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Zoonotic disease vectors, their wildlife hosts, and the surrounding landscape interact in complex ways that vary spatially, temporally and with anthropogenic change. Ticks (Acari: Ixodidae) are one of the most important vectors of human disease globally but managing the risk of tick bites in urban areas requires a detailed understanding of these complex vector-host-environment relationships at multiple spatial scales. Extensive knowledge gaps of these interactions in Australia limits options for managing ticks and exacerbates human-wildlife conflict. To address this, we used an online survey to determine the potential drivers of human-tick encounters operating at the local, yard scale and at the broader, landscape scale in a peri-urban area of Australia. We explored the relationships between reported tick encounters in yards and yard traits, host sightings (yard-scale) and broader landscape traits (landscape-scale). We found that sightings of potential hosts such as long-nosed bandicoots (Perameles nasuta) and brush-turkeys (Alectura lathami), and broader landscape traits such as distance to wet sclerophyll forest, were important predictors of reported tick encounters. Yard traits such as garden mulching and leaf litter cover showed no relationships with tick encounters. However, garden mulching and the absence of pets were predictors of frequent bandicoot sightings in yards. Mulching over 20m2, moderate to dense leaf litter cover on lawns, and living adjacent to bush were predictors of frequent brush-turkey sightings in yards. Our results suggest that residents may be able to reduce tick encounter risk by making yards less attractive to potential hosts. The observed relationships provide a critical foundation for field studies that can determine underlying mechanisms and inform appropriate tick management in urban environments. [ABSTRACT FROM AUTHOR]

Invertebrates comprise the most diversified animal group on Earth. Due to their long evolutionary history and small size, invertebrates occupy a remarkable range of ecological niches, and play an important role as "ecosystem engineers" by structuring networks of mutualistic and antagonistic ecological interactions in almost all terrestrial ecosystems. Urban forests provide critical ecosystem services to humans, and, as in other systems, invertebrates are central to structuring and maintaining the functioning of urban forests. Identifying the role of invertebrates in urban forests can help elucidate their importance to practitioners and the public, not only to preserve biodiversity in urban environments, but also to make the public aware of their functional importance in maintaining healthy greenspaces. In this review, we examine the multiple functional roles that invertebrates play in urban forests that contribute to ecosystem service provisioning, including pollination, predation, herbivory, seed and microorganism dispersal and organic matter decomposition, but also those that lead to disservices, primarily from a public health perspective, e.g., transmission of invertebrate-borne diseases. We then identify a number of ecological filters that structure urban forest invertebrate communities, such as changes in habitat structure, increased landscape imperviousness, microclimatic changes and pollution. We also discuss the complexity of ways that forest invertebrates respond to urbanisation, including acclimation, local extinction and evolution. Finally, we present management recommendations to support and conserve viable and diverse urban forest invertebrate populations into the future. [ABSTRACT FROM AUTHOR]

Street tree assemblages are a widespread natural component in cities and provide a range of ecosystem services. The spatial distribution of street tree assemblages within cities, however, is not uniform. We assessed the air purification benefits provided by street trees in Shenyang, China, to examine how urban form, urban geography and drivers of vegetation management affect this ecosystem service. The i-Tree Street Model was utilized to evaluate air purification benefits provided by street trees. We analyzed the results using two indices, with values expressed in US dollars (USD, $): the per kilometer benefit (PKB) and average tree benefit (ATB). Neither index displayed a consistent trend across the human population density gradient or along the urban-suburban continuum. The district with the highest PKB and ATB is neither the oldest nor the newest one to develop, but rather the one that began to develop around 2002. We conclude that public policy is a main driver of vegetation management, especially for street trees, because street tree abundance is closely related to road construction, which, in turn, is closely tied to economic development in a region. We also discovered no significant difference in the benefit of street tree assemblages along the urban-suburban continuum. That's probably because all areas within the different beltways contain mature street trees, the time-lag effect for growth is inconsequential. We recommend that the dynamic variations of street tree assemblages over a certain time span be taken into consideration when examining the effects of urban sprawl on ecosystem services provided by street tree assemblages. [ABSTRACT FROM AUTHOR]

It is important to understand how animals respond to changes in landscape structure, especially when considering habitat alteration and urbanization. Using the burrowing owl (Athene cunicularia) as an ecological model we tested two hypotheses: (1) the landscape of urban areas influences trajectories of the burrowing owl, which responds changing its displacement patterns, and (2) models incorporating species-specific traits, such as stochasticity and landscape perception, better predict flight trajectories than least-cost path models. Thirty owls were captured at the Brasília International Airport, fitted with VHF transmitters, and released in random locations within 30 km of the airport. We generated a habitat suitability map for use as a resistance raster to model flight trajectories: one model was based on the least-cost path, and four models included stochasticity and variations of the owls' landscape perception and dependency on natural ecosystems. Observed trajectories were compared with those predicted by models using the following metrics extracted from the trajectories: mean habitat suitability values, sinuosity, and length. The best generalized linear models were selected using the Akaike information criterion. The owls dispersed through areas with a lower cost than expected by chance (z = 104.65, p < 0.05). More complex models performed better than the least-cost path model for suitability (r2 = 0.18, p > 0.05), sinuosity (r2 = 0.03, p > 0.05), and length (r2 = 0.37, p > 0.05). Our results demonstrate that landscape information influences flight trajectories, and models incorporating landscape perception and stochasticity better predict burrowing owl flight trajectories. [ABSTRACT FROM AUTHOR]

Migratory birds play an important role in large-scale movements of ticks and tick-borne pathogens, yet little is known about tick infestation of resident birds (e.g., non-migratory species and migratory species during the breeding season), especially in urban ecosystems. We captured birds during the breeding season in parks and greenspaces in Oklahoma City, Oklahoma, USA, to evaluate overall tick infestation patterns and to determine if urbanization influences infestation prevalence (the proportion of birds parasitized) and intensity (the number of ticks on infested birds). Of 459 birds, 111 (24.2%) had ≥ 1 tick, a high proportion of infestation compared with past North American studies. The most frequently infested species were Carolina Wren (Thryothorus ludovicianus; 56%), Brown Thrasher (Toxostoma rufum; 37%), and Northern Cardinal (Cardinalis cardinalis; 27%). The Lone Star Tick (Amblyomma americanum) comprised half (51%; n = 322) of all ticks on birds; other species sampled included Gulf Coast Tick (A. maculatum) (36%) and Rabbit Tick (Haemaphysalis leporispalustris) (13%). Urbanization intensity (i.e., the percentage of developed land around sites) was inversely related to infestation prevalence for all birds combined and for Carolina Wren, but intensity of infestation was unrelated to urbanization. Our results suggest that non-migratory and migratory birds during sedentary periods are important carriers of ticks in urban areas, and that tick infestation patterns can be influenced by the level of urbanization in the surrounding landscape. Clarifying how urban birds influence tick populations, and how urbanization shapes bird-tick interactions, will increase understanding of tick-borne disease ecology in urban ecosystems. [ABSTRACT FROM AUTHOR]

We introduce a conceptual model of the urban forest patch as a complex social-ecological system, incorporating cross-scale interactions. We developed this model through an interdisciplinary process engaging social and ecological scientists and urban land management decision makers, with a focus on temperate forest social-ecological systems. In this paper, we place the production and management of urban forest patches in historical perspective, present a conceptual model of urban forest patches within a broader regional context, and identify a series of research questions to highlight future directions for research on urban forest patches. This conceptual model identifies how spatial and temporal social-ecological drivers interact with patch-level conditions at multiple scales. Our integrative approach can provide insights into the role of social-ecological drivers in shaping forest health, biodiversity, and benefits forest patches provide to people in urban and urbanizing regions, with direct implications for decision-making to improve management outcomes. [ABSTRACT FROM AUTHOR]

Freshwater ecosystems are under threat from habitat loss, partly due to urban expansion. However, some elements of urban freshwaters are already integral parts of the urban landscape and so are more resilient to loss, representing opportunities for the enhancement of freshwater resources within cities. This study investigated the biodiversity value of the Leeds-Liverpool Canal in Leeds, UK, in relation to its landscape context. Specifically, we tested the hypotheses that (i) biodiversity value is lowest nearest to the urban core, and (ii) the pattern of canal locks structured ecological communities. Nutrients, metals and dissolved carbon all existed at relatively low concentrations, contrary to what is often seen in urban water bodies, although concentrations were higher in the urban core. This gradient of chemical stress was associated with a decline in macroinvertebrate diversity towards the city centre, which manifested as pollution-sensitive taxa being excluded from this area. Community structures were found to vary between groups of sampling sites separated by locks, suggesting that locks may act as barriers for aquatic invertebrates by restricting dispersal. The results in this study indicate that canals in urban areas can be high-quality habitats, despite the associated anthropogenic stressors, and locks may represent a unique model for researching relationships between connectivity and community structure. [ABSTRACT FROM AUTHOR]

Domestic gardens are the major contributor to greening the spatial plan in some compact cities. Irbid, Jordan is a densely populated city that has limited and deteriorating natural vegetation and is located in an arid to semi-arid climate. We investigated the density of domestic gardens (proportion of gardened residential units) in Irbid city and explored some properties of domestic gardens. The research focused on the city domestic garden types, their distribution, gardens proportions and association to household economic status and parcel area. Four hundred and thirty residential units were selected randomly using Geographical Information Systems (GIS). The sample size for each district was identified proportionally relative to the district's total residential units. Parcel area, district population, household income and landscape properties information were obtained from GIS maps, homeowners' interviews or on site observations. Sixty-two percent of the city residential units had gardens and those gardens were distributed unequally (21–100%) among city districts. Rural areas had higher garden densities (proportions) compared to that at the city center. Around 50% of the city gardens were utilitarian and were concentrated in the rural areas, while the aesthetically designed gardens represented 21% of the total gardens and were significantly concentrated near the core urban area of the city. Around 53% of the city domestic gardens were categorized as side yards. The districts' domestic garden proportions and parcel sizes were positively correlated. The proportions of aesthetic gardens were positively correlated with districts' median income while utilitarian garden proportions strongly and inversely correlated with districts income. This knowledge about the proportions of domestic gardens distribution, trends, garden attributes and other factors that interfere with the existence and shape of domestic gardens has implications for species composition and can serve as a basis for green infrastructure planning, sustainable environmental planning strategies, and land use policies. [ABSTRACT FROM AUTHOR]

Urbanization has a massive impact on ecological function and impedes the provisioning of environmental services. The interaction between urbanization and the environment has been researched extensively. However, the existing research focused on the urbanization characteristics of large metropolitan areas. In this paper, we investigate the urban fragmentation patterns of small and mid-sized cities in Idaho, USA. To capture the urban morphology for each site within the study we use both concentric ring and transect analysis as well as several spatial/landscape metrics. Our results show that the characteristics of urbanization in small and mid-sized cities (and those in second-tier regions that attract relatively little scholarly attention) are consistent with growth phase theory of urbanization, urbanization along a gradient, and urbanization patterns of metropolises. [ABSTRACT FROM AUTHOR]

New residential developments in the Southeastern United States peaked in early 2006, but since then declined leaving numerous residential developments stalled in various stages of construction. The status of 119 previously identified (2009) abandoned residential housing developments was reinvestigated in 2013 using the most current available high-resolution aerial photography with a randomly selected number of sites (40) in Greenville, Pickens and Spartanburg Counties in South Carolina. The original land cover before any housing developments was determined based on historical infrared aerial imagery (1999). Development sites were categorized based on the development status: no change, active development or completed development. Site locations were used to determine network distance to major cities and schools to determine if location is related to current development status. Historical aerial photos showed that the majority of land originally developed was forest land. Site visits indicated that 24 out of 40 sites previously identified as abandoned are in various stages of recent construction (three out of five in Pickens County, three out of 15 in Spartanburg County and 18 out of 20 in Greenville County). Of the 19 sites that were labeled as active through a field visit 15 were positively identified as active by using the aerial imagery. Sites with recent construction were closest to schools, but distance to urban centers was not a factor. This study suggests that proximity to schools may be a driving factor in restarting previously abandoned developments. [ABSTRACT FROM AUTHOR]

Home gardens have been recognized as repositories of agricultural biodiversity across the world. The influence of socioeconomics and location-specific factors on urban gardening patterns merits continued study. Using Beijing Municipal Province in China, a rapidly urbanizing region, as a case study, we address two questions: 1) How do biodiversity patterns change between different urbanized regions in Beijing? 2) How do ecosystem services provided by Beijing home gardens change with socioeconomic status and location-based preferences of gardeners? We surveyed 104 home gardens in Beijing Municipal Province for plant biodiversity, abundance, and species ecosystem services (ES) (provisioning or cultural uses). The gardens were distributed across three urbanized regions (suburban, peri-urban, and exurban). We found that species biodiversity and abundance shift according to a hierarchy of need from ornamentals (cultural ES) to edibles (provisioning ES) with increasing distance from Beijing. These trends are related to reduced income, lowered food security, and lack of urban markets in exurban regions. Rarefaction curves indicate ornamental species drive β diversity. Ordination also showed a shift in species composition with increasing isolation from the city; Suburban and exurban gardens were the most different, while peri-urban gardens were similar to both others. Only exurban gardens had a positive relationship between species and area. High edible cover and high species density indicates that demand for edibles in exurban regions may be higher than space constraints allows. Our study better quantifies species biodiversity patterns in Beijing, and can inform urban planners about the value and usefulness of home garden space. [ABSTRACT FROM AUTHOR]

The urban heat island (UHI) effect is one of the important ecological effects of urbanization. This study focuses on the different effects of landscape patterns on LST within different land covers. The land cover was measured by surface biophysical components, including vegetation fraction (VF) and impervious surface area (ISA), acquired by a linear spectral mixture model (LSMM). LST was derived from Landsat-5 TM thermal infrared (TIR) data using the generalized single-channel method. Landscape patterns were measured by landscape metrics, including the Shannon diversity index (SHDI), the aggregation index (AI), patch density (PD), and fractal dimension area-weighted mean index (FRAC_AM). Shenzhen, a rapidly urbanizing city in China, was taken as the case study area. Results showed that VF and ISA are more important than spatial patterns in determining LST. However, these effects change in densely covered areas. VF and LST are negatively correlated, with the inflection of the regression curves being 45 %. In areas with VF lower than 45 %, the correlation between LST and VF is monotonically linear. In areas with VF higher than 45 %, landscape patterns can act to decrease LST. The aggregation index (AI) and the largest patch index (LPI) can contribute to decreasing LST significantly. Impervious surfaces contribute to high temperature, and the inflection point of the regression curves is 70 %. In areas with ISA higher than 70 %, a fragmented pattern of impervious surfaces can lower LST. These findings provide insights for planners into how the strategic use of landscape to mitigate UHI effects may vary for different land covers. [ABSTRACT FROM AUTHOR]

In this era of rapidly urbanising human populations, urban practitioners are under increasing pressure to create resilient and sustainable cities and towns. Urban ecologists currently have a unique opportunity to apply solid, evidence-based research to help create biodiversity-rich and sustainable cities and towns for the future. Unfortunately, there is currently a mismatch between the questions planners, designers and decision-makers are asking urban ecologists that would allow them to improve the biodiversity outcomes in urban areas, and the questions urban ecologists must ask to contribute to the development and application of the science of urban ecology. For a number of reasons, urban ecologists over the past 25 years have primarily focused on describing the patterns of biodiversity in cities and towns using broad, aggregate predictor variables (e.g., distance to city center, land-use, percent cover of impermeable surfaces and vegetation, etc.). We refer to these results as 'low-hanging fruit'. If the discipline of urban ecology is going to provide the necessary information to inform actions to preserve and enhance urban biodiversity, we need to move beyond place-based research, and work towards the development of confirmed generalizations regarding the relationship between the structure and function of urban ecosystems and biodiversity. We propose three essential strategies for achieving this refined understanding: 1) defining the study window to place the study into a broader global context, 2) collecting and using more explicit question-driven measures of the urban condition in order to improve our understanding of urban ecological drivers, as well as recording more detailed ecological responses to provide insights into the ecological mechanisms underlying an observed response, and 3) expanding studies to include multiple cities, regions and countries. These strategies will help to expedite the ability of urban ecology to contribute to the creation of biodiversity-rich, healthy, resilient cities and towns. [ABSTRACT FROM AUTHOR]