The Ecosystems Approach to
Urban Environmental Management
Operationalizing the Cities as Sustainable Ecosystems (CASE) Initiative
Environment as the Common Denominator
'Environment' means different things to different people. For some, it means separating the
garbage into burnable and non-burnable items. To others it means saving on electricity or
using less water. The term 'environment' may be associated with restoring the vitality of
tropical rain forests, maintaining biodiversity and arresting desertification. Developing
healthy, sustainable and safe communities becomes important to yet others. The environment
also means agricultural and industrial production that is sound and 'green'. Some associate
man-made chemical and nuclear hazards with concrete environmental policies. All of these
views are right in their own way, and are united in its concern for the cyclical effects that the
environment has on the day-to-day lives of current and future generations, and vice versa.
The concern and problems associated with the environment have placed such issues high on
the agenda of many bilateral and multilateral meetings. The Earth Summit of 1992 in Rio de
Janeiro managed to highlight and channel efforts in understanding and acting on
environmental problems, making it a key issue to be tackled in trade and commerce, in
economic and social development, and in science and technology. Subsequent summits and
congresses the Social Summit and the Beijing Conference on Women in 1995, the City
Summit/Habitat II in 1996, not to mention innumerable regional, national and local meetings
all had the larger global environment as a key common denominator in its action plans.
It is only in the last two decades that a better understanding of the effects of changing
environments and ecosystems has been developed. Interconnectedness of these factors has
forced particular attention on human lifestyles and living conditions that has a profound effect
on its surroundings. Most, if not all, environmental problems that we currently face can be
directly or indirectly traced back to the legacy of lifestyles that we are inheriting and leading
as human beings. Nowhere is this more true that in concentrations of gregarious urban
lifestyles that are becoming the option of choice for the majority of humanity.
The Master Culprit: Urban Environments
Urban lifestyles and consumption patterns have far-reaching and long-term effects not only on
its immediate boundaries, but also on the entire region in which it is positioned. Cities and
towns in most countries around the world have been gaining considerable attention due to the
large number of households migrating to cities and its consequent effects. It has also been due
to the centrality of goods and services that cities offer, emerging over the last few decades as
the major form of settlement. By the turn of this century, we will be witness to a ubiquitous
scenario where more people will live in and around cities than in rural areas. In 1800, only 50
million people lived in towns and cities worldwide. During 1975, there were 1.5 billion, and
by the year 2000, this will be three billion - more than the entire population of the world in
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1960. Proximity to decision-makers and financial markets, large pools of skilled and unskilled
workers, and other advantages have made such urban areas the engines of growth for the
countries and regions where they are situated. For example, despite the environmental and
social problems that it is facing, Bangkok's contribution to the national GDP has been
estimated to be more than the combined output of all other cities in Thailand.
The result of this has been the explosive growth of urban areas, bringing with it a host of
negative effects. Population concentration in increasingly smaller land masses has caused a
drastic decline in the quality of living both in the residential and work fronts. Cities have, in
effect, become a barometer of humankind's progress into the 21st century, whether this is an
upward or downward trend. Such a scenario has had ripple effects on a variety of sectors such
as education, health, labour/job markets, and economic activities.
The growth and effect of an urban area should be seen not only in terms of its immediate
boundaries, but also in terms of the resources necessary to sustain its population. An
illustrative example is that of the Greater London area. The land mass that generates the
resources necessary to sustain the population of London, called the 'urban footprint,' is
actually slightly less than the entire land area of UK! This illustrates the complex
interrelationship and interdependence of urban areas and their surrounding hinterland.
Similarly, according to the Earth Council's report, "Ecological Footprints of Nations"
Japanese lifestyles generate a demand for 6.25 hectare per capita (for resources such as energy,
arable land, pasture, forest, built-up area, etc.). But the supply has been only 1.88 hectare per
capita. This leaves a 'ecological deficit' of 4.37 hectare per person that has to be met from
outside the country. The conurban region of Tokyo had a 1995 population of 26.8 million. For
Tokyo alone, this ecological deficit is equal to 116,242,000 hectare or 3.07 times the total
land area of Japan. This becomes 9.2 times the land area of Japan if only habitable land is
taken into account (excluding mountains, water bodies etc.)
The effects of urban activities have in many cases outweighed the relative advantages of
agglomeration and centrality that they have offered. Thus, along with the benefits of
urbanization come environmental and social ills, including lack of access to drinking water
and sanitation services, pollution and carbon emissions etc. A wide variety of urban problems
can be observed, grouped under two broad contradictive classes, those associated with
poverty and those associated with economic growth and affluence.
Environmental Management of Cities
The World Resources Institute's report, "World Resources 1996-1997" focussed on urban
environments. In its executive summary, the report paints a grim picture of urban
environments " ... Burgeoning cities are expanding into fragile ecosystems ... Cities
sometimes deplete nearby areas of water and firewood, rendering them less
capable of supporting rural populations and thus adding to the pressures for
urban migration. Air pollution already exceeds health standards in many
megacities in developing countries. Sewage and industrial effluents are
released into water-ways with minimal or no treatment, threatening human
health and aquatic life. Some urban environmental problems such as access
to safe drinking water improve with economic growth, while others tend to
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worsen. Thus in the absence of policy reform, stronger institutions, and
enlightened political leadership, economic and population growth in
developing countries in the near term may lead to a deterioration of the
urban environment, both physical and social. Stresses on the global
environment from urban activities are also likely to accelerate. A major
share of greenhouse gas emissions already comes from the use of fossil
fuels in wealthy urban areas, especially in the developed countries."
While laws exist to effect interaction and participation between the various actors involved in
urban growth processes, it is not adequately exercised both on the part of local governments
(sufficient information was not provided), as well as other actors and citizens themselves
(there was no commitment to participate). Information that is shared by the government is, in
many cases, partial or selective. There has, however, been a growing awareness of
environmental problems and its causes and effects.
With a gradual increase in the transparency and openness in the functional organization and
operation of local governments, legislation on information disclosure has been receiving
considerable importance. Basic understanding of environmental management of cities and the
consequent needs of information for decision making processes has also improved.
Community involvement becomes all the more critical when the shortcomings and
weaknesses of local governments to effectively deal with the range of problems are taken into
account. All this has necessitated a hard rethinking and reexamination of the intrinsic and
symbiotic (negative and positive) relationships between human lifestyles and natural
resources that is depended upon.
It is helpful therefore, to look at urban environments from three view points: the natural
environment, the built environment and the socio-economic environment. Natural
environments are essentially resources, processes and effects related to flora and fauna,
human beings, minerals, water, land, air, etc. Built environments are resources, processes and
effects related to buildings, housing, roads, railways, electricity, water supply, gas etc. The
socio-economic environment includes resources, processes and effects related to human
activities, education, health, arts and culture, economic and business activities, heritage urban lifestyles in general. It is the intersection and overlay of these three dimensions that
constitutes an 'urban environment'.
Taking any one dimension at the exclusion of the other two, poses the inevitable danger of
missing the forest for the trees - the interdependency and interdisciplinarity of the three
dimensions have to be fully understood in the development of coherent and sustainable
policies and programmes for the urban environment. This is particularly true with the
multiplicity of actors and activities - there has been a growing realization that state agencies
and activities are, but one part of a spectrum of agencies and activities that are involved in the
urban environment.
Interaction between the different actors at different levels of urban growth processes and
cycles becomes critical to respond to the increasingly complex policy and investment choices
that urban communities face. There are many key points that arise in support of a sound urban
environmental policy. The concept of sustainable development ought to take into account the
needs of future generations in decisions on how and whether to use resources and apply
technologies, through policies, investments and development plans.
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Looking at Cities as Ecosystems
A clear urban environmental policy framework should be delineated, based on natural
ecosystems at national, regional and local levels, as well as on human-environment
interactions. It should take into account the stresses and effects occurring within the urban
arena. A system of prioritization has to be put in place, which incorporates human life, health,
depletion and productivity of resource stocks, capacity of the environment, and systematic
accounting measures.
Environmental policies have to be based on an understanding of the causes of environmental
degradation and of the environmental impacts and cost-effectiveness of solutions, as well as
the uncertainties associated with it. Policies should also contribute to greater public
understanding of environmental issues through more open access to information and decisionmaking process. Operationalizing environmental policies, therefore, require the integration of
many interrelated economic, environmental, social and cultural factors.
Table: Resources, Processes and Effects of Urban Ecosystems
Resources










Human Resources
Sunlight
Land
Water
Minerals
Electricity
Fuels
Finance
Intermediary products
Recyclable materials
Processes







Manufacture
Transportation
Construction
Migration
Population Growth
Residence/Living
Community Services
(Education, Health
etc.)
Effects

Negative Effects Pollution - air, water,
noise Waste Generation garbage, sewage
Congestion, overcrowding

Positive Effects
Products, Value-addition,
Increased knowledgebase/
education, Access to better
services
Consolidating the ideas and issues together is the ecosystem approach. An urban ecosystem
brings together the resources, processes and products into a coherent system that exchanges
and makes use of byproducts and/or energy - aiming towards the reduction in the use of virgin
materials as resource inputs; reduction in pollution; increased energy efficiency leading to
reduced energy use in the system as a whole; reduction in the volume of waste products
requiring disposal (with the added benefit of preventing disposal-related pollution); and
increase in the amount and types of process outputs that have market value.
A city must have adequate infrastructure and flexibility to support the needs of its population,
and the needs of the ecosystem as a whole. As in the case of the global system as a whole,
cities must not use resources faster than they can be replenished or substituted for, nor
generate pollution faster than it can be assimilated. One of the guiding principles for the
future will be to reform urban systems so that they mimic the metabolism of nature. Rather
than devouring water, food, energy, and processed goods, and then belching out the remains
as pollutants, the city could align its consumption with realistic needs, produce more of its
own food and energy, and put much more of its waste to use.
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Looking at cities as sustainable ecosystems draws its inspiration from the cyclical ecosystems
of nature itself. It is sensitive to global impacts of local consumption and production patterns,
and takes an interdisciplinary and interlinked approach in developing its activities, outputs
and partners.
BOX: MILLENNIUM ECOSYSTEM ASSESSMENT
The Millennium Ecosystem Assessment (MA) – a multistakeholder international effort – is a four-year process
designed to improve the management of the world’s natural and managed ecosystems by helping to meet the
needs of decision-makers and the public for peer-reviewed, policy-relevant scientific information on the
condition of ecosystems, consequences of ecosystem change, and options for response. The MA will provide
information and also build human and institutional capacity to provide information.
More specifically, the MA will, among other outputs, significantly increase understanding of the linkage
between ecosystems and the goods and services they provide, build human capacity and capacity of global,
regional, national and local institutions to undertake integrated ecosystem assessments and act on their findings,
strengthen international environmental agreements and improve environment-related decisions of national
governments by improving access to the best scientific information and support regional, national, and local
integrated assessments that will directly contribute to planning and capacity-building needs.
The MA will provide the scientific underpinning to a wide range of national and international efforts to address
environment and development challenges. These environmental challenges are interwoven, and thus an
integrative assessment process is needed to highlight for decisionmakers the linkages among climate,
biodiversity, freshwater, marine and forest issues.
Source: http://www.ma-secretariat.org/
Developing cities as sustainable ecosystems requires a radical increase in the productivity of
the resources it uses, and the goods and services it produces. This entails changes in both
production, design and technology stretch the utility value of energy, minerals, water, and
other natural resources. Closed-loop systems return every output harmlessly back to the
ecosystem, or become an input to another process. This requires consumption and production
systems that are modeled after the cyclical ecosystems of nature itself.
This clearly needs an objective, multidisciplinary study of urban and economic systems and
their linkages with fundamental natural systems. Research on energy supply and use, new
materials, new technologies and technological systems, and other relevant issues is critical for
a better understanding of the issues involved.
In a broader sense, the ecosystem approach should be applied at all levels of resource
consumption in a city – from building design and construction and its use, to macro scale
issues of urban planning and development, urban management, network and social
infrastructure (roads, electricity, gas, telecommunications, schools, hospitals etc.).
The urban ecosystem approach raises several critical needs:
1. Ecological footprints of cities needs to be identified
Understanding the dependence of urban residents on not only its immediate hinterland, but
also on far away places and resources for its everyday life – i.e. its ecological footprint, will
assist in developing the concept of urban ecosystems – where resources are used, and wastes
and pollution generated. How will the footprint analyses lead to better understanding of urban
ecosystems? What intangible awareness-raising role can it play to induce action among
urban residents? How can better material flows be developed from footprint analyses?
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2. Global trends to develop local environment activities
There is a clear need to link global environmental problems to action at the local level. Most
global problems are in fact a result of smaller, more local actions (for example, increased use
of cars at the local level leading to global warming). Thus, urban ecosystems need to be
understood keeping global issues and trends in mind. How can this global-to-local
environment continuum be built? What cause-effect cycles can be identified? What
implications do multilateral environmental agreements have in inspiring local action?
3. Partnerships need to be developed among all local actors
Quite clearly, partnerships for managing the urban ecosystem are complex - it is not the local
government alone that can solve the problems at the local level. All local actors - businesses,
NGO/NPOs, citizens groups, schools and universities and others - need to be involved in
partnership so that the strengths and capacities of one actor can overcome the shortcoming or
deficiencies of another actor, thus leading to better concerted action. What partnership
dynamics are at play in an urban ecosystem? What resources, skills, and knowledge do these
actors bring to the table? What are the success factors that will build such effective
partnerships?
4. In-depth and intensive scientific research is needed
There is a critical need for in-depth and intensive scientific/technological research on the
ecosystem approach in order to understand the causes and effects of our everyday lifestyles,
and guide policy development for a sustainable city. What are the critical issues that need to
be researched and studied within an urban ecosystem? What lessons can we adopt from
natural ecosystems and cycles to an urban setting? How can a core behaviour change among
urban residents be effected using the ecosystem approach?
5. Existing environmental management functions and actions need to be integrated
Urban design, planning, implementation and management – particularly of infrastructure – is
fragmented and uncoordinated. Quite clearly, the overarching nature of the ecosystem
approach needs to be taken advantage of in enabling an integrative approach to managing the
environment of a city. Where are these points of integration and overlap? What micro (at the
building and community levels) and macro (at the broader city level) issues need to be taken
into account in operationalizing the urban ecosystem approach?
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APPENDIX:
UNEP-IETC's CITIES AS SUSTAINABLE
ECOSYSTEMS (CASE) INITIATIVE
he goal of sustainable cities cannot be reached without developing a more
sophisticated coherent intellectual framework. This framework should support the
development of urban management and planning theories, as well as methodologies
required by “new” urban decision and policy makers and technical experts to assist
them in implementing environmentally preferable processes, operations and technologies. To
this end, IETC has developed “Cities as Sustainable Ecosystems” (CASE). CASE deals with
issues such as the interaction and relationship within and between cities, their impacts upon
the environment and opportunities for all types wastes to become useful inputs. It embraces
the interactions of all urban activity and the environment and how these can be transformed
into a sustainable relationship.
T
While the need for the development of environmentally sound technologies (ESTs) is
paramount, this must be underpinned by the concomitant development of urban
environmental management strategies. Only then will it be possible to generate the wealth
that is necessary for the restoration of the environment and at the same time improve the
quality of life of the citizens of this planet in a sustainable manner. Similarly, without the
research and development of new urban environmental management methods and approaches
there is a danger that the same problems of environmental degradation and ecological
impoverishment will continue. Given that past environmental problems have arisen primarily
because of inappropriate management and lack of understanding of the impact of management
practices upon the environment, it is essential that new management methods are researched
and implemented. Unless cities change their management practices, the resources they expend
on protecting the environment will be wasted. Underlying this dilemma is the failure to
recognize the importance of management in the causation of the problems in the first place
and the continued (and erroneous) belief that “techno-fix” and the “end-of-pipe” solutions are
the only and, therefore by default, the most efficient solutions.
CASE is the objective, multidisciplinary study of urban and economic systems and their
linkages with fundamental natural systems. As shown in Figure1, it incorporates, among
other things, research involving energy supply and use, new materials, new technologies and
technological systems, basic sciences, economics, law, management, and social sciences.
CASE provides a conceptual framework upon which understanding, and reasoned
improvement, of current practices can be based.
CASE involves the integration of existing scientific, technological and management
disciplines includes the legal, economic and other incentive systems, methodologies and tools,
and data and information resources by which society provides the necessary and appropriate
support for efforts by individuals and cities to implement the principles of sustainable
development. The urban component of CASE is the implementation of sustainable
development principles in the near term at the city or municipality level. Examples might
include the development of materials databases, based on CASE R&D, which would provide
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simple, easily-accessed rankings of the environmental preferability of materials in traditional
uses.
Figure 1: CASE: A Conceptual Framework
Sustainable
Development
CASE
Urban
Management
Management
Accounting
Planning
Strategy
Design
Tools
Standards
CASE can be broken-down further into two separate sets of activities at the organizational
level:
 “Management” includes the development of competencies, organizations, methodologies,
and rules and tools across the city, which generally improves the city's environmental
performance regardless of specific design and production activities. Examples might
include the development and deployment of green accounting systems, green planning
practices, and green procurement, specifications and standards.
 “Planning” includes the development and deployment of rules, tools, and data sets
intended to directly improve the environmental preferability of policies, planning
processes, design and operation. Examples might include development of process
checklists, and software to be included in GIS and/or CAD/CAP systems. In all cases,
CASE activities require inclusion of life-cycle considerations in the analytical process.
Basic research and development in CASE is necessary to provide the objective understanding
and support required for the integration of environmental considerations throughout the
economy of the city. It is also a necessary prerequisite for the development and
implementation of economically and environmentally efficient regulatory structures, currently
a critical policy deficiency. Related activities include:

Planning and implementing a series of studies to understand and model stocks, flows, and
logistics of material movements throughout city for all major materials, including both
renewables and non-renewables, and wastes.
Environmental impacts and
human/ecosystem exposure data could be mapped onto these models, providing the basis
for developing environmentally preferable processes, and helping the urban and civil
sectors and labour markets adjust to an environmentally preferable world. Such
knowledge is also critical to support the development of valid, efficient, risk- based
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


environmental regulations. Indeed, it is difficult to see how environmental regulation can
be effective in the long term without such data and models.
Developing an integrated approach using Environmental Risk Assessment (EnRA) and
Environmental Technology Assessment (EnTA) models of energy production and use,
water usage and conservation, waste production and disposal, and transportation systems.
These models can be linked where feasible to technology, demographic and other systems,
with risk assessment and technology option overlays. As above, this will facilitate the
identification of optimal national and local strategies and programmes to produce
environmentally and economically preferable (and, hopefully, eventually sustainable)
energy, water, waste, transportation, and other EST systems.
Developing integrated models of urban communities, including small relatively selfcontained cities, larger cities with surrounding suburbs, and large megalopolises with
decayed centres and most business activity decentralized throughout the suburbs. Such
models would include transportation, physical infrastructure, food, energy and other
systems. This would facilitate identification of major sources of environmental impacts;
patterns of activities, which give, rise to them, and potential environmentally preferable
EST or mitigation options.
Developing integrated models of specific urban sectors of particular economic,
environmental, or cultural importance - including, for example, agriculture, forestry, waste
and water management - which could then be used to understand how they might be
affected by an increasingly environmentally sensitive world. Such an approach could be
particularly important in mitigating potential economic and employment shocks of
discontinuous environmental, and/or related economic and regulatory, changes, and in
supporting the continuous improvement in quality of life while reducing attendant
environmental impacts.
One of the hypotheses of CASE is that rapid evolution of environmentally sound
technological (EST) systems is a prerequisite for improvement of quality-of-life in an
environmentally sensitive world. The fundamentals of technological evolution and diffusion
throughout the economy are, however, poorly understood. Even less is known about the
optimum, or maximum, rates of technological evolution, the associated economic and labour
costs and benefits (and how they could be optimized), and how such variables differ by class
of EST. (For example, it is apparent that moving to a solar-hydrogen based energy economy
will be significantly more difficult, and a far more lengthy process, than substituting for CFCbased cleaning systems in electronics manufacture.) The CASE approach to such issues may
well produce valuable insights into:



Investigating the interdependency of legal, economic, cultural, scientific and technological
activities and policies as they affect environmental protection and the evolution of EST
systems.
Different regulatory tools and approaches in terms of how cities and citizens behave.
Developing efficient public environmental management structures that support the
adoption of appropriate EST systems.
CASE can provide information that can assist in the prioritization and reordering of
environmental values, both among themselves (e.g., is ecotoxicity, human carcinogenicity, or
global climate change more important?) and in the broader context of other social values (e.g.,
employment, private property rights).
While it is doubtful that an unambiguous,
uncontentious prioritization of values is possible, some broader consensus is necessary to
provide support for further progress. How, for example, can an urban planner be expected to
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design a "green" residential area when what is environmentally preferable cannot be made
clear? This is not a trivial task. It requires the development of comprehensive environmental
risk assessment (EnRA) methodologies, which evaluate and balance risks and possible
benefits on a systems-wide basis.
Clearly, cities are able to develop on their own the overarching legal, regulatory and
economic incentive structures, which will be necessary to support the integration of
environment into all urban activity. They are also able to restructure existing regulatory
systems - including environmental and other related regulatory regimes as consumer
protection and government procurement - so that they avoid unnecessary interference with the
achievement of environmental quality while still meeting their original objectives. Similarly,
in a world where environmental perturbations are not restricted to political boundaries, it is
obvious that the CASE programme, and others like it around the world, must be linked
together in a collaborative international network. Existing international organizations, both
quasi-governmental and private, must assume increased responsibility in this area and
proactively support the integration of science, technology and environment in all urban
activities.
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