how they relate to the bicycle's properties. This research seeks to provide a more detailed understanding of the characteristics and fleet of bicycles to inform better policy and practice. Set in Australia, an urbanised country aiming to increase a presently low bicycle mode share, the results are potentially useful to other low bicycle mode share cultures. Visual analysis reveals that although the relevant Australian standard describes a spatial envelope for bicycles, the envelope introduces a treatment of bicycle geometry at odds with vehicle characteristics; namely the contradiction that the spatial envelope in the standard significantly over states the volume of a bicycle, while at the same time the handlebars of the bicycle are inadequately accommodated. A random sample of 180 parked bicycles in Australian urban environments provides a detailed geometry database and shows that the Australian bicycle fleet is heterogeneous around clusters of geometry reflecting industry standards, but does not match with the spatial envelope provided in the standard. Photographic observations of these bicycles provide an insight into bicycle characteristics and parking behaviours, in particular revealing that 55% of the sample bicycles were not equipped with kick stands and thus depend on parking infrastructure for stability. Evidence from the field suggests that some bicycle users are willing to park bicycles more closely than suggested in the standard.

Metatranscriptomic Analysis of Virus Diversity in Urban Wild Birds with Paretic Disease.

Wild birds are major natural reservoirs and potential dispersers of a variety of infectious diseases. As such, it is important to determine the diversity of viruses they carry and use this information to help understand the potential risks of spillover to humans, domestic animals, and other wildlife. We investigated the potential viral causes of paresis in long-standing, but undiagnosed, disease syndromes in wild Australian birds. RNA from diseased birds was extracted and pooled based on tissue type, host species, and clinical manifestation for metagenomic sequencing. Using a bulk and unbiased metatranscriptomic approach, combined with clinical investigation and histopathology, we identified a number of novel viruses from the families Astroviridae, Adenoviridae, Picornaviridae, Polyomaviridae, Paramyxoviridae, Parvoviridae, and Circoviridae in common urban wild birds, including Australian magpies, magpie larks, pied currawongs, Australian ravens, and rainbow lorikeets. In each case, the presence of the virus was confirmed by reverse transcription (RT)-PCR. These data revealed a number of candidate viral pathogens that may contribute to coronary, skeletal muscle, vascular, and neuropathology in birds of the Corvidae and Artamidae families and neuropathology in members of the Psittaculidae The existence of such a diverse virome in urban avian species highlights the importance and challenges in elucidating the etiology and ecology of wildlife pathogens in urban environments. This information will be increasingly important for managing disease risks and conducting surveillance for potential viral threats to wildlife, livestock, and human health.IMPORTANCE Wildlife naturally harbor a diverse array of infectious microorganisms and can be a source of novel diseases in domestic animals and human populations. Using unbiased RNA sequencing, we identified highly diverse viruses in native birds from Australian urban environments presenting with paresis. This research included the clinical investigation and description of poorly understood recurring syndromes of unknown etiology: clenched claw syndrome and black and white bird disease. As well as identifying a range of potentially disease-causing viral pathogens, this study describes methods that can effectively and efficiently characterize emergent disease syndromes in free-ranging wildlife and promotes further surveillance for specific pathogens of potential conservation and zoonotic concern.

A Clean Air Plan for Sydney: An Overview of the Special Issue on Air Quality in New South Wales

This paper presents a summary of the key findings of the special issue of Atmosphere on Air Quality in New South Wales and discusses the implications of the work for policy makers and individuals. This special edition presents new air quality research in Australia undertaken by (or in association with) the Clean Air and Urban Landscapes hub, which is funded by the National Environmental Science Program on behalf of the Australian Government’s Department of the Environment and Energy. Air pollution in Australian cities is generally low, with typical concentrations of key pollutants at much lower levels than experienced in comparable cities in many other parts of the world. Australian cities do experience occasional exceedances in ozone and PM2.5 (above air pollution guidelines), as well as extreme pollution events, often as a result of bushfires, dust storms, or heatwaves. Even in the absence of extreme events, natural emissions play a significant role in influencing the Australian urban environment, due to the remoteness from large regional anthropogenic emission sources. By studying air quality in Australia, we can gain a greater understanding of the underlying atmospheric chemistry and health risks in less polluted atmospheric environments, and the health benefits of continued reduction in air pollution. These conditions may be representative of future air quality scenarios for parts of the Northern Hemisphere, as legislation and cleaner technologies reduce anthropogenic air pollution in European, American, and Asian cities. However, in many instances, current legislation regarding emissions in Australia is significantly more lax than in other developed countries, making Australia vulnerable to worsening air pollution in association with future population growth. The need to avoid complacency is highlighted by recent epidemiological research, reporting associations between air pollution and adverse health outcomes even at air pollutant concentrations that are lower than Australia’s national air quality standards. Improving air quality is expected to improve health outcomes at any pollution level, with specific benefits projected for reductions in long-term exposure to average PM2.5 concentrations.

Flying-foxes in the Australian urban environment—community attitudes and opinions

The urban presence of flying-foxes (pteropid bats) in eastern Australia has increased in the last 20years, putatively reflecting broader landscape change. The influx of large numbers often precipitates community angst, typically stemming from concerns about loss of social amenity, economic loss or negative health impacts from recently emerged bat-mediated zoonotic diseases such as Hendra virus and Australian bat lyssavirus. Local authorities and state wildlife authorities are increasingly asked to approve the dispersal or modification of flying-fox roosts to address expressed concerns, yet the scale of this concern within the community, and the veracity of the basis for concern are often unclear. We conducted an on-line survey to capture community attitudes and opinions on flying-foxes in the urban environment to inform management policy and decision-making. Analysis focused on awareness, concerns, and management options, and primarily compared responses from communities where flying-fox management was and was not topical at the time of the survey. While a majority of respondents indicated a moderate to high level of knowledge of both flying-foxes and Hendra virus, a substantial minority mistakenly believed that flying-foxes pose a direct infection risk to humans, suggesting miscommunication or misinformation, and the need for additional risk communication strategies. Secondly, a minority of community members indicated they were directly impacted by urban roosts, most plausibly those living in close proximity to the roost, suggesting that targeted management options are warranted. Thirdly, neither dispersal nor culling was seen as an appropriate management strategy by the majority of respondents, including those from postcodes where flying-fox management was topical. These findings usefully inform community debate and policy development and demonstrate the value of social analysis in defining the issues and options in this complex human–wildlife interaction. The mobile nature of flying-foxes underlines the need for a management strategy at a regional or larger scale, and independent of state borders.

Impact of green roofs on stormwater quality in a South Australian urban environment

Green roofs are an increasingly important component of water sensitive urban design systems and can potentially improve the quality of urban runoff. However, there is evidence that they can occasionally act as a source rather than a sink for pollutants. In this study, the water quality of the outflow from both intensive and extensive green roof systems were studied in the city of Adelaide, South Australia over a period of nine months. The aim was to examine the effects of different green roof configurations on stormwater quality and to compare this with runoff from aluminium and asphalt roofs as control surfaces. The contaminant concentrations in runoff from both intensive and extensive green roofs generally decreased during the study period. A comparison between the two types of green roof showed that except for some events for EC, TDS and chloride, the values of the parameters such as pH, turbidity, nitrate, phosphate and potassium in intensive green roof outflows were higher than in the outflows from the extensive green roofs. These concentrations were compared to local, state, national and international water quality guidelines in order to investigate the potential for outflow runoff from green roofs to be reused for potable and non-potable purposes. The study found that green roof outflow can provide an alternative water source for non-potable purposes such as urban landscape irrigation and toilet flushing.

School Choice: What Parents Choose

The educational system in Australia allows parents to have a choice when it comes to selecting a school for their children. Parents have become consumers in an educational market, and schools, including Christian schools, now find themselves operating in a competitive space. The research reported in this two-part article sought to explore the factors that influence parents’ choice of school for their children using a mixed methods approach. Parents with students attending Christian schools in an Australian urban environment completed a total of 102 School Choice questionnaires, and 17 families with children in schools were interviewed.

Watering our cities

Urban drainage infrastructure is generally designed to rapidly export stormwater away from the urban environment to minimize flood risk created by extensive impervious surface cover. This deficit is resolved by importing high-quality potable water for irrigation. However, cities and towns at times face water restrictions in response to drought and water scarcity. This can exacerbate heating and drying, and promote the development of unfavourable urban climates. The combination of excessive heating driven by urban development, low water availability and future climate change impacts could compromise human health and amenity for urban dwellers. This paper draws on existing literature to demonstrate the potential of Water Sensitive Urban Design (WSUD) to help improve outdoor human thermal comfort in urban areas and support Climate Sensitive Urban Design (CSUD) objectives within the Australian context. WSUD provides a mechanism for retaining water in the urban landscape through stormwater harvesting and reuse while also reducing urban temperatures through enhanced evapotranspiration and surface cooling. Research suggests that WSUD features are broadly capable of lowering temperatures and improving human thermal comfort, and when integrated with vegetation (especially trees) have potential to meet CSUD objectives. However, the degree of benefit (the intensity of cooling and improvements to human thermal comfort) depends on a multitude of factors including local environmental conditions, the design and placement of the systems, and the nature of the surrounding urban landscape. We suggest that WSUD can provide a source of water across Australian urban environments for landscape irrigation and soil moisture replenishment to maximize the urban climatic benefits of existing vegetation and green spaces. WSUD should be implemented strategically into the urban landscape, targeting areas of high heat exposure, with many distributed WSUD features at regular intervals to promote infiltration and evapotranspiration, and maintain tree health.

Streetscape biodiversity and the role of bioretention swales in an Australian urban environment

For the successful development of Water Sensitive Urban Design (WSUD) or Low Impact Development (LID) as a relatively new concept for stormwater management, it is necessary to understand the effect of these systems on urban ecology. This study determined the effect of bioretention swales as a type of vegetated WSUD system on urban biodiversity. The biodiversity potential of nine bioretention swales and nine corresponding green spaces in the Melbourne area were compared. Invertebrates captured by sweep netting were used as biodiversity indicators. The number of species, species richness and diversity were higher in bioretention swales than in gardenbed and lawn-type green spaces, respectively. The invertebrate communities in these landscapes were affected by mid-stratum vegetation coverage, the number of flowering plants, pH and the slope characteristics of the bioretention swales. These effects might be a response of the invertebrate species to increased refuge and food resources available in these landscapes. Changing conventional planting strips in streets to bioretention swales has promising potential for enhancing urban biodiversity. In particular, reducing the area of lawn-type green spaces to promote sustainable development is recommended. The outcomes of this research have practical implications for landscape designers and managers whose aim is to conserve invertebrate diversity in urban settings.

Foraging height and landscape context predict the relative abundance of bird species in urban vegetation patches

In Australian urban environments, revegetation and vegetation restoration are increasingly utilized conservation actions. Simple methods that help assess the utility of urban vegetation for bird species will help direct this effort for bird conservation purposes. We therefore examine whether ecological principles can be used to predict, a priori, the relative abundance of different bird species in urban vegetation. Our model proposes that a bird species will be in greater abundance where vegetation structure better reflects its foraging height requirements, and this relationship will be moderated by the landscape context of the patch. To quantify and test this model, we created an index to rank existing and revegetated urban vegetation sites in order of greatest expected abundance for each of 30 bird species. We tested this model, alongside two simpler models which consider landscape context and foraging height preferences alone, using bird abundance data from 20 woodland remnants and 20 revegetated sites in Brisbane, Australia. From these bird abundance data, we calculated the relative abundance of each species between the top-ranking sites and lowest-ranking sites. The model which incorporated both foraging height requirements and landscape context made predictions that were positively correlated with the data for 77% of species in remnant vegetation and 67% in revegetation. The results varied across species groups; for example, we achieved lower predictive success for canopy foraging species in the less mature revegetation sites. Overall, this model provided a reasonable level of predictive accuracy despite the diversity of factors which can influence species occurrence in urban landscapes. The model is generic and, subject to further testing, can be used to examine the effect of manipulating vegetation structure and landscape context on the abundance of different bird species in urban vegetation. This could provide a cost-effective tool for directing urban restoration and revegetation efforts.

In Vitro Model of Vitamin D Synthesis by UV Radiation in an Australian Urban Environment

Vitamin D, an important constituent of human health, is produced through the exposure of human skin to short wave (280-315 nm) ultraviolet radiation (UV). We aimed to establish whether an urbanized environment with tall buildings in close proximity (an "urban canyon") significantly reduced the capacity of sunlight to synthesize vitamin D, when compared with a typical suburban area (∼2.5 km away); and to investigate the association of UV and vitamin D production with pollution, temperature, and humidity. Measurements of ambient UV (295-400 nm) (using a portable photometer/radiometer and detector) and synthesized vitamin D (from an in vitro model) were taken regularly at urban and control sites over 3 months in Brisbane, Australia. During a typical 20 min measurement, urban and control sites received 0.26 and 1.03 W m(-2) mean total UV respectively (P < 0.001), and produced 0.12 and 0.53 μg mL(-1) mean vitamin D (P < 0.001). Pollution, temperature and humidity were not associated with UV or vitamin D production. This demonstrates a large difference in vitamin D synthesis between an urban canyon and a nearby control site. Although the results cannot be directly applied to humans, they emphasize the need for further study of human vitamin D production in urban environments.

Abundance of Pseudallescheria/Scedosporium species in the Australian urban environment suggests a possible source for scedosporiosis including the colonization of airways in cystic fibrosis

Members of the Pseudallescheria/Scedosporium species complex are emerging opportunistic fungal pathogens which have the capacity to colonize patients with damaged airways, including those with cystic fibrosis (CF). Assuming human infection is acquired via inhalation of fungal spores from the environment, we performed a qualitative environmental survey encompassing 25 urban, semirural and rural sites in the greater Sydney region to determine the prevalence of Pseudallescheria/Scedosporium species. Soil sampling revealed an abundance of Pseudallescheria/Scedosporium, particularly in locations associated with high human activity. No variation was noted during repeated sampling at different times of the year. Strains of Scedosporium aurantiacum were most frequently isolated (54.6%), followed by Scedosporium prolificans (43%), P. boydii (2.1%) and S. dehoogii (0.3%). The findings coincide with the relatively high prevalence of Scedosporium infections in Australia and their presence as colonizers in CF patients. They emphasize the importance of environmental studies to assess the clinical risk of infection.

Factors affecting terrestrial invertebrate diversity in bioretention basins in an Australian urban environment

Biodiversity conservation is a significant challenge for urban planning and management. When new urban development strategies are introduced, their effects on urban biodiversity are often unknown and may have serious consequences for conservation. A relatively new urban development strategy for sustainable urban water cycle management is Water Sensitive Urban Design (WSUD). While this strategy has been implemented in Australia over the past decade, little is known about the impacts on biodiversity from its application. A field investigation was conducted on 12 bioretention basins, which are a type of vegetated WSUD system. The study used invertebrates captured through pitfall trapping as biodiversity indicators and was conducted in the Melbourne area during the summer of 2006–2007. It investigated the effect of ten habitat factors separately and as group factors on biodiversity of the systems. It also examined how invertebrates were distributed within these WSUD systems. The results suggested that greater leaf/plant litter depth or a combination of greater leaf/plant litter depth and larger number of plant taxa is a significant contributor to biodiversity in bioretention basins. Therefore, the design and management of bioretention basins should consider increasing these habitat factors as key elements to promote biodiversity. The distribution pattern of invertebrates within the systems increased from the edges towards the centre suggesting that designing the sites should consider shape and size to create larger interior habitats for enhancing biodiversity. The results of this study are important for the design and management of bioretention basins to improve biodiversity conservation in urban environments.

Assessment of the UVR Protection Provided by Different Tree Species

In recent years, SunSmart campaigns have emphasized the importance of the use of shade as a strategy in the reduction of human exposure to solar UV radiation (UVR), particularly in early life with the provision of shade in schools. Trees can play an important role in shade provision, either as the main shade provider or to augment shade structures and increase UVR protection provided to the general population. A study to measure the protection provided by a range of trees common in Australian urban environments was undertaken during the summers of 2004/2005 and 2005/2006. Solar UVR beneath the trees was measured using UVR sensitive polysulphone badges positioned horizontally within the shaded area and were compared with those in full sunshine to give an indication of the protection provided. Measurements made on sunny days during the months of October to April indicated that the shade cover provided by the trees depended upon the tree species and changed with season as a result of changing foliage and sun angles. Measured protection factors ranged from 5 to 10 and were generally a maximum in the height of summer when the sun was highest in the sky and the foliage was densest.

Some examples of water recycling in Australian urban environments: a step towards environmental sustainability

This paper discusses the concepts and results from two contrasting types of water recycling initiatives in Australia. The first type of initiative is a centralised scheme based on local authorities recycling sewage effluent and/or stormwater in urban areas. A new urban subdivision in Queensland (Springfield) is provided as an example of such a centralised scheme, with uses ranging from dual reticulation, to public space irrigation, to urban lakes. The importance of strong public consultation and partnership is stressed for scheme success. A second example of a centralised scheme is an upmarket subdivision in Adelaide, South Australia (Mawson Lakes), where stormwater and recycled effluent are designed to supply in excess of 70% of the community's total water requirement. Scheme success is highly probable because of the ready adoption of innovative water supply alternatives by South Australians. The other type of initiative operates at a household scale (Healthy Home) and demonstrates that reinventing old ideas using new technologies can allow urban households to become largely self reliant for their potable and non-potable water needs, at least in high rainfall coastal areas. However, the cost effectiveness of this self reliance will require a substantial change in the sharing of savings from deferred public infrastructure costs. We include for comparison an analysis by Coombes et al. for the Lower Hunter region which clearly demonstrates that adoption of water sensitive urban design features, such as rainwater tanks in new developments, is not only more cost effective than traditional infrastructure solutions, but also allows the deferral of new urban water supply dams by the order of decades. We conclude the paper with the observation that advances in incorporating externalities into water development economics, the "trickle down" effect of new distributed technologies, and the growing desire by urban communities to live within the capacity of their regional ecosystems will probably ensure that reforms in the urban water and wastewater cycles will pioneer the way to genuinely sustainable and liveable urban communities in the near future. In short, the Ecological Footprint of urban development will be substantially reduced.

Nest predation in Australian urban environments and the role of the pied currawong, Strepera graculina

Abstract An experiment, involving 2000 members of the public, determined the identity of nest predators in urban environments. Experimental nests of halved tennis balls covered with coconut fibre and wool were manufactured to resemble the nests of willie wagtails, Rhipidura leucophrys. The identity of predators was determined by analysis of imprints left in artificial eggs made of coloured modelling clay. Sixty‐four per cent of nests were preyed upon, with most predation being the result of large birds. Direct observations of predation (n = 134) indicated that pied currawongs were the most common large bird, accounting for 52% of all predation. Predation incidence was higher in gardens with more trees and in which kookaburras, Dacelo novaeguineae, were fed frequently. Among nests placed in trees, nest predation was correlated with nest height. Eggs camouflaged by speckling experienced a similar incidence of predation to plain eggs. This study provides evidence to support the contention that pied currawongs are a major threat to the persistence of small birds in Australian urban environments.

Age differences in adolescent identity exploration and commitment in urban and rural environments

Sociocultural context may play an important role in identity development by shaping the opportunities adolescents are facing. To examine this, adolescents living in urban and rural environments were compared in terms of age differences in identity exploration and commitment. Younger (13–14-year-olds) and older (16–17-year-olds) males and females from urban and rural areas in both Australia ( n=367) and Finland ( n=316) were investigated. The participants completed the Exploration and Commitment Questionnaire which includes items concerning future education, occupation and family. The results showed that the older youths living in Australian urban environments showed higher levels of exploration and commitment concerning both their future education and occupation than the younger ones, whereas there was an age-related decrease in these variables among adolescents living in Australian rural areas. No urban vs. rural differences were found for Finnish adolescents.

Breeding Biology of Brushtail Possums Trichosurus vulpecula (Marsupialia, Phalangeridae) in Captivity.

The brushtail possum is a common arboreal marsupial that is well adapted to the Australian urban environment and to rearing in captivity. Data obtained from 100 female possums housed in a semi-captive colony over a 7 year period demonstrate the reproductive capability of this marsupial. The main breeding season is from March to June with a declining number of births occurring from July to October. The possums gave birth to 259 single young and one set of twins. The range of the lactation period was from 177 to 200 days with the birth of the subsequent young occurring at 188.4 ± 4.1 days post partum (SD, n = 5). The growth rate of the young female possum varied greatly after day 100 post partum, the mean body weight of possums at day 172, being 753.0 ± 76.2g (SD, n = 5) with a range of 685 to 851 g. Female possums, with a mean body weight of 2171 ± 388g, gave birth to their first litter on day 345.9 ± 69.3 days postpartum (mean, SD, n = 7). Although two female possums trapped in the wild were held in captivity for 64 and 63.4 months and one possum bred in captivity had a life span of 51.5 months, the mean life span was 21.0 ± 12.5 months (SD, n =3D 8), with a range of 14.3 to 51.5 months. This life span is very variable and it is of interest to determine if this is an artefact of captivity or is also observed in the wild.