Showing papers on "Urban ecosystem published in 2007"

Green Roofs as Urban Ecosystems: Ecological Structures, Functions, and Services

Abstract: Green roofs (roofs with a vegetated surface and substrate) provide ecosystem services in urban areas, including improved storm-water management, better regulation of building temperatures, reduced urban heat-island effects, and increased urban wildlife habitat. This article reviews the evidence for these benefits and examines the biotic and abiotic components that contribute to overall ecosystem services. We emphasize the potential for improving green-roof function by understanding the interactions between its ecosystem elements, especially the relationships among growing media, soil biota, and vegetation, and the interactions between community structure and ecosystem functioning. Further research into green-roof technology should assess the efficacy of green roofs compared to other technologies with similar ends, and ultimately focus on estimates of aggregate benefits at landscape scales and on more holistic cost-benefit analyses.

The Changing Metabolism of Cities

Abstract: Summary Data from urban metabolism studies from eight metropolitan regions across five continents, conducted in various years since 1965, are assembled in consistent units and compared. Together with studies of water, materials, energy, and nutrient flows from additional cities, the comparison provides insights into the changing metabolism of cities. Most cities studied exhibit increasing per capita metabolism with respect to water, wastewater, energy, and materials, although one city showed increasing efficiency for energy and water over the 1990s. Changes in solid waste streams and air pollutant emissions are mixed. The review also identifies metabolic processes that threaten the sustainability of cities. These include altered ground water levels, exhaustion of local materials, accumulation of toxic materials, summer heat islands, and irregular accumulation of nutrients. Beyond concerns over the sheer magnitudes of resource flows into cities, an understanding of these accumulation or storage processes in the urban metabolism is critical. Growth, which is inherently part of metabolism, causes changes in water stored in urban aquifers, materials in the building stock, heat stored in the urban canopy layer, and potentially useful nutrients in urban waste dumps. Practical reasons exist for understanding urban metabolism. The vitality of cities depends on spatial relationships with surrounding hinterlands and global resource webs. Increasing metabolism implies greater loss of farmland, forests, and species diversity; plus more traffic and more pollution. Urban policy makers should consider to what extent their nearest resources are close to exhaustion and, if necessary, appropriate strategies to slow exploitation. It is apparent from this review that metabolism data have been established for only a few cities worldwide, and interpretation issues exist due to lack of common conventions. Further urban metabolism studies are required.

Spatial heterogeneity in urban ecosystems: reconceptualizing land cover and a framework for classification

Abstract: Urban areas are heterogeneous. Transitions in architecture and building density, vegetation, economic activity, and culture can occur at the scale of city blocks. Ecologists have been criticized for treating the city as homogeneous and urbanization as one-dimensional. To develop ecological understanding of integrated human–natural systems, the fine-scale heterogeneity of their built and natural components must be quantified. There have been calls for the integration of the biophysical and human components of systems, but here we provide a new tool to quantify this integrated heterogeneity by reconceptualizing urban land-use and land-cover classification approaches. This new tool, High Ecological Resolution Classification for Urban Landscapes and Environmental Systems (HERCULES), balances detail and efficiency and is flexible, allowing it to be used for interdisciplinary research, with ancillary datasets, and across urban systems.

Nature and significance of anthropogenic urban soils

Abstract: Anthropogenic and natural urban soils are of increasing significance in a world with accelerating urbanization. Thus, anthropogenic urban soils must be considered as an fundamental ecological asset for land-use planning. Furthermore, they are of interest for fundamental soil sciences, since there properties are rarely investigated and can differ substantially from landscape soils. Numerous studies on their properties exist, in particular with respect to contamination. It is argued that urban soils are ecological assets of cities, a point of view shared with the AKS (working group on urban soils within the German Soil Science Society). In this commentary, an overview of less recognized topics is presented with specific reference to topics such as ‘co-development of anthropogenic urban soils within their cities’ and the principles of ‘stock flow of anthropogenic urban soils forming materials’ are discussed to complete the pedological and ecological view on urban soils. Additionally, the significance of (anthropogenic) urban soils is highlighted to strengthen consideration in urban spatial planning. Historical and recent impacts on soils and parent materials are related with soil properties. Definitions and taxonomic terms for anthropogenic soils are presented. Furthermore, the context with the functionality of such soils is discussed. The principles of mapping and evaluation of anthropogenic urban soils are explained to stress the practicability of management tools for such soils. A semi-quantitative consideration of parent material flows in anthropogenic urban soils indicates the enormous increase of the areas of supply of cities since the pre-industrial period. Since 1950, the inner-urban deposition of solid materials, including dust stopped to increase or increases slowly in the early industrialized regions. In contrast, the deposition and reuse of rubble, inorganic and organic waste as well as dust increases much in the late industrialized regions of the last decades. The significance of anthropogenic urban soils in ecological soil management became obvious by numerous scientific studies. Moreover, it is recognized that management of different areas in urban environments must respect the functionality of their soils. It is therefore of importance that pedology is integrated with related disciplines such as archaeology, history and urban planning. The scientific knowledge, the appropriate methods and tools are now available to promote and support the management of anthropogenic urban soils. It is recommended that research conducted over the past two decades should be introduced into soil management, especially with regard to the evaluation of soil quality. Accordingly, results of collaborative studies by soil scientists and city planners need to be integrated into political frameworks like the European Soil Strategy. It is also recognized that knowledge regarding anthropogenic urban soils in the tropics, the southern hemisphere and far north is lacking, a point which will need to be addressed in the future. This publication is dedicated to the 20th anniversary of the AKS (Arbeitskreis Stadtboden).

Linking ecological and built components of urban mosaics: an open cycle of ecological design

Abstract: Summary 1. By the end of this decade, the majority of people will live in cities and suburban areas. Urban areas, including suburbs and exurbs, are expanding rapidly worldwide. 2. Plant ecology has largely ignored cities, or has primarily focused on the discrete urban green spaces within cities. 3. Plant ecology is increasingly engaging urban ecosystems as integrated natural-human systems, in which human agency is part of the complex of feedbacks. 4. Linking plant ecology with urban design (architecture, landscape architecture, civil engineering and urban planning) can help to integrate research and understanding of plants into the structure of cities, and to make use of urban design projects as ecological research tools. 5. Synthesis . A cycle of ecological design illustrates the linkage of plant ecological research with the ongoing transformation of urban systems by urban designers and civil society. Quality of life, human health, public appreciation of ecological processes in cities, and scientific understanding can all be enhanced by participating in a cycle of ecological urban design.

Urban sprawl metrics: an analysis of global urban expansion using gis

Abstract: We define and present a comprehensive set of metrics for five dynamic attributes of urban spatial structure commonly associated with ‘sprawl’: (a) the extension of the area of cities beyond the walkable range and the emergence of ‘endless’ cities; (b) the persistent decline in urban densities and the increasing consumption of land resources by urban dwellers; (c) ongoing suburbanization and the decreasing share of the population living and working in metropolitan centers; (d) the diminished contiguity of the built-up areas of cities and the increased fragmentation of open space in and around them; and (e) the increased compactness of cities as the areas between their fingerlike extensions are filled in. We also introduce several metrics for key manifestations of sprawl. We present these metrics as well as actual calculations of these metrics for two cities: Bangkok and Minneapolis. A forthcoming paper will present similar results for a global sample of 120 cities.

Habitat structure: A fundamental concept and framework for urban soil ecology

Abstract: Habitat structure is defined as the composition and arrangement of physical matter at a location. Although habitat structure is the physical template underlying ecological patterns and processes, the concept is relatively unappreciated and underdeveloped in ecology. However, it provides a fundamental concept for urban ecology because human activities in urban ecosystems are often targeted toward management of habitat structure. In addition, the concept emphasizes the fine-scale, on-the-ground perspective needed in the study of urban soil ecology. To illustrate this, urban soil ecology research is summarized from the perspective of habitat structure effects. Among the key conclusions emerging from the literature review are: (1) habitat structure provides a unifying theme for multivariate research about urban soil ecology; (2) heterogeneous urban habitat structures influence soil ecological variables in different ways; (3) more research is needed to understand relationships among sociological variables, habitat structure patterns and urban soil ecology. To stimulate urban soil ecology research, a conceptual framework is presented to show the direct and indirect relationships among habitat structure and ecological variables. Because habitat structure serves as a physical link between sociocultural and ecological systems, it can be used as a focus for interdisciplinary and applied research (e.g., pest management) about the multiple, interactive effects of urbanization on the ecology of soils.

Principles and Standards for Measuring Primary Production

Abstract: This volume will lay out the best methods for measuring net primary productivity (NPP) in ecological research. Primary productivity is the rate at which energy is stored in the organic matter of plants per unit area of the earth's surface. NPP is the beginning point of the carbon cycle, so our ability to accurately measure NPP is important. The book includes chapters for each of the critical biome types to offer special techniques that work best in each biome. For example, there are chapters that discuss grassland ecosystems, urban ecosystems, marine pelagic ecosystems, forest ecosystems, and salt marsh ecosystems, among others. All 26 LTER sites will be expected to collect and report data using these methods, but ecologists more generally should also find these methods useful and authoritative. Currently no standard methods or standards exist. Measuring NPP is fundamental to many ecosystem studies at thousands of sites, and having identified standards and methods would be extremely useful for comparing measurements among sites and for compiling a broad scale understanding of the environmental, biological, and nutrition controls on NPP. This book would resemble the Standard Soil Measurement volume in the LTER series in that it reaches well beyond any single LTER site to apply to any ecosystem. It should be rather more widely used than the soil measurements volume, in that measuring productivity is so fundamental to any ecological analyses as well as agronomy, forestry, fisheries, limnology and oceanography.

Effects of Urban Land-Use Change on Biogeochemical Cycles

Abstract: Urban land-use change, the conversion of agricultural recand natural ecosystems to human settlements, has become an important component of global change. Virtually all of the projected increase in the world's population is expected to occur in cities so that by the year 2007 more than half of the global population is expected to live in urban areas (United Nations 2004). Yet, urban settlements and surrounding areas are complex ecological systems that have only recently been studied from a rigorous ecological perspective (Pickett et al. 2001).

Urban and community forestry in the northeast

Abstract: Contributors.- Foreword.- Acknowledgements.- 1. Origins of urban forestry H.D. Gerhold.- 2. Understanding the benefits and costs of urban forest ecosystems D.J. Nowak, J.F. Dwyer.- 3. Arboriculture law in the northeast V.D. Merullo.- 4. Tree ordinances M.V. D'Errico.- 5. Using comprehensive planning to conserve the natural environment W.F. Elmendorf.- 6. Urban and community forestry: planning and design S. Strom.- 7. Tree inventory and systematic management R.S. Wolowicz, M. Gera.- 8. Urban and community forestry financing and budgeting R.L. Tate.- 9. Community involvement in urban forestry programs J. Nichnadowicz.- 10. Soils: the key to successful establishment of urban vegetation G.A. Hawver, N.L. Bassuk.- 11. Selecting trees for community landscapes H.D. Gerhold, W. Porter.- 12. Guide to selecting and specifying nursery stock J. Sellmer, L. Kuhns.- 13. Planting and maintenance J.W. Consolloy.- 14. Pruning D.L. Johnson.- 15. Trees, utilities, and municipalities R.F. Lee, R.S. Wolowicz.- 16. Tree roots vs. sidewalks and sewers W.R. Comery.- 17. Hazard tree inspection, evaluation, and management E.T. Smiley et al.- 18. Integrated pest management D. Smith-Fiola.- 19. Tree appraisal: the goal is equity J.B. Ingram.- 20. Leaf composting P.F. Strom, M.S. Finstein.- 21. Urban tree romovals D.F. Blair.- 22. Recycling urban tree removals E.A. Lempicki, E. Cesa.- 23. Tree city USA J. Rosenow, M. Yager.- 24. A case study of Paramus, New Jersey: a 'tree city USA' community W.R. Comery.- 25. Attracting and managing for wildlife K.E. Clark.- 26. Managing urban ecosystems: A look to the future of urban forestry L.R. Neville.- Index.-

Urban Parks and Sustainable City Planning - The Case of Portimão, Portugal

Abstract: Urban growth creates challenges recognized by the global community. Sustainable development is a widely accepted strategic framework in city planning and urban parks play an important role in it. Nonetheless, it is argued, that urban parks and other open green spaces are important for the quality of life of an increasingly urbanized society. Following the industrial revolution with its massive urbanisation in the 19th century and the explosive growth of urban areas and nature degradation throughout the 20th century, the alienation between people and nature was increased. The urban park movement had objective to increase life quality in the modern city. Sustainability and city regeneration strategies focus mainly on man-made and built components of the urban environment, although, in the last years is noticed an increasing interest for development of nature in cities. In order to exemplify the importance of urban parks for sustainability and the future of the city this paper analyses some emblematic projects that marked the urban park movement in their construction period - the Central Park, the Park Amsterdamse Bos, the Park Andre-Citroen and the City Park of Porto. The role that urban green space play in ecological, social and economic sustainability will be discussed and the case study of the new City Park of Portimao will address the importance of urban green spaces for life quality and sustainable city development.

Cities and Nature

Abstract: Section 1: The Urban Environment in History 1 The City and Nature 2 Environmental Issues in Cities: A Brief History 3 The Industrial City 4 Contemporary Urbanisation and Environmental Dynamics Section 2: Urban Environmental Issues 5 Urban Sites 6 Cities, Environmental Hazards and Disasters 7 Urban Ecology 8 Water Pollution and the City 9 Air Pollution and the City 10 Garbage in the City Section 3: Realigning Urban-Nature Relations 11 Race, Class and Environmental Justice 12 Sustainable Urban Development

Scaling urban environmental challenges : from local to global and back

Abstract: Scaling the Urban Environmental Challenge * Urban Transitions and the Spatial Displacement of Environmental Burdens * Variations of Urban Environmental Transitions: The Experiences of Rapidly Developing Asia-Pacific Cities * In Pursuit of a Healthy Urban Environment in Low- and Middle-income Nations * Improving Urban Water and Sanitation Services: Health, Access and Boundaries * Poverty and the Environmental Health Agenda in a Low-income City: The Case of the Greater Accra Metropolitan Area (GAMA), Ghana * Dynamics of Growth and Process of Degenerated Peripheralization in Delhi: An Analysis of Socio-economic Segmentation and Differentiation in Micro-environments * Motorization in Rapidly Developing Cities * A Comparative Perspective on Urban Transport and Emerging Environmental Problems in Middle-income Cities * Fixing Environmental Agendas in Mexico * In Pursuit of the Sustainable City * The Metabolism of Urban Affluence: Notes from the Greater Manchester City-region * Locating the Local Agenda : Preserving Public Interest in the Evolving Urban World * Index

Density and Outer Urban Development in Melbourne

Abstract: The issue of residential density is again an important issue in strategic land use planning in Australia. For decades, Australian planners generally have accepted the conventional position that increasing the density of urban settlement on the urban fringe will achieve negligible land savings because the amount of land required for non-residential purposes remains constant. This position continues to affect government policy and practice. This article analyses the role of residential density in debates about urban form, and shows the potential for land savings from different scenarios of increased residential density and urban design. The article demonstrates the capacity for increased residential densities in new outer suburbs of cities to significantly contain outward urban growth.

Changes in Urban Density: Its Implications on the Sustainable Development of Australian Cities

Abstract: This exploratory paper seeks to develop a deeper understanding of the phenomenon of urban density and its effects on the sustainability of urban development, functionality and management of Australian cities. The paper explores different attributes of urban density and presents a conceptual framework to explore the relationship of these to sustainability criteria. The work presented in the paper is confined to an exploration of urban density demographic and urban residential development. Other dimensions of density will be explored in future research. The paper presents simple time series measurements of change in urban density for selected Australian cities drawing upon ABS and satellite imagery data. It shows since 1990 the urban areas of Australia’s largest cities (Sydney) are growing at over 2.4% per annum, while the population growth rate is around 1.2%. The population densities of Australian cities have been falling at about 0.8% per annum. If these trends continue, the implications on the sustainability and development of Australian cities could be significant. The paper examines some environmental impacts of urban density on the sustainability of urban systems. It concludes with a brief discussion on the challenges to achieving sustainable urban development in Australian cities.

Beyond the Metropolis: Urban Geography as if Small Cities Mattered

Abstract: Part 1 Preface Part 2 Acknowledgements Part 3 Introduction Chapter 4 Small City Studies and Geographic Perspectives Part 5 Evolution and Growth of Small Cities Chapter 6 From Frontier Outpost to Northern Capital: The Growth and Functional Transformation of Prince George, BC, Canada Chapter 7 Urbanization of the Midwestern Countryside: The Case of Minnesota's Small Cities Chapter 8 Demographic Changes in America's Small Cities, 1990- 2000 Chapter 9 Population Growth, Demographic Changes, and Spatial Distribution of Small Cities in Mexico, 1970- 2000 Part 10 The Internal Structure of Small Cities Chapter 11 Micropolitan Ohio: A Study of Internal Structure of Small Cities Chapter 12 Globalization, Neoliberal Policies, and the Changing Landscapes of Small Cities: The Case Study of Ciudad Lerdo, Durango, Mexico Chapter 13 The Urban Corona Effect and Retail Change in Small Cities: The Case of Central Iowa Chapter 14 Location Dynamics of Economic Activities in America's Small Cities: The Experience of Five Wisconsin Cities Part 15 Planning and Managing Change in Small Cities Chapter 16 Revitalizing Small City Downtowns: The Case of Brandon, Canada Chapter 17 Downtown Retailing and Revitalization of Small Cities: Lessons from Chillicothe and Mount Vernon, Ohio Chapter 18 Managing Downtown Revitalization of Small Cities: Lessons from Kentucky's Main Street Program Chapter 19 Public Transportation in Small Cities: The Case of Marysville and Yuba City, California Chapter 20 Housing and Urban Development Problems in Small Cities: The Case of Ciudad Guzman, Jalisco, Mexico Chapter 21 Public Policy and Development of Small Cities: The Experience of Israel's Development Towns Part 22 Conclusion Chapter 23 The Future of Urban Geography as if Small Cities Mattered Part 24 Index

Handbook on urban sustainability

Abstract: Contributors. Acknowledgements.- Preface: The Ecological Footprint Of Cities And Regions: Comparing Resource Availability with Resource Demand.- Introduction.- Characteristics and Analysis of Urban Sustainable Systems.- Urban Social Sustainability.- The City and Its Environment.- Economy of the City and its Region.- Improving Lives of Slum Dwellers: Challenges and Strategies.- Planning for Sustainable Urban Environments.- Towards Sustainable Municipal Infrastructure Asset Management.- Urban Energy Management.- Urban Transportation Management.- Energy Use and Urban Buildings.- An Example of Creation of Self-Managed Cities.- Urban Wastes Management.- Water in the Urban Environment.- Natural Risk Assessment and Management.- Urban Reconstruction.- Road Map to Urban Sustainability and Decision-Making.- Process for Implementing a Municipal Sustainability Plan.- Glossary. Index.- Colour Plates.

Urban Parks and Sustainable Development - The Case Study of Portimão City, Portugal

Abstract: Following the industrial revolution with its massive urbanisation in the 19th century and the continued explosive growth of urban areas and the decline of nature throughout the 20th century, the alienation between people and the nature was increased. The urban park movement had objective to increase life quality in the modern city. The last years we have seen an increasing interest across Europe in the development of nature in cities. The case study of the City Park of Portimao will be presented and examined with emblematic similar projects that marked the urban park movement in the last decades. The Cental Park of New York, the Amsterdamse Bos, Parc, the Andre-Citroen and the City Park of Porto are discussed with objective to study how the Urban green space contributes to ecological, social and economic sustainability.

Urban Metabolism and Payment for Ecosystem Services: History and Policy Analysis of the New York City Water Supply

Abstract: The interaction of urban cores and their rural hinterlands is considered from an ecological–economic perspective. The concept of ‘urban metabolism’ motivates discussion of urban dependence on geographic regions outside their borders for both sources of inputs and as waste sinks. The U.S. Environmental Protection Agency's 1989 Surface-Water Treatment Rule forces cities to consider the ecosystem services preserved by appropriate land-use management inside suburban and rural watersheds used for urban water supplies. A case study of New York City and its water supply from the Catskill–Delaware watershed system is used to explore these themes. Compensation from the city to watershed communities may be an effective way to motivate protection of those ecosystem functions. Both direct payments and investment in economic development projects consistent with water quality goals are reviewed as policy instruments.

The Spatial Pattern of Land Use in the United States

Abstract: There is currently great interest in understanding and managing the impacts of land-use changes on individual and social well-being. This interest stems from concerns over fiscal, economic, environmental, and social issues related to changes in the spatial pattern of urban land use, including urban decentralization and the conversion of rural land to low-density urban uses. Understanding the forces that affect land-use change requires first getting the facts right. In this chapter, we attempt to describe changes in land-use patterns in the United States over the past several decades and to a lesser extent link them to economic theories designed to explain these changes. In pursuing this course, we draw on papers that have empirically measured land-use patterns or empirically tested economic theories about those patterns. With regard to some issues, the results are robust. But with regard to others, most notably those related to low-density development, considerable uncertainty remains, uncertainty that can be traced to data problems that continue to plague land-use analysis. The chapter begins by presenting data on the major land uses of the USA and changes in those land uses in the recent past, especially conversion of rural to urban land. Some basic facts are examined regarding urban land, including its amount, regional variation, and density, and questions are raised about the ability of current data to measure current land-use phenomena accurately. To illustrate the potential problems, we draw on high-resolution land-use data available for the state of Maryland. We then review what we believe to be major trends in urban land-use changes that have received both theoretical and empirical attention in

Bluespace: a typological matrix for port cities

Abstract: The sea covers more than 70% of the Earth's surface. Now for the first time in history more than half the world's people live in cities and many of the world's most populated conurbations are located on the ocean periphery. Climate change is making littoral zones a potentially productive location for the development of new forms of urban space in coastal cities. Increased urbanisation and the foregrounding of the coastal condition make the association between cities and the sea one of the most important environmental juxtapositions of the 21st century. The aim of this paper is to re-theorise the collision of the public realm and the sea edge, and provide a range of design precedents for this emerging urban space phenomenon. The paper will introduce the concept of ‘bluespace’ and define a matrix with nine instances of how urban space and sea space combine to produce distinct public space types in port cities. Case studies of each type will be presented and discussed in detail with reference to textual and representational descriptions of the space in question.

Quantitative Evaluation of the Uncertainties in the Coordinated Development of Urban Human Settlement Environment and Economy: Taking Changsha City as an Example

Abstract: The human settlement environment problem has become a new focus on urban studies at home and abroad. Sustainable development of urban human settlement is the ultimate target of modern city construction and development. The coordinated development of human settlement and economy is of vital significance to urban sustainable development and urban ecosystem health. It is necessary to review its development and evaluate its coordinating degree. Urban human settlements and economic systems exist in urban ecosystems, which are a structural complexity. Therefore the research is being challenged by some uncertain factors between human settlements and economic systems. More and more attentions have been paid to the researches and the applications of the research result to the human settlement, eco-city and urban sustainable development. However most of the researches were focused on its determinate objective aspects and qualitative analyses while less concern on the quantitative evaluation of coordinated development of urban human settlement environment and economy, especially little on its uncertain aspect. At present, the urgent task is to study the coordinated development of urban settlement and economy in terms of the effect of uncertainty. This paper analyzed the uncertain characteristics, which would be confronted at different stages, such as confirming the index categories, their bound values, and their construction rate, etc. According to the actual urban conditions, many construction principles based on uncertainties were put forward and an indicating system for human settlement and economic evaluation was established. Moreover, the application of fuzzy mathematics presented a new method and a calculation model for the comprehensive assessment of the coordinated development of urban human settlement and economy. The application of the method and model in Changsha city of Hunan Province showed that the assessment results could reflect not only the overall coordinating degree of the city, but also the model of interactive mechanism between urban economic systems and human settlement.