Using best available science to protect critical areas in Washington state: challenges and barriers to planners

Urban development has profound impacts on ecological patterns and processes making the scientific information required for developing environmental ordinances central for mitigating these negative ecological impacts. Washington State requires that planners use the best available science (BAS) to formulate land use ordinances as part of the state’s Growth Management Act (GMA). We present empirical findings describing challenges to planners in defining “best available science” and using BAS to create local ordinances that balance development needs with natural resource protection. We interviewed city and county planners (and their consultants) in western Washington to determine what they find useful about BAS, whether or not BAS is applicable to their jurisdictions, and what constraints they experience in reviewing and using BAS to create or update their land use ordinances. Our results suggest that applying the BAS requirement is particularly difficult in urban areas. Specifically, planners had difficulty applying results from research conducted in systems dissimilar to their urban landscapes. These challenges to planners were exacerbated by (1) a lack of resources and (2) political tensions among stakeholders with competing values in urban settings. We conclude with recommendations for improving the consideration of science in statewide land-use planning.     

The future of urban biodiversity research: Moving beyond the ‘low-hanging fruit’

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.     

Engaging urban nature: improving our understanding of public perceptions of the role of biodiversity in cities

In recognition of the value of biodiversity for cities and citizens, a number of international programs have been designed to help municipal governments sustain, protect, and augment the biodiversity and ecosystem services within their jurisdictions. A key component of these programs is public engagement, where citizens assume a more active role in maintaining urban biodiversity and associated ecosystem services. Yet, there are few studies which have as their focus public knowledge of the importance of nature, biodiversity, and ecosystem services in cities. To these ends, this study was conducted to develop a better understanding of how the public understands and interacts with urban biodiversity, particularly in comparison to subject matter experts. Using topics generated from expert interviews and the literature, an interview guide was developed for the general public, structured around the general themes of a definition of urban biodiversity, as well as the perceived benefits, costs, and threats related to urban biodiversity. While there were similarities in the responses of citizens and experts, some differences did emerge in terms of accounting for specific urban ecosystems, acceptable interventions to support and enhance biodiversity, and the character and extent of the cultural services derived from urban nature. Insights from this work can be used to inform education and information efforts for the public, as well as raise awareness among city planners and nature professionals of the array of urban ecosystem services recognized and made use of by the public.

     

Assessing the structural heterogeneity of urban areas: an example from the Black Country (UK)

The increasing acknowledgement of the importance of urban habitats in the maintenance of biodiversity has brought with it a need to quantify this importance at a scale appropriate to the characteristic patch sizes encountered in urban areas. Taking a study area in the Black Country (UK) we used a spatially complete, rapid assessment method to evaluate habitat patches in terms of their internal structural heterogeneity. This method recognises the importance of both natural and anthropogenic processes in providing a diverse range of habitats and niches for both flora and fauna. It also recognises the key role of context in determining the ecological significance of each patch within the urban landscape.All habitats studied had a complex mix of both natural and artificial structural elements, where an element is a within-patch contributor to structural diversity, with each habitat type having a large range of element totals. Characteristic totals, reflecting the level of habitat structural diversity, were observed in some habitat types with residential areas having high values and industrial and commercial areas having low values. Certain structural elements were also associated with each habitat type allowing characteristic element assemblages to be derived. If structural diversity is linked with biodiversity, as seems to be the case in many (though not all) habitat types, then this unique method of viewing the urban landscape becomes a powerful tool for informing wildlife ecologists, nature conservationists, urban planners, environmental managers and landscape architects.     

Managing our urban future: the role of remote sensing and geographic information systems

Urban growth is inevitable over the next two decades. The bulk of this growth will take place in less developed countries. This presents a formidable challenge for urban planners and managers. With this in mind, this paper considers some of the ways urban planners can make use of recent developments in remote sensing and geographic information systems technology to respond to this challenge. The discussion is divided into four sections. The first of these considers the nature of the tasks involved. The second examines the potential of remote sensing and geographic information systems to assist in these tasks in general terms. The third section presents some of the findings of three case studies of contrasting application areas in the urban planning field which give some insights as to how these tools can be used to respond to this challenge. The final section rounds off the discussion with a vision of sustainable urban development and its implementation at the local level.     

Interdisciplinary research at the Urban–Rural interface: The West ga project

As human populations increase, ecological and social issues become inextricably linked to a greater degree. Solutions to complex social–ecological problems can only be derived through the use of integrated research that can account for the interplay of many factors across traditional discipline lines. We are using such an integrated research to clarify relationships among socioeconomic drivers, ecological effects, and social and policy feedbacks associated with urban development of forested landscapes. Our approach is goal oriented and interdisciplinary in nature and involves a team composed of ecologists, anthropologists, and economists who exchange ideas and information across disciplinary lines. The team and approach has evolved through many of the barriers to interdisciplinary research that have been identified by other authors. Our goal is to develop a predictive capability in order to anticipate ecological and social implications of urban development on natural resources in the southeastern United States. Our integrated model and subsequent papers in this special issue are presented.     

Bridging the gap between ecological research and land use policy: The North Sonoran Collaboration

A key factor in bridging the gap between ecological research and public land use policy is translating information from the language of research into the language of public policy making. Creating effective translations of research is often beyond the skills of urban planners and environmental researchers individually, and thus collaboration between the two is needed. Examples of such translation and partnerships can be found in the projects of an interdisciplinary group coined the North Sonoran Collaborative. This group consists of Phoenix, AZ, USA city staff, Arizona State University faculty, graduate students, and staff, and people from other local private companies and government agencies. The group, through its collaboration, has sponsored a series of environmental research efforts and translated those into successful land use planning activities and policies. The focus of the collaboration is the northern, largely undeveloped portion of the city of Phoenix, Arizona. This group has pursued three principles: desert ecosystems should be protected, a diversity of development should be pursued, and a sense of community should be created in new developments. This paper discusses this unique approach to planning and how it has proven effective in responding to the local communities needs quickly.     

A case study of urban ecological networks and a sustainable city: Tehran’s metropolitan area

The aim of this study is to propose the application of landscape ecology in planning urban ecological networks to conserve nature in urban landscapes and to develop a sustainable use of urban lands. Compared to the classical planning approach based on socio-economic land suitability, the principles of landscape ecology are helpful simultaneously conserving the ecological processes of landscapes and their steady changes. This approach could help in defining sustainable landscape development, aiming for a balance between both physical and natural systems in urban areas. This research is focused on the ecological networks in Tehran’s metropolitan area as a case study to provide a model for network planning in other urban areas, where urbanization seriously threats the natural environment. In concluding this research, the spatial structure and function of the area are studied and categorized based on the patch-corridor-matrix model. The paper concludes with methods of intervention and suggestions for the structural and functional improvement of urban landscapes towards achieving a more sustainable form of land use planning.     

Ecosystem services of urban green spaces in African countries—perspectives and challenges

The concept of ecosystem goods and services is increasingly used to describe how biodiversity and ecosystems are linked to human well-being and that it should be placed at the core of sustainable urban development. Predictions of a tremendous future increase of urbanization in Africa necessitate an investigation into the research on ecosystem goods and services in the urban green infrastructure of Africa. Ecosystem goods and services (ES) are described as the benefits humans derive directly or indirectly from ecosystem functions and are classified as supporting, provisioning, regulating and cultural services. A literature study focusing on journal papers was conducted. Additionally a case study based on two masters studies was further refined. ES studies in African cities are biased towards South Africa and include assessments and economic valuations in which several different methods were used to determine direct consumptive and non-consumptive and indirect use values. Emphasis was placed on the multifunctional nature of ES. The main objectives of these studies were to sensitize policy makers, planners and the general public about the importance of biodiversity and ES. Ecosystem-based adaptation is discussed as the most appropriate approach in terms of applying knowledge about ES and their values in African cities as many residents still rely on ES from natural areas, but the major ecological, economic and political challenges are acknowledged. A case study focusing on domestic gardens (private green spaces) have indicated that the demand and supply of certain ES differ along a socio-economic gradient due to poor service delivery and smaller plots in the poorer areas mainly due to the legacy of separate development of the past. Where provisioning services are mainly outsourced in cities, it was found that plant species useful as food, medicine, etc. were more frequent in the gardens of poorer residents than in those of more affluent areas. The tendency to pay more for residential properties close to public open spaces, as in Europe, could not be statistically proven in the more affluent areas of a South African city, although the property values in proximity of public open spaces in some of the areas studied were lower than further away.     

Assembling the pieces: a framework for the integration of multi-functional ecological main structure in the emerging urban region of Bogotá, Colombia

Bogotá, the capital of the Republic of Colombia, is a tropical highland city located 2,650 m above sea level. It is the 25th largest city in the world and, among large cities, is also one of the highest. In common with other cities in Latin America, a large part of its urban growth during recent centuries has been unplanned and informal. The introduction of green spaces into urban planning in Bogotá began in the mid-20th century, but was first included in official legislation during the 1990s through the concept of Ecological Main Structure (EMS). Initially developed by Dutch scholars, EMS was brought to Colombia via biological conservation practitioners as a means of enhancing biological connectivity in rural and natural landscapes, extended in this case to urban landscapes as a top-level planning instrument. EMS originally included a variety of components, from protected areas and biological conservation tools to environmental urban elements - the emphasis being on biodiversity conservation, without sufficient recognition of specific urban structures and functions. This process led to conceptual disciplinary-based divergence and conflicting political interpretations. The current emergence of EMS as a planning tool for urban regions represents an opportunity for integration, although the risk of divergent interpretations remains, as no integrative conceptual framework has yet been developed. In this paper we review the concepts underlying EMS that have been incorporated within urban and regional planning, especially those of ecological networks and green infrastructure, and also diagnose conceptual and institutional barriers to its current integration, challenges and opportunities which are set in the context of an emerging urban region. We propose a trans-disciplinary framework for multi-level integration of EMS, along a gradient from wild environments to built structures that incorporates emerging concepts such as urban biodiversity, ecosystem services and design in the urban landscape, with the aim of contributing to the creation of an urban landscape that is resilient to environmental change and suitable for human well-being and adaptation.     

Exploring structural habitat heterogeneity in sustainable urban drainage systems (SUDS) for urban biodiversity support

Implementation of sustainable urban drainage systems (SUDS) as part of cities’ transition towards climate resilience encompasses unique opportunities to enhance urban nature qualities. SUDS include individual elements integrated in the urban landscape, e.g. rain gardens or wet basins, which are usually constructed with low structural heterogeneity. Structural heterogeneity of habitats is, however, associated with a high degree of biodiversity. This study explored potentials of habitat heterogeneity enhancement in SUDS using structural heterogeneity as a proxy for biodiversity potential. In an interdisciplinary workshop, landscape architects and urban ecologists designed individual SUDS elements with enhanced structural habitat heterogeneity, hereafter bio-SUDS. The redesigned SUDS elements were infiltration trench, curb extension, rain garden, swale, wet basin, and dry basin. To evaluate the bio-SUDS designs, we developed an index of habitat heterogeneity in SUDS based on registration of 45 structurally important components. The conversion from standard SUDS to bio-SUDS entailed substantial increases in structural heterogeneity ranging from 4 to 18 additional components within elements. Larger bio-SUDS elements returned higher index scores, but the relative score increases were substantial for all bio-SUDS and in the range of a factor of 2–5.5. Increased terrain differences, meandering edges, stones, gravel, boulders, deadwood, and brown roof-like vegetation were the components most often employed in the bio-SUDS designs. In conclusion, implementation of bio-SUDS has potential to increase structural habitat heterogeneity thereby providing habitat for biodiversity in urban green areas. The developed bio-SUDS index can assist in future assessments of ecological qualities in designs and real-world SUDS elements.     

Urban ecosystems and sustainable urban development—analysing and assessing interacting systems in the Stockholm region

In order to build competence for sustainability analysis and assessment of urban systems, it is seen as essential to build on models representing urban form, landuse and transportation, urban metabolism, as well as ecological processes. This type of analysis of interacting sub-systems requires an advanced model integration platform, yet open for learning and for further development. Moreover, since the aim is to increase urban experience with ecosystem management in the wide sense, the platform needs to be open and easily available, with high visualisation capacity. For this purpose, the LEAM model was applied to the Stockholm Region and two potential future scenarios were developed, resulting from alternative policies. The scenarios differed widely and the dense urban development of Scenario Compact could be visualised, destroying much of the Greenstructure of Stockholm, while Scenario Urban Nature steered the development more to outer suburbs and some sprawl. For demonstration of the need for further development of biodiversity assessment models, a network model tied to a prioritised ecological profile was applied and altered by the scenarios. It could be shown that the Greenstructure did not support this profile very well. Thus, there is a need for dynamic models for negotiations, finding alternative solutions and interacting with other models. The LEAM Stockholm case study is planned to be further developed, to interact with more advanced transport and land use models, as well as analysing energy systems and urban water issues. This will enable integrated sustainability analysis and assessment of complex urban systems, for integration in the planning process in Stockholm as well as for comparative sustainability studies between different cities, with the goal to build more sustainable urban systems and to increase urban experiences in ecosystem management.     

Personal meaning in the public sphere: The standardisation and rationalisation of biodiversity data in the UK and the Netherlands

The demand for biodiversity data is increasing. Governments require standardised, objective data to underpin planning and conservation decisions. These data are produced by large numbers of (volunteer) natural historians and non-governmental organisations. This article analyses the interface between the state and the volunteer naturalists to understand the emerging patterns of information flow between them. Our results are based on research in the UK and the Netherlands. These two countries have a long history in volunteer biodiversity recording and are facing similar issues in relation to the increasing demand for standardised data. Our findings demonstrate that citizens who become involved in recording do so because they value nature and biodiversity. Recording is for them a way to enact their relationship with nature and contribute to its protection. Our findings also show that they are concerned about the increasing rationalisation in the process of data flow and about the way in which the government treats them and ‘their’ data. Our paper concludes by discussing this tension and the challenges and opportunities for biodiversity recording.     

A comparative gradient approach as a tool for understanding and managing urban ecosystems

To meet the grand challenges of the urban century??such as climate change, biodiversity loss, and persistent poverty??urban and ecological theory must contribute to integrated frameworks that treat social and ecological dynamics as interdependent. A socio-ecological framework that encapsulates theory from the social and ecological sciences will improve understanding of metropolitan dynamics and generate science for improved, sustainable management of urban ecosystems. To date, most urban ecological research has focused on single cities. A comparative approach that uses gradients within and between cities is a useful tool for building urban ecological theory. We offer five hypotheses that are testable using a comparative, gradient approach: (i) the current size, configuration, and function of larger metropolitan ecosystems predicts the potential trajectory of smaller urban areas; (ii) timing of growth explains the greatest variance in urban ecosystem structure and function; (iii) form and function of urban ecosystems are converging over time; (iv) urban ecosystems become more segregated and fragmented as populations increase; and (v) larger cities are more innovative than smaller cities in managing urban ecosystems.     

What about biodiversity? Redefining urban sustainable management to incorporate endemic fauna with particular reference to Australia

An estimated 50 % of the world’s population live in urban areas and this is expected to rise to 70 % by 2050. Urban developments will thus continue to encroach on non-urban landscapes and native biodiversity (flora and fauna). Although much has been written on sustainable urban development, the biodiversity component has been largely ignored. Consequently, sustainable development of biodiversity is poorly understood within urban confines by planners and designers, community developers and social planners, activists and social movements, and even academics and consultants. When native flora and fauna are incorporated deliberately or ad hoc, for example due to landscaping fashions, the outcome may create on-going issues for authorities which could be minimised with sustainable management. For example, green urban infrastructure including parks and gardens, ‘backyards’, remnant bushland and even wastelands can be more effectively developed to sustainably support biodiversity, typically at reduced on-going cost. However, due to the lack of understanding of this aspect of sustainable development and on-going issues of ‘pest management’, the focus has been on only a small sub-set of the overall biodiversity. In addition, these changes in species’ dynamics often lead to the decline of local amenity for humans, and endemic species (e.g., small-bodied birds). Other taxa are typically neglected because they are cryptic, innocuous, dangerous, a nuisance, feral, or just not ‘sexy’.     

Bird diversity of greenspaces in the densely developed city centre of Taipei

Urban greenspaces harbouring many species in cities are vital planning objects for enhancing biodiversity. Seeking to optimise ecological values of urban greenspaces, this paper explores 1. Bird composition by feeding and foraging characteristics in urban greenspaces located in densely developed central districts of Taipei City; and 2. Important features of greenspaces and underlying built environments that influence bird abundance, species richness, and diversity. Results show that the majority of birds found in the study sites are omnivorous and ground foragers; whereas birds relying on water/wetland habitats for feeding and foraging are relatively small in population and species richness. This suggests water/wetland associated environments and birds might be negatively impacted by urbanisation. Secondly, bird richness and diversity increase in accordance with greenspace size, water area, and habitat heterogeneity, but little relationship is found with greenspace structure, such as greenspace shape, distance to nearest greenspaces, and proximity to source patches of mountains and rivers. Also, no significant influence is observed from development intensity, which is measured by NDBI, and building height at greenspace surroundings. According to this result, this study suggests conservation of large greenspaces as a priority strategy for enhancing urban biodiversity. The development of land should take its potential ecological value into account while assessing environmental impact. For enhancing habitat quality of existing urban greenspaces, creating water bodies and increasing habitat types can be effective methods. Yet current planning strategies to increase street greenery and to connect urban greenspaces with surrounding mountains and rivers might only benefit specific urban exploiters or adaptors and result in little overall effect on richness and diversity.

     

Ecological lands for conservation of vascular plant diversity in the urban environment

Conservation of biodiversity in urban areas has become crucial to urban green area management. There are several legislative solutions for preservation of species and habitats in cities. One of them is ‘ecological lands’ – a low-restrictive form of protected areas in Poland. We aimed to assess their efficiency in vascular flora biodiversity conservation in the urban environment in Poznań (W Poland; 550,000 inhabitants). We hypothesized that ecological lands which cover <2% of the city area comprise over 50% of taxonomic diversity and over 90% of functional trait-level range of the vascular flora. Analysis of five ecological lands, which covered 1.8% of the whole city area confirmed our hypothesis. In ecological lands studied, we found 564 species of vascular plants, which is 52.9% of the whole city flora. These species belonged to 23 of 29 phytosociological classes represented in the whole city (73.9%). Functional trait distributions in ecological lands studied comprised from 95.8 to 100% of trait distributions in the flora of the whole city. Ecological lands seem to be a good way for conservation of biodiversity in urban areas. The legislative simplicity and low restrictiveness for both land management and recreational utility make ecological lands a much easier form of nature conservation which may be adapted to other cities for more efficient biodiversity management.     

Species richness in urban parks and its drivers: A review of empirical evidence

There is growing recognition of urban areas as hosts for innovative ways to conserve and promote biodiversity. Parks, as one specific type of urban green space, constitute particularly important biodiversity hotspots in the cityscape. We reviewed empirical findings on the species richness in urban parks across all species groups that have been studied. The aim was to assess and discuss the overall species richness of urban parks, its community attributes and drivers. Search and subsequent selection process resulted in 62 papers from 25 different countries. For all examined species groups, the findings consistently show that parks are among the most species rich types of urban green spaces, but also that exotics constitute large shares, especially of plant species. Key ecological theories like the gradient approach and the island habitat ecological theory, and fundamental ecological relationships such as the species-area relationship are valid despite the manipulated ‘nature’ of parks and the surrounding urban matrix. Most studies surveyed large number of parks and applied ‘multi-scale’ approaches in tests of confounding variables, providing methodological strength. While matrix effects are consistently found to affect species richness negatively, the diversity of habitats and microhabitat heterogeneity contained in urban parks appears as the most decisive factor for the overall species richness. However, a constraint of research to date is the limitation of individual studies to one or a few species groups, rarely bridging between flora and fauna. Adopting ‘multi-species group’ approaches in future research is needed to further advance the understanding of the overall biodiversity of urban parks, and its drivers.     

Biodiversity action plans as a way towards local sustainable development

Local action for biodiversity is essential to ensure better conservation status for biodiversity and maintain ecosystem services. In many places the rich biodiversity is still relatively untouched and represents an outstanding asset for local sustainable development. The loss of biodiversity occurs mainly because of rapid changes in land use, urban sprawl, infrastructure development, acidification, eutrophication, desertification, overexploitation, intensification of agriculture, tourism development and climate change. There is a clear need for a more flexible, people-oriented and visionary approach for sustainable use of biodiversity resources. This article concerns “Local Biodiversity Action Plans”, which provide a comprehensive and integrated approach to biodiversity and ecosystem services for the sustainable development of rural municipalities and their local communities. Although biodiversity action planning is not a new concept, bringing a plan to life has significant societal benefits with innovative solutions to help biodiversity conservation while entailing close interaction of science, policy and society. This approach was developed together with project partners and local communities in selected regions of the Western Balkans and it benefits from a range of stakeholders, including social and natural scientists, practitioners, elected representatives of the local communities and end users in the frame of a participatory approach. The conclusion of this article discusses the role of communication and outlines the critical success factors and the challenges ahead for the future.     

Squirrels in suburbia: influence of urbanisation on the occurrence and distribution of a common exotic mammal

Urbanisation is widely considered to promote the establishment of non-native species, but there is limited empirical evidence of the ecological factors driving their responses. The grey squirrel Sciurus carolinensis (Gmelin 1788) is native to North America, but is widespread in the UK and is starting to spread across Europe. It is regarded as one of the world’s worst invasive animals due to its adverse impacts on native biodiversity. We use the non-native grey squirrel population in Sheffield (UK) as a case study to assess which factors limit its distribution and abundance in urban environments. In 2010 the city-wide population of adult squirrels peaked at an estimated 6539 in autumn (0.46 squirrels/ha), with maximum local densities of 8.29/ha. These densities appear to be slightly lower than those recorded in urban environments in the species’ native range. Grey squirrels occurred more frequently at urban sites with larger amounts of green-space in the surrounding region. Local habitat characteristics were, however, more powerful predictors of urban grey squirrel occurrence and abundance than regional availability of green space. Canopy cover, seed bearing trees and supplementary feeders, provided for garden birds, positively influenced grey squirrels. The potential for grey squirrels to connect city dwellers with nature thus appears to be highest in urban locations that have considerable capacity to support native biodiversity. The beneficial impacts of supplementary feeding on grey squirrel populations is notable given concerns that squirrels can adversely influence bird populations. These habitat associations also imply that grey squirrels typically respond negatively to urbanisation, which challenges arguments that urbanisation favours exotic species.