T H E I N T E R R E L A T I O N S H I P OF L A N D S C A P E E C O L O G Y & L A N D S C A P E A R C H I T E C T U R E:

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1 T H E I N T E R R E L A T I O N S H I P OF L A N D S C A P E E C O L O G Y & L A N D S C A P E A R C H I T E C T U R E: A P P L I C A T I O N S F O R T R E N D S I N U R B A N I Z A T I O N Prepared by M. Viola for NRS 534, May 2011 I N T R O D U C T I O N Landscape ecology, as the name implies, is the study of the composition, structure, and function of landscapes, among which a common theme is their patterns, processes, and changes (Hobbs 1997). In recent years, landscape ecology as a science has progressed towards studying and improving relationships between urban development and ecological processes in the environment and particular ecosystems. This is largely due to trends in urbanization, which has seen the global human population shift from predominantly agrarian to urban throughout the past century (Wu 2008). As a result, integration between landscape ecology and landscape architecture, in both theory and practice, is imperative. Landscape architecture encompasses the analysis, planning, design, management, and stewardship of the natural and built environments (Chen and Wu 2009), and involves the systematic investigation of existing social, ecological, and geological conditions and processes in the landscape, and the design of interventions that will produce the desired outcome. The scope of the profession includes urban design, environmental restoration, historic preservation, and site, urban, and regional planning. This paper will discuss driving forces of landscape change, the future of landscapes as they relate to landscape ecology, effects of urban pattern on ecosystem function, ecological methods of analyzing the urban landscape, and landscape ecology as a foundation for landscape architecture and approach to urban sustainability. L A N D S C A P E C H A N G E Driving forces of are the forces that cause observed landscape changes, and are influential processes in the evolutionary trajectory of the landscape (Bürgi and Hersperger 2004). Five major types can be identified, including socioeconomic, political, technological, natural and cultural. New directions in assessing landscape change have utilized comparative studies across administrative borders and along transects. As landscapes change, humans, flora, and fauna adapt, with more time allowed in the process equating to smoother change and higher likelihood to cope. These new approaches aim to improve the ability of studying these processes, in addition to spatial patterns, which are generally excellent precursors of landscape change (Bürgi and Hersperger 2004). The implications of studying driving forces of landscape change directly relate to global urbanization and the need for interdisciplinary and integrative work in planning and management applications. F U T U R E L A N D S C A P E S Landscape ecology is also prepared to play a major role in current conservation and land use issues, particularly in responding to problems arising from human-induced global change (Hobbs 1997). As these issues are present at the landscape scale, a planning approach is relevant for land use considerations and decision-making. However, a major shift in emphasis and thinking is required in order to plan for future landscapes that are ecologically sustainable. In support of this, Hobbs (1997) suggests the following: 1) The future is not somewhere we are going, it is something we are making; 2) We can follow the path to the future, or help in its construction; 3) It helps if we know where we want to go; 4) Building paths to the future is easier if we all work together, and 5) It is much better to build paths that will actually be used.

2 U R B A N P A T T E R N & E C O S Y S T E M F U N C T I O N From an ecological perspective, as we progress towards a more urban landscape, patch structure is affected through the alteration of size, shape, interconnectivity, and composition of natural patches (Alberti 2005). New urban structures alter the mosaic of patches, which are heavily influenced by land use, and subsequently affect ecosystem function, which is the ability of earth s processes to sustain life over long periods of time. Since ecological processes are closely interrelated with the landscape, mosaics resulting from urbanization have implications on ecosystem dynamics, including net primary productivity, biodiversity, material and nutrient cycles, and disturbance regimes. Explicitly linking urban patterns to ecosystem function is critical (Alberti 2005), and the development of strategies for urban planners and managers is essential for minimizing the impacts of urban growth. E C O A N A L Y S I S Traditional site analysis is a critical component of the planning process, as it reveals opportunities and constraints that guide design efforts. Landscape ecology is similar, in that it provides numerous alternative methods for analyzing the urban landscape. One method that is particularly relevant is landscape structure indices for assessing urban ecological networks (Cook 2002). In this method, Cook demonstrates how landscape structure can be used to assess the viability of urban ecological networks, which are increasingly being considered as a suitable approach to improving the ecological value of urban open space systems. The objective of his analysis is to measure the difference between alternative ecological network scenarios using landscape structure indicators. He utilizes three analyses; patch content, corridor content, and network structure, in order to describe differences between scenarios. The results of Cook s analysis indicate that notable improvement in ecological value can be achieved through implementing planning strategies for open space systems while embracing the concept of ecological networks. T H E R O L E O F L A N D S C A P E E C O L O G Y Final thoughts will cover landscape ecology as both a foundation for landscape architecture and an effective approach to urban sustainability. It has already been established that landscape ecology contributes to methods of landscape assessment, evaluation, and systems thinking in landscape planning, but its potential contribution towards a holistic design approach in landscape architecture is limited, largely due to traditional landscape design methodology that is static, fragmentary, and compartmentalized, and thus ill suited to dynamic living systems (Makhzoumi 2000). Contrastingly, the holistic approach of landscape ecology maintains the potential for an alternative design method: ecological landscape design, which integrates ideals from both landscape ecology and landscape architecture. Ecological landscape design is based on a holistic understanding of the landscape, which encourages a dynamic and responsive approach, and is guided by three fundamental, mutually exclusive objectives: the maintenance of landscape integrity, promoting landscape sustainability, and reinforcing the natural and cultural spirit of place (Makhzoumi 2000). Landscape ecology can also significantly contribute to and gain from sustainability science, a rapidly emerging transdiscplinary field that provides the scientific basis for sustainable development (Wu 2008). A landscape ecological perspective is essential for urban sustainability research and practice, which has much to do with landscape and urban planning and design. Urban sustainability also needs a spatially explicit, multi-scaled, and crossdisciplinary framework, which landscape ecology provides (Wu 2008). Urban sustainability is intrinsically related to landscape sustainability, thus the development of sustainable cities must consider the larger landscape and global context indicated by its ecological footprint. As such,

3 our challenge is not to stop urbanization, but rather speed up the process of designing and planning better cities (Wu 2008). C O N C L U S I O N S In conclusion, as global human population trends shift towards urbanization, the integration between landscape ecology and landscape architecture in both theory and practice is imperative. Understanding the driving forces of landscape change, realizing the effects of urban pattern on ecosystem function, utilizing ecological methods for urban landscape analysis, and integrating landscape ecology into landscape architecture and urban sustainability will collectively result in an easier transition towards a more ecological future. As a final thought, the word sustainability has become overused, especially recently in design and planning, that its meaning has diminished. Although its philosophical scope has grown, everyone has his or her own definition, which detracts from the common goal. Rolling many important issues into one imprecise word dilutes their importance. As such, it is vital to return to basics, speak about issues succinctly, and stop using buzzwords in a general way.

4 A N N O T A T E D B I B L I O G R A P H Y Alberti, M The Effects of Urban Patterns on Ecosystem Function. International Regional Science Review, 28: Alberti discusses how cities are growing rapidly worldwide, and as a result, our ecosystems are becoming increasingly dependent on patterns of urban growth. She explains how landscapes differ in patch dynamics and urban patterns have different effects on ecosystem function, including productivity, biodiversity, nutrient cycling, and disturbance regimes. Of particular interest is Alberti s study in Puget Sound, which used landscape metrics to measure urban landscape patterns and assess relationships between urban development and ecological conditions. She also considers implications for future studies, suggesting that linking urban patterns to ecosystem function is critical to advance urban ecological research, while subsequently developing strategies for urban planners and managers to minimize impacts of urban growth. Bürgi, M., A.M. Hersperger, and N. Schneeberger Driving forces of landscape change current and new directions. Landscape Ecology, 19: Bürgi and Schneeberger introduce landscape as areas where the effects between society and nature become visible, explaining that because society and nature are dynamic, landscape change is inherent. They define driving forces as those causing observed landscape changes and introduce new directions for studying landscape change relative to driving forces, including comparative studies across administrative borders and along transects. The authors discussion on putting these new directions into perspective is particularly interesting, as it establishes motivation to find general patterns of landscape change as a precursor (to landscape change). Their promotion of a new, standard procedural approach to study the driving forces of landscape change, which utilizes a three-step framework of system definition, analysis, and synthesis, is also interesting, as it calls for interdisciplinary and integrative work in planning and management applications. Chen, X. and J. Wu Sustainable landscape architecture: implications of the Chinese philosophy of unity of man with nature and beyond. Landscape Ecology, 24: Chen and Wu describe how as humans increasingly dominate the world, its ecosystems and landscapes are becoming more domesticated, resulting in global environmental problems. With the expectation of major population increase to occur in cities, they call for integration between landscape ecology and landscape architecture in order to properly design, plan, and manage urban landscapes in a sustainable manner, while advocating traditional Chinese principles and models. The authors propose a conceptual framework for sustainable landscape architecture that is built on the philosophy of unifying man with nature. This framework considers three interesting functions for designing sustainable landscapes, including the production of goods and services that generate economic benefit, the provision of life enrichment services, including creating spaces, facilities, and opportunities for recreation, healthy living, and social functions, and ecological conservation to maintain a balance of biodiversity and ecosystem functioning.

5 Cook, E.A Landscape structure indices for assessing urban ecological networks. Landscape and Urban Planning, 58: Cook explains how landscape structure can be used to assess the viability of urban ecological networks, which are increasingly being considered as a suitable approach to improving the ecological value of urban open space systems. He assesses how ecological network viability can be undertaken through patch and corridor content and network structure analyses. Cook s triumph is in his analysis of and subsequent plan for the Phoenix metropolitan area, which employs a series of management, preservation, and restoration strategies to improve the ecological value. His optimal patch, corridor, and network adjustments demonstrate that notable improvement in ecological value can be achieved through the implementation of planning strategies that strive for ecological integrity. Flores, A., et al Adopting a modern ecological view of the metropolitan landscape: the case of a greenspace system for the New York City region. Landscape and Urban Planning, 39: This study reviews how the transformation towards urban landscape has social and ecological consequences for both urban and rural residents, citing concern about environmental quality and long-term livability of urban areas as a major focus amongst planning professionals. It suggests that incorporation of ecological knowledge is a paramount strategy for protecting and restoring critical environmental resources. Ultimately, the authors present a framework for incorporating ecological thinking into a regional plan of the New York City Metropolitan Area through five key ecological principles content, context, dynamics, heterogeneity, and hierarchies. An interesting method utilized by the authors is the application of these principles in the development of objectives based on the Greensward campaign, including creating regional reserves, invigorating existing greenspaces in highly urbanized environments, and creating a regional network of greenspaces. Furthermore, they offer specific recommendations for effectively incorporating their framework in future planning efforts and highlight key strengths and weaknesses. Hobbs, R Future landscapes and the future of landscape ecology. Landscape and Urban Planning, 37:1-9. Hobbs discusses how the field of landscape ecology is poised to play a major role in tackling major conservation and land use issues, as well as developing responses to problems arising from human-induced global change. He reports on the status of landscape ecology as a science, both in traditional and integrative manners, helps to understand landscape structure, function, and change, and introduces practical applications of landscape ecology. His points regarding the future of landscape ecology are both interesting and pertinent, suggesting that (at the time this article was written) landscape ecology had surprisingly little to offer those wishing to plan and manage the landscapes of the future. However, his proposed shifts in emphasis and thinking are perhaps even more relevant today, articulating that our actions dictate the future, humanity is responsible for the outcome, and that not only must we plan for the future together, but we must follow through. Li, F., et al Comprehensive concept planning of urban greening based on ecological principles: a case study in Beijing, China. Landscape and Urban Planning, 72:

6 This article demonstrates how the world is quickly becoming an increasingly urban place, with some 65% of the world s population expected to be urban by the year As a result, natural ecosystems are replaced by urban development, which distances people from natural spaces. In order to counter these trends, the authors outline the development of a conceptual ecological framework and illustrate how the institution of urban greening may help achieve long-term sustainability in Beijing City. Interesting aspects of their ecological concept plan include the consideration of multiple spatial (neighborhood, city, and regional) and temporal (until 2008, until 2020, and long-term) scales, as well as the idea of vertical greening for highdensity settlement, which encompasses roof gardens and wall, balcony, and windowsill greening as an effective way for increasing greenspace amongst high-rise building areas. Luck, M. and J. Wu A gradient analysis of urban landscape pattern: a case study from the Phoenix metropolitan region, Arizona, USA. Landscape Ecology, 17: Luck and Wu describe how urbanization transforms natural landscapes worldwide, resulting in various effects on structure, function, and dynamics of ecological systems. As such, they stress the importance for natural resource managers, land use planners, and conservationists to consider these transformations and their subsequent ecological consequences. The authors suggest the use of gradient analysis integrated with landscape pattern metrics to quantitatively characterize urbanization patterns of metropolitan areas. The authors results are interesting, concluding through a combination of landscape metrics and gradient analysis, that in general, land use types change with distance away from urban centers, different land use types have their own unique spatial signatures, urbanization gradients can be detected using landscape pattern analysis, and urban gradients differ among landscape metrics. Makhzoumi, J.M Landscape ecology as a foundation for landscape architecture: application in Malta. Landscape and Urban Planning, 50: Makhzoumi reports that since its inception, ecology has increasingly provided scientific foundation for understanding environmental processes, managing natural resources, and developing sustainably. She explains how landscape ecology has successfully contributed to methods of landscape assessment and evaluation, as well as landscape planning. However, in landscape architecture, its potential contribution is limited, largely due to traditional design methodology that does not reflect the dynamic attributes of living systems. Makhzoumi argues for ecological landscape design as an alternative methodological approach, and applies its ideals in a master plan for a site in the semi-arid Mediterranean region of Malta. She discusses three interesting advantages of an ecological landscape design approach: moving the designer away from a viewpoint of landscape that is dominated by visual attributes towards a more dynamic and comprehensive perception, encouraging design solutions that develop from an understanding and appreciation of the historical idiosyncrasies of a specific site or region, and implying a school of design that is aware of the natural, historical, social, and cultural factors that have shaped a regional landscape and aims to create future environments that are appropriate. Musacchio, L.R The scientific basis for the design of landscape sustainability: A conceptual framework for translational landscape research and practice of designed landscapes and the six Es of landscape sustainability. Landscape Ecology, 24:

7 Musacchio explains that in recent decades, landscape researchers and practitioners have focused increasingly on human-dominated environments and their place-based problems, including the effects and impacts of urbanization. Through sustainability science, they are evaluating how values, behaviors, and actions of individuals and communities influence the structure, function, and change of designed landscapes in an urbanizing world. As a result, she introduces a conceptual framework for designed landscapes and urbanization that synthesizes emerging trends in order to advance research and practice. Of particular interest are six key characteristics and principles presented by Musacchio, which formulate the core of the conceptual framework and relate knowledge to sustainability science and landscape research and practice. Pickett, S.T.A., and M.L. Cadenasso Linking ecological and built components of urban mosaics: an open cycle of ecological design. Journal of Ecology, 96:8-12. Pickett and Cadenasso report that more than half of the world population will live in urban areas by 2010, and question how the science of plant ecology will address this global trend. They continue with highlighting the role of plant ecology in the expanding urban ecosystem, and explore the intersection of plant ecology and urban design in order to improve ecological understanding and quality of life in urbanized areas. Their open cycle of ecological urban design is particularly interesting, as it explores potential social and scientific benefits of linking ecology with urban design. Furthermore, as an example, they apply their framework to Baltimore, Maryland, and propose examining the vegetative structure of the urban landscape, identifying management practices, interacting with communities in need of new designs, and ultimately implementing these designs in their appropriate locations. Wu, J Making the Case for Landscape Ecology: An effective Approach to Urban Sustainability. Landscape Journal, 27: Wu demonstrates a historic turning point in human civilization, as we are transforming from a predominantly agrarian to mostly urban species. He suggests that given the various environmental problems associated with cities, ecology has much to offer in urban sustainability, addresses different perspectives in urban ecology, and proposes a transdiscplinary framework for studying and developing sustainable landscapes. Wu s landscape ecology approach to urban sustainability is interesting, suggesting that landscape ecology is essential in sustainability research and practice for several reasons, the first of which is that the human landscape represents the most appropriate scale for studying and maintaining sustainability because nature-society interactions can be addressed. He continues to explain that landscape ecology: provides a basis for dealing with issues at multiple scales, has developed numerous interdisciplinary approaches, offers theories and methods for studying relationships, provides a useful suite of methods and metrics, and provides theoretical and methodological tools.