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Cities can host significant biological diversity. Yet, urbanisation leads to the loss of habitats and, potentially, to local extinctions. Understanding how multiple taxa respond to urbanisation globally is essential to promote and conserve biodiversity in cities and surrounding landscapes. Using a dataset with site-level occurrence and trait data of 5302 species from six terrestrial fauna taxonomic groups across 379 cities on 6 continents, we show that urbanisation produces taxon-specific changes in trait composition, with traits related to reproductive strategy consistently showing the strongest response. The effect of urbanisation on community trait composition is strongest at the largest spatial scale considered, and more closely linked to landscape composition (% urban) than arrangement (aggregation), although latitude and climatic variables remain a stronger influence. This study did not find evidence in support of a global urban taxa syndrome, but instead we suggest that there are four general urban trait syndromes, with resources associated with reproduction and diet likely to be driving patterns in traits associated with mobility and body size. Functional diversity measures showed a wide range of responses, leading to a shift in trait space that is most likely driven by the distribution and abundance of critical resources, and the urban trait syndrome displayed by individual species within a community. Further research is required to understand the interactions between the four general urban trait syndromes, resource distribution and abundance and changes in functional diversity of taxa at different spatial and temporal scales. Maximising opportunities to support species within taxa groups with different urban trait syndromes should be pivotal in conservation and management programmes within and among cities. This will reduce the likelihood of biotic homogenisation at the taxa level, and helps ensure that urban environments have the ecological capacity to respond to challenges such as climate change, further habitat fragmentation and loss, and other disruptions. These actions are critical if we are to reframe the role of cities in global biodiversity loss.

Societal Impact Statement It is increasingly common for plant scientists and urban planning and design professionals to collaborate on interdisciplinary teams that integrate scientific experiments into public and social urban spaces. However, neither the procedural ethics that govern scientific experimentation, nor the professional ethics of urban design and planning practice, fully account for the possible impacts of urban ecological experiments on local residents and communities. Scientists that participate in design and planning teams act as decision‐makers, and must expand their domain of ethical consideration accordingly. Conversely, practitioners who engage in ecological experiments take on the moral responsibilities inherent in generation of knowledge. To avoid potential harm to human and non‐human inhabitants of cities while maintaining scientific and professional integrity in research and practice, an integrated ethical framework is needed for urban ecological planning and design. Summary While there are many ethical and procedural guidelines for scientists who wish to inform decision‐making and public policy, urban ecologists are increasingly embedded in planning and design teams to integrate scientific measurements and experiments into urban landscapes. These scientists are not just informing decision‐making – they are themselves acting as decision‐makers. As such, researchers take on additional moral obligations beyond scientific procedural ethics when designing and conducting ecological design and planning experiments. We describe the growing field of urban ecological design and planning and present a framework for expanding the ethical considerations of socioecological researchers and urban practitioners who collaborate on interdisciplinary teams. Drawing on existing ethical frameworks from a range of disciplines, we outline possible ways in which ecologists, social scientists, and practitioners should expand the traditional ethical considerations of their work to ensure that urban residents, communities, and non‐human entities are not harmed as researchers and practitioners carry out their individual obligations to clients, municipalities, and scientific practice. We present an integrated framework to aid in the development of ethical codes for research, practice, and education in integrated urban ecology, socioenvironmental sciences, and design and planning.

Planning for urban water conservation requires an understanding of how and where water is used in cities. There is significant evidence that urban water use is related to the characteristics of the residents, housing types, and landscaping patterns. At the same time, a growing body of research has shown geographic clustering of high or low water use at the neighborhood scale. This paper explores how the characteristics of neighborhoods influence water use at the parcel scale. We hypothesized that neighborhood characteristics influence water use through social dynamics as well as the physical structure of the neighborhood. Using a dataset for almost 75,000 parcels across 248 neighborhoods in Salt Lake City, Utah, we used multilevel modeling to determine how nine characteristics of neighborhoods influenced parcel-level water use. Almost a quarter (24%) of the variation in parcel-scale water use was explained by neighborhood characteristics. Controlling for key parcel-level drivers of water use, we determined that several neighborhood factors were significantly associated with parcel-level water use. For residential properties, parcels in more homogeneous suburban neighborhoods dominated by detached single family-owned homes and family households used more water than comparable parcels in neighborhoods with mixed housing and household types. Neighborhood effects were more pronounced for residential parcels than commercial, and more for outdoor than indoor water use. We suggest that planning and design strategies at the neighborhood level can contribute to urban water conservation.

Climate change and population growth serve as fundamental problems in assessing potential impacts on future surface water quality. In addition to uncertainties in climate depicted in various representative concentration pathway (RCP) scenarios, futuristic population growth mimicking historical conditions is subject to uncertainties related to changing development patterns. The combination of climate change and population characteristics exacerbates concerns regarding the future water quality performance of river systems. Previous studies have established linkages among future climate, population impacts and watershed water quality performance. However, these linkages have not been specifically incorporated into water quality trading programs. Rather than temporally-variant adjustment factors, WQT programs use constant margins of safety for pollutant reduction credits resulting in trade ratios that do not explicitly account for futuristic climate and population uncertainties. Hence, this study proposes a conceptual framework for water quality trading establishing adjustment factors as margins of safety on trade ratios for pollutant reduction credits examining climate and population characteristics separately followed by evaluating them combined. This new framework is demonstrated using a programming script that calculates the margins of safety based on simulation results conducted through a water quality model of the Jordan River in Salt Lake City, UT, USA over a 3-year timeframe. With margins of safety over magnitudes of ±2 over the Jordan River simulations, this research introduces the framework as a foundation for developing adjustment factors for addressing climatic and population characteristics upon river systems.

This study reports economic development outcomes—defined as change in employment—for areas within 0.25 mi of three streetcar stations along four lines in each of four cities: Portland OR; Salt Lake...

Urbanization, climate, and ecosystem change represent major challenges for managing water resources. Although water systems are complex, a need exists for a generalized representation of these systems to identify important components and linkages to guide scientific inquiry and aid water management. We developed an integrated Structure-Actor-Water framework (iSAW) to facilitate the understanding of and transitions to sustainable water systems. Our goal was to produce an interdisciplinary framework for water resources research that could address management challenges across scales (e.g., plot to region) and domains (e.g., water supply and quality, transitioning, and urban landscapes). The framework was designed to be generalizable across all human–environment systems, yet with sufficient detail and flexibility to be customized to specific cases. iSAW includes three major components: structure (natural, built, and social), actors (individual and organizational), and water (quality and quantity). Key linkages among these components include: (1) ecological/hydrologic processes, (2) ecosystem/geomorphic feedbacks, (3) planning, design, and policy, (4) perceptions, information, and experience, (5) resource access and risk, and (6) operational water use and management. We illustrate the flexibility and utility of the iSAW framework by applying it to two research and management problems: understanding urban water supply and demand in a changing climate and expanding use of green storm water infrastructure in a semi-arid environment. The applications demonstrate that a generalized conceptual model can identify important components and linkages in complex and diverse water systems and facilitate communication about those systems among researchers from diverse disciplines.

Wild pollinators provide important services to both wild and human-dominated ecosystems, yet this group may be threatened by widespread anthropogenic landscape change. Suburban sprawl is one of the fastest growing types of land use change in North America, and it has certain characteristics, such as abundant floral resources, that may be beneficial for many pollinators. We examined the effects of sprawl on the wild bee assemblage of the shortgrass steppe on the Front Range of Colorado, USA. Diversity, abundance, and community composition of bees in remnant grassland fragments surrounded by suburban residential land use were compared with those in extensive, continuous grassland. No overall effect of suburbanization on bee abundance was observed, and abundance was extremely variable even within study sites. Bee species richness was positively but nonlinearly related to grassland habitat area. Bee species density was higher and more variable in suburban sites. Suburban sites and smaller habitat area were both related to relative increases in the proportions of small bee species, social bees, and solitary cavity-nesting bees in the assemblage; small suburban habitat areas also favored species of the family Halictidae over Apidae, and individuals of the genus Halictus over those of the genus Lasioglossum. In this landscape, large native habitat areas surrounded by suburban sprawl may actually increase species richness and species density over that of continuous grassland, probably by means of habitat complementation or supplementation between grassland remnants and the surrounding suburban matrix. However, at habitat areas20 ha, species richness became quite variable; sites8 ha contained less than half the species of controls.

Wild pollinators provide important services in both wild and human-dominated ecosystems, yet this group may be threatened by widespread anthropogenic landscape change. We explored the responses of wild bees to exotic floral species and novel habitat in a fragmented, suburban landscape using pollen grain identification. Pollen loads from bee specimens collected in 13 suburban grassland fragments in Denver, Colorado were sampled and compared with a pollen reference collection. Averaged across two seasonal sampling rounds, 45% of the bee-borne pollen grains were identified to the species level. Wild bees in this system were very receptive to using alien plants for pollen foraging; at least 45% of pollen sampled from bee specimens consisted of non-native pollen grains. During peak flowering in early summer, bees obtained at least 32% of their pollen resources from within-fragment sources and at least 7.5% from surrounding suburban residential yards. In midsummer, within-fragment sources represented 58% of pollen sampled while yards dropped to 1.5%. These bees appear to be more accepting of exotic floral species than of exotic habitat types (yards). The advantages and disadvantages of pollen load analysis for movement studies are discussed.