If we are to create a sustainable world – one in which we are accountable to the needs of all future generations and all living creatures – we must recognize that our present forms of agriculture, architecture, engineering, and technology are deeply flawed. To create a sustainable world, we must transform these practices. We must infuse the design of products, buildings and landscapes with a rich and detailed understanding of ecology.(1)
Landscape architect, Ian McHarg discusses survival on earth and how we should plan and design for “better fitting” environments. To illustrate his point he relates the story of an astronaut in his capsule. “An aquarium lines the walls of the capsule, containing algae and decomposers. It is a closed system and works like this. Sunlight falls upon the algae, which use carbon dioxide, water, air, and light to fix carbon, and then expel oxygen. The astronaut breathes air, consumes oxygen, and exhales carbon dioxide, which the algae absorb. Thus, there is a closed cycle of oxygen and carbon dioxide. The astronaut drinks, then pees into the aquarium; water condenses on the outside and is collected by the astronaut – a closed cycle of water. The astronaut hungers, he collects some algae and eats. In due time he defecates into the medium where live the decomposers that reduce the waste into nutrients employed by algae, which grow, and which the astronaut eats. Here is a closed cycle of food. There is one input-light; one export – heat. Oxygen, carbon dioxide, water, food, wastes, and nutrients go ‘round and ‘round”.(2)
This is a simple model, but all the essentials are there for a perfect fit. This is the way nature works; each part has its place and contributes to the health of the whole. “Surely it is better to understand the natural processes, and act accordingly”, McHarg contends, “than to subjugate nature”.(3)
He argues for a search for fit environments and refers to Lawrence J. Henderson’s assertion that there is a necessity for all organisms to find the fittest available environment, adapt it and the self to accomplish better fitting. If we assume that sustainability incorporates the survival of the human race, we can be confident that both present and future generations will need the vital life support functions of a healthy environment. These functions are called ‘critical natural capital’, and they cannot be substituted by human capital. So if we are to achieve a better fit, we must first be sure that the resource consumption and waste generation associated with patterns of urban development do not threaten critical natural capital because current patterns are clearly not sustainable.(4) Ecological design is a way to understand how to achieve ‘a better fit’.
According to Van der Ryn and Cowan(5), ecological design embraces conservation, regeneration and stewardship alike. Ecological design occurs in the context of specific places. It grows out of place and responds to the particularities of place: the soils, vegetation, climate, topography and the availability of water. It seeks locally adapted solutions that can replace matter, energy, and waste with design intelligence. Such an approach matches biological diversity and cultural diversity rather than compromising both the way conventional design solutions do. Ecological design brings the natural flows to the foreground. It celebrates the flow of water on the landscape, the fertility of the earth and the beauty of vegetation. It renders the invisible visible. Ultimately, ecological design deepens our sense of place. Ecological design is a way of integrating human purpose with nature’s own flows, cycles and patterns. It begins with the richest possible understanding of the ecological context of a given design problem and develops solutions that are consistent with the cultural context. Ecological designers are facilitators and catalysts in the cultural processes underlying sustainability and take a systems approach to design. Systems design is an exceptionally trans-disciplinary process and landscape architecture is one of the disciplines that have a key role to play in the design of our built environment.
When asked where landscape architects work, “many people might point out their back door to the garden. It would be more accurate, however, to look out the front door. The landscape is anywhere and everywhere outdoors, and landscape architects are shaping the face of the Earth across cities, towns, and countryside alike. Landscape architecture involves shaping and managing the physical world and the natural systems that we inhabit. Landscape architects do design gardens, but what is critical is that the garden, or any other space, is seen in context. All living things are interdependent and the landscape is where they all come together. Context is social, cultural, environmental and historical, amongst other considerations. Landscape architects are constantly zooming in and out from the details to the big picture to ensure that balance is maintained.”(6)
Landscape architecture operates at the interface of art and science. The art provides a vision for a landscape and the science includes an understanding of the social and natural systems, including geology, soils, plants, topography, hydrology, climate and ecology. “The [landscape architects] challenge is to awaken the rich potential that resides within this overlap of disciplines through a re-invigoration of the connection between beauty and the environment … such that our landscapes can be beautiful and sustainable”.(7)
Because landscape architects design the setting for the built environment it’s not unsurprising then, that a new consciousness has crept into the design of landscapes – an awareness of the fragile environment and sensitivity to the natural environment and its ecological limits. No longer can landscapes be made in a void, but rather they must relate and respond to their surroundings. Sustainable landscape design therefore requires holistic, ecologically based strategies to create landscapes that do not alter or impair but instead help repair and restore existing site conditions. Site systems such as plant communities, soils, and hydrology must be respected as patterns and processes of the living world. These strategies apply to all landscapes, no matter how small or how urban.
This new consciousness suggests an approach that is somewhat different from conventional design. Birkland suggests that “what is required is a move from traditional ‘remedial’ approaches to preventative ‘systems design’ solutions that restore the ecology, foster human health and prioritise universal well-being over private wealth accumulation. Designers in all fields and walks of life have a crucial role to play in this transformation. It is now possible to design products, buildings, and landscapes that purify the air and water, generate electricity, treat sewage and produce food. Instead of applying generalised analyses, goals, criteria, techniques and indicators to any situation (as did ‘modernism’ in architecture) the design of appropriate case-specific, problem solving tools should form a fundamental part of the design process.” (8)
Useful in understanding sustainable ecologically-based landscape design are the “Valdez Principles for Site Design,” developed by Andropogon Associates.(9) These strategies are especially important to correctly integrate the built environment into its setting (the landscape).
- Recognition of Context. No site can be understood and evaluated without looking outward to the site context. Before planning and designing a project, fundamental questions must be asked in light of its impact on the larger community.
- Treatment of Landscapes as Interdependent and Interconnected. Conventional development often increases fragmentation of the landscape. The small remaining islands of natural landscape are typically surrounded by a fabric of development that diminishes their ability to support a variety of plant communities and habitats. This situation must be reversed. Larger whole systems must be created by reconnecting fragmented landscapes and establishing contiguous networks with other natural systems both within a site and beyond its boundaries.
- Integration of the Native Landscape with Development. Even the most developed landscapes, where every trace of nature seems to have been obliterated, are not self-contained. These areas should be redesigned to support some component of the natural landscape to provide critical connections to adjacent habitats.
- Promotion of Biodiversity. The environment is experiencing extinction of both plant and animal species. Sustaining even a fraction of the diversity known today will be very difficult. Development itself affords a tremendous opportunity to emphasize the establishment of biodiversity on a site. Site design must be directed to protect local plant and animal communities, and new landscape plantings must deliberately re-establish diverse natural habitats in organic patterns that reflect the processes of the site.
- Reuse of Already Disturbed Areas. Despite the declining availability of relatively unspoiled land and the wasteful way sites are conventionally developed, existing built areas are being abandoned and new development located on remaining rural and natural areas. This cycle must be reversed. Previously disturbed areas must be re-inhabited and restored, especially urban landscapes.
- Making a Habit of Restoration. Where the landscape fabric is damaged, it must be repaired and/or restored. As most of the ecosystems are increasingly disturbed, every development project should have a restoration component. When site disturbance is uncontrolled, ecological deterioration accelerates, and natural systems diminish in diversity and complexity. Effective restoration requires recognition of the interdependence of all site factors and must include repair of all site systems – soil, water, vegetation, and wildlife.
The above strategies serve as guidelines in landscape design and challenge the design for appropriate development. Emerging from these strategies are site-adaptive considerations, which are critical to achieving sustainable landscape design.(10)
The greatest challenge in achieving sustainable landscape design is to realize that much can be learned from nature. When nature is incorporated into designs, spaces can be more comfortable, interesting, efficient and beautiful. It is important to understand natural systems and the way they interrelate in order to work within these constraints with the least amount of environmental impact. Like nature, design should not be static but always evolving and adapting to interact more intimately with its surroundings.
- Wind – The major advantage of wind in landscape development is its cooling aspect. For example, trade winds in our sub-tropical environments often come from the northeast to the southeast quadrant, orientation of structures, and outdoor gathering places to take advantage of this cooling wind movement, or “natural” air conditioning. Native cultures understand this technique quite well, and local structures reflect these principles. Of course the other consideration is to ensure that structures or outdoor gathering spaces are protected from cold and / or strong prevailing winds.
- Sun – Where sun is abundant, it is imperative to provide shade for human comfort and safety in activity areas (e.g. pathways, patios). The most economical and practical way is to use natural vegetation, slope aspects, or introduced shade structures.
- Rainfall – Many settings must import water, which substantially increases energy use and operating costs, and makes conservation of water important. Rainfall should be captured for a variety of uses (e.g., drinking, bathing, irrigation) and this water reused for secondary purposes (e.g., flushing toilets, washing clothes). Stormwater or excess runoff from developed areas should be channelled and discharged in ways that allow for groundwater recharge instead of soil erosion. Minimizing disturbance to soils and vegetation and keeping development away from natural drainage ways protects the environment as well as structures within it.
- Topography – Slopes do not have to be an insurmountable site constraint if innovative design solutions and sound construction techniques are applied. Topography can potentially provide vertical separation and more privacy for individual structures. Changes in topography can also enhance and vary the way a visitor experiences the site by changing intimacy or familiarity. Again, protection of soil and vegetation are critical concerns in high slope areas, and elevated walkways and point footings for structures are appropriate design solutions to this problem.
- Geology and Soils – Designing with geologic features such as rock outcrops can enhance the sense of place. For example, integrating rocks into the design of a deck or boardwalk brings the visitor in direct contact with the resource and the uniqueness of a place. Soil disturbances should be kept to a minimum to avoid erosion of fragile t soils and discourage growth of exotic plants. If limited soil disturbance must take place, a continuous cover over disturbed soils with erosion control netting should always be maintained.
- Aquatic Ecosystems – Development near aquatic areas must be based on an extensive understanding of sensitive resources and processes. In most cases, development should be set back from the aquatic zone and protective measures taken to address indirect environmental impacts. Particularly sensitive habitats such as beaches should be identified and protected from any disturbance.
- Vegetation – Exotic plant materials, while possibly interesting and beautiful, are not amenable to maintaining healthy indigenous ecosystems. Sensitive indigenous plant species need to be identified and protected. Existing vegetation should be maintained to encourage biodiversity and to protect the nutrients held in the biomass of indigenous vegetation. Indigenous planting should be incorporated into all new developments. Vegetation can enhance privacy, be used to create “natural rooms,” and be a primary source of shade. Plants also contribute to the visual integrity or natural fit of a new development in a natural setting. In some cases, plants can provide opportunities for food production and other useful products on a sustainable basis.
- Wildlife – Sensitive habitat areas should always be avoided. Encouraging wildlife to remain in the area. This can be achieved by maintaining as much original habitat as possible.
- Visual Character – Natural vistas should be used in design whenever possible. Open up the design to take advantage of beautify vistas and to screen visual intrusions.
Local archaeology, history, and people are the existing matrix into which designed public landscapes must fit. Sustainable principles seek balance between existing cultural patterns with new development. Developing an understanding of local culture and seeking their input in the development processes can make the difference between acceptance and failure.
- Archaeology – A complete archaeological survey prior to development is imperative to preserving resources. Once resources are located, they can be incorporated into designs as an educational or interpretive tool. If discovered during construction activities, work should be stopped and the site re-evaluated. Sacred sites must be respected and protected.
- History – Cultural history should be reinforced through design by investigating and then interpreting vernacular design vocabulary. Where appropriate local design elements and architectural character should be analysed and employed to establish an architectural theme for new development.
- Indigenous Living Cultures – Cultural traditions should be encouraged and nurtured. A forum should be provided for local foods, music, art and crafts, lifestyles, dress, and architecture, as well as a means to supplement local incomes (if acceptable). Traditional harvesting of resource products should be permitted to reinforce the value of maintaining the resource.
Increased ecological knowledge is at the core of sustainable landscape design. When taking an ecological approach to landscape design, components defer to the character of the landscape they occupy so that the experience of the landscape will be paramount and restoration of the land can take place. Instead of only human functional needs driving the design, site components respond to the spatial character, climate, topography, soils, and vegetation as well as the existing cultural context, to achieve “places that are less intrusive yet more rewarding, less fashionable yet more enduring”(11) … and they are beautiful and sustainable!
However, a word of caution is needed when we consider the notion of ‘sustainability’. The word has been on just about everyone’s lips – including corporate lips – and this should signal a warning. The concept has “achieved a degree of meaninglessness, with LEED certification [or any of the new rating systems] today anointed as the only worthy design criterion. I am troubled”, Treib continues, “by any design addressed to a single goal or parameter (including purely aesthetic acts removed from functional or social purpose). Might not a better approach be to adopt the adverb ‘sustainably’ to describe how we should design, rather than posing the noun ‘sustainability’ as a single goal? Or, to put it a different way, to use an ecological consciousness to guide the way we design for a greater purpose? “(12)
Sadly, we often stop at the level of indigenous planting, green roof or wetland design, rather than considering these ‘living systems’ as a means for achieving an aesthetic level beyond the merely functional or ‘sustainable’. “The photographer Edward Weston once wrote that one should photograph a thing ‘not for what it is, but for what else it is’. Achieving that ‘what else’ is what makes landscape design an art. Without such aspirations, we operate only at the level of environmental plumbing. Plumbers are needed of course, but so too are artists. Rather than considering the situation as an either/or, I prefer to think of it as a both/and, with the ultimate goal being to elevate pragmatics to the level of poetics.”(13)
On 10 September 1990, Ian McHarg received the National Medal of Art from President Bush. Included in Bush’s remarks was, according to McHarg “an astonishing and totally unexpected statement: ‘Let us hope that in the next century the finest accomplishment of art will be the restoration of the land.’ The ecological view and the skills of landscape architecture and ecological planning must contribute leadership for this restoration – it is, indeed, a quest for life.”(14)
This article was first published in The Green Building Handbook, Volume 4, 2012.
Article by Graham A. Young PrLArch
Senior Lecturer, Department of Architecture, University of Pretoria
Principal, Newtown Landscape Architects cc
- Van der Ryn, S. and Cowan, 1996. S. Ecological Design. Island Press, Washington, D.C
- McHarg, I. 1996. A Quest for Life, John Wiley and Sons Inc., New York. pp 242
- McHarg, I. 1996. A Quest for Life, John Wiley and Sons Inc., New York. pp 248
- Owens, S: ‘Can land use planning produce the ecological city?’ Town and Country Planning, 1994, Vol. 63 No. 6, pp170-173
- Van der Ryn, S. and Cowan, 1996. S. Ecological Design. Island Press, Washington, D.C
- Waterman, T. 2009. The Fudementals of Landscape Architecture. AVA Publishing, Lausanne, Switzerland. pp 8
- Kate Cullity in: Richardson, T. 2011. Futurescapes. Thames and Hudson, London. pp11
- Birkeland, J. 2002. Design for Sustainability. Earthscan Publications Ltd. London. pp 1 – 2
- United States Department of the Interior, 1993. Guiding Principles of Sustainable Design, U.S. Government Printing Office. pp 41
- United States Department of the Interior, 1993. Guiding Principles of Sustainable Design, U.S. Government Printing Office. pp 48 – 50
- Marc Treib in: Richardson, T. 2011. Futurescapes. 1ST ed. Thames & Hudson, London. pp15
- Marc Treib in: Richardson, T. 2011. Futurescapes. 1ST ed. Thames & Hudson, London. pp13
- Marc Treib in: Richardson, T. 2011. Futurescapes. 1ST ed. Thames & Hudson, London. pp14
- McHarg, I. 1996. A Quest for Life, John Wiley and Sons Inc., New York. pp 375