House Sparrows as Sentinels of Childhood Lead Exposure.

Our understanding of connections between human and animal health has advanced substantially since the canary was introduced as a sentinel of toxic conditions in coal mines. Nonetheless, the development of wildlife sentinels for monitoring human exposure to toxins has been limited. Here, we capitalized on a three-decade long child blood lead monitoring program to demonstrate that the globally ubiquitous and human commensal house sparrow (Passer domesticus) can be used as a sentinel of human health risks in urban environments impacted by lead mining. We showed that sparrows are a viable proxy for the measurement of blood lead levels in children at a neighborhood scale (0.28 km2). In support of the generalizability of this approach, the blood lead relationship established in our focal mining city enabled us to accurately predict elevated blood lead levels in children from another mining city using only sparrows from the second location. Using lead concentrations and lead isotopic compositions from environmental and biological matrices, we identified shared sources and pathways of lead exposure in sparrows and children, with strong links to contamination from local mining emissions. Our findings showed how human commensal species can be used to identify and predict human health risks over time and space.

Blood lead increases and haemoglobin decreases in urban birds along a soil contamination gradient in a mining city.

Lead contaminated soil is a persistent global threat to the health of animal populations. Nevertheless, links between soil lead and its adverse effects on exposed wildlife remain poorly understood. Here, we explore local geographic patterns of exposure in urban birds along a gradient of lead contamination in Broken Hill, an Australian mining city. Soil lead concentrations are linked to co-located blood lead measurements in rock pigeons (Columba livia), house sparrows (Passer domesticus), crested pigeons (Ocyphaps lophotes) and white-plumed honeyeaters (Lichenostomus ornatus). Median blood lead levels were highest in crested pigeons (59.6 µg/dL), followed by house sparrows (35.2 µg/dL), rock pigeons (35.1 µg/dL), and white-plumed honeyeaters (27.4 µg/dL). Blood lead levels in all species declined away from mining areas, the primary source of lead contamination in Broken Hill. Blood lead increased significantly and at the greatest rate relative to soil lead in the three ground foraging species (crested pigeons, house sparrows, rock pigeons). For these species, soil lead concentrations below 200 mg/kg and 900 mg/kg were needed to maintain a median blood lead concentration under the lower threshold of the subtoxic (20-50 µg/dL) and toxic (≥50 µg/dL) effect ranges previously identified for some bird species. We also investigated the effects of lead exposure on blood haemoglobin levels as a general measure of physiological condition in birds exposed to different levels of soil lead contamination. Overall, for every 1 µg/dL increase in blood lead, haemoglobin decreased by 0.11 g/L. The rate of this decrease was not significantly different between species, which supports the measurement of haemoglobin as a consistent though insensitive measure of physiological condition in chronically lead exposed birds. Our findings reflect the importance of lead contaminated soil as a widespread source of elevated blood lead and supressed haemoglobin levels in birds inhabiting urbanised and mining impacted environments.

Vegetation complexity and nesting resource availability predict bee diversity and functional traits in community gardens.

Urban gardens can support diverse bee communities through resource provision in resource poor environments. Yet the effects of local habitat and landscape factors on wild bee communities in cities is still insufficiently understood, nor is how this information could be applied to urban wildlife conservation. Here we investigate how taxonomic and functional diversity of wild bees and their traits in urban community gardens are related to garden factors and surrounding landscape factors (e.g., plant diversity, amount of bare ground, amount of nesting resources, amount of landscape imperviousness). Using active and passive methods in 18 community gardens in Berlin, Germany, we documented 26 genera and 102 species of bees. We found that higher plant species richness and plant diversity as well as higher amounts of deadwood in gardens leads to higher numbers of wild bee species and bee (functional) diversity. Furthermore, higher landscape imperviousness surrounding gardens correlates with more cavity nesting bees, whereas a higher amount of bare ground correlates with more ground-nesting bees. Pollen specialization was positively associated with plant diversity, but no factors strongly predicted the proportion of endangered bees. Our results suggest that, aside from foraging resources, nesting resources should be implemented in management for more pollinator-friendly gardens. If designed and managed using such evidence-based strategies, urban gardens can create valuable foraging and nesting habitats for taxonomically and functionally diverse bee communities in cities.

Urban Microplastic Pollution Revealed by a Large-Scale Wetland Soil Survey.

Microplastics (MPs), as a new persistent pollutant, can be emitted and accumulated in urban environments, but there is no detailed information on the driving factors of MP pollution. In this study, through a large-scale wetland soil survey, the features of MPs were characterized in each urban area. The results showed an average abundance to be 379 n/kg in wetland soil. Polypropylene, fiber or fragment, and black color were common composition, shape, and color, respectively. The spatial distribution information showed that MP abundance was significantly relevant to the distance from the urban economic center. Furthermore, the correlation and regression analysis revealed that MP abundance was related to soil heavy metal and atmospheric particle (PM10 and PM2.5) concentrations (P < 0.05), while the promotion of socioeconomic activities (urbanization level, population density, etc.) may aggravate the pollution degree. Additionally, by using structural equation modeling, it was found that the urbanization level was the dominant factor driving the MP pollution degree, with a total effect coefficient of 0.49. Overall, this work provides multi-sided environmental information regarding MP pollution in urban ecosystems, which is significant for follow-up studies of MP pollution control and restoration.

Neonicotinoids and pharmaceuticals in hair of the Red fox (Vulpes vulpes) from the Cavallino-Treporti peninsula, Italy.

Neonicotinoids (NEOs) and active pharmaceuticals ingredients (API) are contaminants widely diffused worldwide, causing increasing concern for potential adverse effects on wildlife. However, research on these contaminants have focused on target and non-target invertebrates, while information on potential effects in terrestrial mammals is lacking. We performed preliminary non-invasive monitoring of NEOs and API in a suburban and agricultural area using hair of the Red fox. The Red fox is a widely diffused mesopredator in Europe, and its plasticity in feeding habits makes it an excellent indicator for assessing exposure to environmental contamination. We observed the presence of NEOs in many Red fox hair samples (n = 11), including imidacloprid (IMI), acetamiprid (ACE), and clothianidin (CLO). The highest quantified concentrations were 6.4 ng g-1 dry weight (dw), 6.7 ng g-1 dw, and 0.9 ng g-1 dw for IMI, ACE, and CLO, respectively. The targeted APIs included non-steroidal anti-inflammatory drugs (NSAIDs) and antidepressants. APIs were less frequently detected than NEOs, and the compounds with the highest prevalence were the NSAID ketoprofen (36%), the antidepressant sertraline (36%), and its active metabolite norsertraline (27%). The presence of human pharmaceuticals such as the NSAID ibuprofen and the antidepressants sertraline, fluoxetine, and their active metabolites norsertraline and norfluoxetine suggest environmental contamination due to untreated and partially treated wastewater discharged in surface waters and soils of the study area. The detection and quantification of ketoprofen and flunixin also suggest the possible use of contaminated manure on farmland. Findings indicate that hair may be used for monitoring environmental exposure to NEOs and provide evidence that hair is a good marker of exposure for antidepressants and certain NSAIDs, including ibuprofen, ketoprofen, and flunixin.

Higher diversity, denser stands and greater biomass in peri-urban forests than in adjacent agroforestry systems in Western Burkina Faso: implications for urban sustainability.

Urban and peri-urban forests greatly contribute to the well-being of urban dwellers in West Africa. However, increasing urban densification and spatial expansion negatively affect the functioning of urban ecosystems. Therefore, highlighting the negative impacts of land use change on the ecological attributes of urban landscapes is fundamental for sustainable urban planning. This study aimed to assess the impacts of land use on woody species diversity, structure and carbon storage in peri-urban areas in Burkina Faso. Forest inventories were conducted in 167 plots across two peri-urban forests and their adjacent agroforestry systems. We found a total diversity of 91 woody species representing 69 genera and 26 families. Diversity indices were significantly higher (p-value < 0.0001) in the peri-urban forests than in the agroforestry systems, highlighting a negative impacts of land use on tree diversity. Besides, peri-urban forests had significantly lower tree diameter (15.749 ± 9.194 cm), but higher basal area (5.030 ± 4.407 m2. ha-1) and denser stands (317.308 ± 307.845 ind. ha-1) compared to the agroforestry systems. Tree aboveground biomass was significantly higher (p-value < 0.0001) in the peri-urban forests (18.198 ± 23.870 Mg. ha-1) than in the agroforestry systems (7.821 ± 6.544 Mg. ha-1). Multivariate analyses revealed that denser stands hold higher diversity in peri-urban areas, and that stand basal area mostly drives carbon storage than tree density and diversity. These findings highlight the potential of peri-urban forests to conserve plant biodiversity and mitigate climate change. The study advocates for a sustainable urban land use and planning.

Effect of urbanization and its environmental stressors on the intraspecific variation of flight functional traits in two bumblebee species.

The way urbanization shapes the intraspecific variation of pollinator functional traits is little understood. However, this topic is relevant for investigating ecosystem services and pollinator health. Here, we studied how urbanization affects the functional traits of workers in two bumblebee species (Bombus terrestris and B. pascuorum) sampled in 37 sites along a gradient of urbanization in North Italy (an area of 1800 km2 including the metropolitan context of Milan and other surrounding capital districts). Namely, we investigated the effect of land use composition, configuration, air temperature, flower resource abundance, and air pollutants on the variation of traits related to flight performance and of stress during insect development (i.e., wing size, wing shape and size fluctuating asymmetry). The functional traits of the two bumblebees responded idiosyncratically to urbanization. Urban temperatures were associated with smaller wing sizes in B. pascuorum and with more accentuated fluctuating asymmetry of wing size in B. terrestris. Moreover, flower abundance correlated with bigger wings in B. terrestris and with less asymmetric wing size in B. pascuorum. Other traits did not vary significantly, and other urban variables played minor effects. These species-specific variation patterns highlight that environmental stressor linked to urbanization negatively impact the traits related to flight performance and development stability of these syntopic bumblebees, with possible consequences on the pollination service they provide.

Feasibility study for estimating optimal substrate parameters for sustainable green roof in Sri Lanka.

In twenty-first century buildings, green roof systems are envisioned as great solution for improving Environmental sustainability in urban ecosystems and it helps to mitigate various health hazards for humans due to climatic pollution. This study determines the feasibility of using five domestic organic wastes, including sawdust, wood bark, biochar, coir, and compost, as sustainable substrates for green roofs as compared to classical Sri Lankan base medium (fertiliser + potting mix) in terms of physicochemical and biological parameters associated with growing mediums. Comprehensive methodologies were devised to determine the thermal conductivity and electric conductivity of growing mediums. According to preliminary experimental results, the most suitable composition for green roof substrates comprised 60% organic waste and 40% base medium. Sawdust growing medium exhibited the highest moisture content and minimum density magnitudes. Biochar substrate was the best performing medium with the highest drought resistance and vegetation growth. The wood bark substrate had the highest thermal resistance. Growing mediums based on compost, sawdust, and coir produced the best results in terms of nitrate, phosphate, pH, and electric conductivity (EC) existence. This study provided a standard set of comprehensive comparison methodologies utilising physicochemical and biological properties required for substrate characterization. The findings of this research work have strong potential in the future to be used in selecting the most suitable lightweight growing medium for a green roof based on stakeholder requirements.

Opportunistic Mycobiota of Dust in Cities of Different Climate Zones: Murmansk and Moscow.

For the first time, mycological analysis of dust, including assessment of opportunistic fungal species, was carried out for the urban ecosystems of air, vegetation, and paved surfaces in different climate areas (the cities of Murmansk and Moscow). The combined effect of environmental factors (climate, functional zone, and substrate type) on qualitative and quantitative parameters of micromycete communities was assessed using MANOVA and cluster analysis. It was found that the abundance of culturable mycobiota in the air, on tree leaves, and on paved surfaces was lower in Murmansk than in Moscow. In both cities, approximately a half of fungal species were opportunistic pathogens. The relative abundance of opportunistic fungi of the BSL-2 group was higher in the air of the traffic zone in both cities and of the residential zone in Moscow. In the residential and traffic zones of Moscow, the most abundant species in the air in on the road dust were Aspergillus fumigatus and A. niger, while in Murmansk communities were dominated by members of the genera Cephalosporium, Scopulariopsis, and Trichoderma, which are less pathogenic for humans. The most significant factors affecting the abundance and species diversity of micromycetes, including opportunistic fungi, were the substrate type (air, leaves, or paved surfaces) and the climate, while the effect of the functional zone was not significant. The recreation zones of cities located in different climate regions are the most favorable for humans due to lower abundance of opportunistic fungi in the air and to lack of micromycetes of the BSL-2 and BSL-3 groups. However, the abundance of potentially pathogenic species on the surfaces of leaves and roads in this zone was higher than in the air. Therefore, it can be recommended that city residents minimize their contact with the leaves surface and road pavements, which is especially relevant for toddlers, so as to diminish the probability of encountering opportunistic mycobiota that potentially represents a health hazard.

Bioaerosols in urban environments: Trends and interactions with pollutants and meteorological variables based on quasi-climatological series.

Pollen grains emitted by urban vegetation are the main primary biological airborne particles (PBAPs) which alter the biological quality of urban air and have a significant impact on human health. This work analyses the interactions which exist between pollen-type PBAPs, meteorological variables, and air pollutants in the urban atmosphere so that the complex relationships and trends in future scenarios of changing environmental conditions can be assessed. For this study, the 1992-2018 pollen data series from the city of Granada (southeast Spain) was used, in which the dynamics of the total pollen as well as the 8 main pollen types (Cupressaceae, Olea, Pinus, Platanus, Poaceae, Populus, Quercus and Urticaceae) were analysed. The trend analysis showed that all except Urticaceae trended upward throughout the series. Spearman's correlations with meteorological variables showed that, in general, the most influential variables on the pollen concentrations were the daily maximum temperature, relative humidity, water vapor pressure, global radiation, and insolation, with different effects on different pollen types. Parallel analysis by neural networks (ANN) confirmed these variables as the predominant ones, especially global radiation. The correlation with atmospheric pollutants revealed that ozone was the pollutant with the highest influence, although some pollen types also showed correlation with NO2, SO2, CO and PM10. The Generalized Linear Models (GLM) between pollen and pollutants also indicated O3 as the most prominent variable. These results highlight the active role that pollen-type PBAPs have on urban air quality by establishing their interactions with meteorological variables and pollutants, thereby providing information on the behaviour of pollen emissions under changing environmental conditions.

Nests in the cities: adaptive and non-adaptive phenotypic plasticity and convergence in an urban bird.

Phenotypic plasticity plays a critical role in adaptation to novel environments. Behavioural plasticity enables more rapid responses to unfamiliar conditions than evolution by natural selection. Urban ecosystems are one such novel environment in which behavioural plasticity has been documented. However, whether such plasticity is adaptive, and if plasticity is convergent among urban populations, is poorly understood. We studied the nesting biology of an 'urban-adapter' species, the dark-eyed junco (Junco hyemalis), to understand the role of plasticity in adapting to city life. We examined (i) whether novel nesting behaviours are adaptive, (ii) whether pairs modify nest characteristics in response to prior outcomes, and (iii) whether two urban populations exhibit similar nesting behaviour. We monitored 170 junco nests in urban Los Angeles and compared our results with prior research on 579 nests from urban San Diego. We found that nests placed in ecologically novel locations (off-ground and on artificial surfaces) increased fitness, and that pairs practiced informed re-nesting in site selection. The Los Angeles population more frequently nested off-ground than the San Diego population and exhibited a higher success rate. Our findings suggest that plasticity facilitates adaptation to urban environments, and that the drivers behind novel nesting behaviours are complex and multifaceted.

Gridlock and beltways: the genetic context of urban invasions.

The rapid expansion of urban land across the globe presents new and numerous opportunities for invasive species to spread and flourish. Ecologists historically rejected urban ecosystems as important environments for ecology and evolution research but are beginning to recognize the importance of these systems in shaping the biology of invasion. Urbanization can aid the introduction, establishment, and spread of invaders, and these processes have substantial consequences on native species and ecosystems. Therefore, it is valuable to understand how urban areas influence populations at all stages in the invasion process. Population genetic tools are essential to explore the driving forces of invasive species dispersal, connectivity, and adaptation within cities. In this review, we synthesize current research about the influence of urban landscapes on invasion genetics dynamics. We conclude that urban areas are not only points of entry for many invasive species, they also facilitate population establishment, are pools for genetic diversity, and provide corridors for further spread both within and out of cities. We recommend the continued use of genetic studies to inform invasive species management and to understand the underlying ecological and evolutionary processes governing successful invasion.

Travel cost analysis of an urban protected area and parks in Singapore: a mobile phone data application.

Big data have the potential to improve nonmarket valuation, but their application has been scarce. To test this potential, we apply mobile phone data to the zonal travel cost method and measure recreational ecosystem services from Bukit Timah (representing an urban protected area) and Jurong Lake Gardens (an urban recreational park) in Singapore. The study results show that the annual recreational benefits of the recreational park (S$54,698,761 to S$66,805,454) outweighed the benefits of the protected area (S$6,947,974 to S$9,068,027). The count data structure reduced the flexibility of the mobile phone data application. Compared to survey data, however, mobile phone data could prevent random errors and visitor memory biases; monitor impacts of site quality changes over time; count visitors from multiple entrances; and be cost-efficient. Overall, these results highlight the potential of mobile phone data application to improve travel cost analysis.

Greenhouse Gas Fluxes of Mangrove Soils and Adjacent Coastal Waters in an Urban, Subtropical Estuary.

Mangroves are known to sequester carbon at rates exceeding even those of other tropical forests; however, to understand carbon cycling in these systems, soil-atmosphere fluxes and gas exchanges in mangrove-adjacent shallow waters need to be quantified. Further, despite the ever-increasing impact of development on mangrove systems, there is even less data on how subtropical, greenhouse gas (GHG) fluxes are affected by urbanization. We quantified carbon dioxide (CO2) and methane (CH4) fluxes from mangrove soils and adjacent, coastal waters along a gradient of urbanization in the densely-populated, subtropical San Juan Bay Estuary (PR). Edaphic (salinity, pH, surface temperature) factors among sites significantly covaried with GHG fluxes. We found that mangrove systems in more highly-urbanized reaches of the estuary were characterized by relatively lower porewater salinities and substantially larger GHG emissions, particularly CH4, which has a high global warming potential. The magnitude of the CO2 emissions was similar in the mangrove soils and adjacent waters, but the CH4 emissions in the adjacent waters were an order of magnitude higher than in the soils and showed a marked response to urbanization. This study underscores the importance of considering GHG emissions of adjacent waters in carbon cycling dynamics in urbanized, tropical mangrove systems.

Valuing urban green spaces in mitigating climate change: A city-wide estimate of aboveground carbon stored in urban green spaces of China's Capital.

Urban green spaces provide manifold environmental benefits and promote human well-being. Unfortunately, these services are largely undervalued, and the potential of urban areas themselves to mitigate future climate change has received little attention. In this study, we quantified and mapped city-wide aboveground carbon storage of urban green spaces in China's capital, Beijing, using field survey data of diameter at breast height (DBH) and tree height from 326 field survey plots, combined with satellite-derived vegetation index at a fine resolution of 6 m. We estimated the total amount of carbon stored in the urban green spaces to be 956.3 Gg (1 Gg = 109 g) in 2014. There existed great spatial heterogeneity in vegetation carbon density varying from 0 to 68.1 Mg C ha-1 , with an average density of 7.8 Mg C ha-1 . As expected, carbon density tended to decrease with urban development intensity (UDI). Likely being affected by vegetation cover proportion and configuration of green space patches, large differences were presented between the 95th and 5th quantile carbon density for each UDI bin, showing great potential for carbon sequestration. However, the interquartile range of carbon density narrowed drastically when UDI reached 60%, signifying a threshold for greatly reduced carbon sequestration potentials for higher UDI. These findings suggested that urban green spaces have great potential to make contribution to mitigating against future climate change if we plan and design urban green spaces following the trajectory of high carbon density, but we should be aware that such potential will be very limited when the urban development reaches certain intensity threshold.

Current and historical land use influence soil-based ecosystem services in an urban landscape.

Urban landscapes are increasingly recognized as providing important ecosystem services (ES) to their occupants. Yet, urban ES assessments often ignore the complex spatial heterogeneity and land-use history of cities. Soil-based services may be particularly susceptible to land-use legacy effects. We studied indicators of three soil-based ES, carbon storage, water quality regulation, and runoff regulation, in a historically agricultural urban landscape and asked (1) How do ES indicators vary with contemporary land cover and time since development? (2) Do ES indicators vary primarily among land-cover classes, within land-cover classes, or within sites? (3) What is the relative contribution of urban land-cover classes to potential citywide ES provision? We measured biophysical indicators (soil carbon [C], available phosphorus [P], and saturated hydraulic conductivity [Ks ]) in 100 sites across five land-cover classes, spanning an ~125-year gradient of time since development within each land-cover class. Potential for ES provision was substantial in urban green spaces, including developed land. Runoff regulation services (high Ks ) were highest in forests; water quality regulation (low P) was highest in open spaces and grasslands; and open spaces and developed land (e.g., residential yards) had the highest C storage. In developed land covers, both C and P increased with time since development, indicating effects of historical land-use on contemporary ES and trade-offs between two important ES. Among-site differences accounted for a high proportion of variance in soil properties in forests, grasslands, and open space, while residential areas had high within-site variability, underscoring the leverage city residents have to improve urban ES provision. Developed land covers contributed most ES supply at the citywide scale, even after accounting for potential impacts of impervious surfaces. Considering the full mosaic of urban green space and its history is needed to estimate the kinds and magnitude of ES provided in cities, and to augment regional ES assessments that often ignore or underestimate urban ES supply.

Contemporary evolution and scaling of 32 major cities in China.

Most of the planet's population currently lives in urban areas, and urban land expansion is one of the most dramatic forms of land conversion. Understanding how cities evolve temporally, spatially, and organizationally in a rapidly urbanizing world is critical for sustainable development. However, few studies have examined the coevolution of urban attributes in time and space simultaneously and the adequacy of power law scaling across cities and through time, particularly in countries that have experienced abrupt, widespread, political and economic changes. Here, we show the temporal coevolution of multiple physical, demographic, socioeconomic, and environmental attributes in individual cities, and the cross-city scaling of urban attributes at six time points (i.e., 1978, 1990, 1995, 2000, 2005, and 2010) in 32 major Chinese cities. We found that power law scaling could adequately characterize both the cross-city scaling of urban attributes across cities and the longitudinal scaling describing the temporal coevolution of urban attributes within individual cities. The cross-city scaling properties demonstrated substantial changes over time signifying evolved social and economic forces. A key finding was that the cross-city linear or superlinear scaling of urban area with population contradicts the theoretical sublinear power law scaling proposed between infrastructure and population. Furthermore, the cross-city scaling between area and population transitioned from linear to superlinear over time, and the superlinear scaling in recent times suggests decreased infrastructure efficiency. Our results demonstrate a diseconomy of scale in urban areal expansion that indicates a significant waste of land resources in the urbanization process. Future planning efforts should focus on policies that increase urban land use efficiency before continuing expansion.

Nature-based solutions for resilient landscapes and cities.

Nature-based solutions (NBS) are increasingly applied to guide the design of resilient landscapes and cities to enable them to reach economic development goals with beneficial outcomes for the environment and society. The NBS concept is closely related to other concepts including sustainability, resilience, ecosystem services, coupled human and environment, and green (blue) infrastructure; however, NBS represent a more efficient and cost-effective approach to development than traditional approaches. The European Commission is actively engaged in investing in NBS as a driver in developing ecosystem services-based approaches throughout Europe and the world. The pool of knowledge and expertise presented in this Special Issue of Environmental Research highlights the applications of NBS as 'living' and adaptable tools to boost the capacity of landscapes and cities to face today's critical environmental, economic and societal challenges. Based on the literature and papers of this Special Issue, we propose five specific challenges for the future of NBS.

Fox sightings in a city are related to certain land use classes and sociodemographics: results from a citizen science project.

BACKGROUND: Red foxes (Vulpes vulpes L.) have become successful inhabitants of urban areas in recent years. However, our knowledge about the occurrence, distribution and association with land uses of these urban foxes is poor, partly because many favoured habitats are on private properties and therefore hardly accessible to scientists. We assumed that citizen science, i.e. the involvement of the public, could enable researchers to bridge this information gap. We analysed 1179 fox sightings in the city of Vienna, Austria reported via citizen science projects to examine relationships between foxes and the surrounding land use classes as well as sociodemographic parameters. RESULTS: Conditional probabilities of encountering foxes were substantially higher in gardens, areas with a low building density, parks or squares as compared to agricultural areas, industrial areas or forests. Generalized linear model analyses showed that sociodemographic parameters such as education levels, district area, population density and average household income additionally improved the predictability of fox sightings. CONCLUSIONS: Reports of fox sightings by citizen scientists might help to support the establishment of wildlife management in cities. Additionally, these data could be used to address public health issues in relation with red foxes as they can carry zoonoses that are also dangerous to humans.

Managing Urban Plant Invasions: a Multi-Criteria Prioritization Approach.

Alien plant invasions in urban areas can have considerable impact on biodiversity and ecosystem services (ES). Managing urban plant invasions is particularly challenging given the complex interactions between ecological, economic and social elements that exist in the urban milieu. Strategic landscape-scale insights are crucial for guiding management, as are tactical site-scale perspectives to plan and coordinate control efforts on the ground. Integrating these requirements to enhance management efficiency is a major challenge. Decision-support models have considerable potential for guiding and informing management strategies when problems are complex. This study uses multi-criteria decision tools to develop a prioritization framework for managing invasive alien plants (IAPs) in urban areas at landscape and local scales. We used the Analytic Hierarchy Process (AHP; a multi-criteria decision support model) to develop and rank criteria for prioritising IAP management in the City of Cape Town (CoCT), South Africa. Located within a global biodiversity hotspot, Cape Town has a long history of alien plant introductions and a complex socio-political make-up, creating a useful system to explore the challenges associated with managing urban plant invasions. To guide the prioritization of areas for IAP management across the CoCT, a stakeholder workshop was held to identify a goal and criteria for consideration, and to assess the relative importance given to each criterion in IAP management. Workshop attendees were drawn from multiple disciplines involved with different aspects of IAP research and management: government departments, scientists and researchers, and managers with a diverse set of skills and interests. We selected spatial datasets and applied our multi-criteria decision analysis in a Geographic Information System (GIS) to develop a landscape-scale prioritization map. To address issues relevant in an urban setting, we also modified an existing IAP management framework to develop a tactical (site-level) prioritization scheme for guiding on-the-ground control operations. High-priority sites for IAP management were identified at landscape- and local scales across the study area. Factors related to safety and security emerged as pivotal features for setting spatially-explicit priorities for management. The approach applied in this study can be useful for managers in all urban settings to guide the selection and prioritization of areas for IAP management.