Spatial systems approach to sustainable development: A conceptual framework
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RESEARCH Spatial Systems Approach to Sustainable Development: A Conceptual Framework WEN-YUAN NIU JONATHAN J. LU* ABDULLAH A. KHAN Center for Ecoenvironmental Sciences Academia Sinica Beijing, China and University of Northern Iowa Department of Geography University of Northern Iowa Cedar Falls, Iowa 50614-0406, USA
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ABSTRACT / Even though "sustainable development" seems to have emerged as the development paradigm of the 1990s, a great deal of vagueness still surrounds the meaning, definition, and theoretical underpinnings of the concept. There is also a general lack of emphasis on the spatial dimension of sustainable development when developing relevant conceptual or environmental accounting frameworks. In clarifying the concept, this article proposes a definition that explicitly incorporates the
Sustainable development has become a topic of great interest in recent years and there has been a steady proliferation of literature on the subject (e.g., Clark and Munn 1986, Repetto 1987, Redclift 1987, WCED 1987, Timberlake 1988, MacNeill 1989, Reid 1989, Adams 1990). Ruckelshaus (1989, p. 167) noted that sustainability is an emerging concept that presupposes economic growth and development must take place, but it should be a complementary rather than antagonistic process with environmental protection. T h e World Bank and other international development agencies and institutes took this concept very seriously and seem to have adopted sustainable develo p m e n t as their guiding principle (Goodland 1990, World Bank 1989, El Serafy 1988, WRI and others 1988, Daly and Cobb 1989). Indeed, L616 (1991, p. 607) suggested that sustainable development is KEY WORDS: Development; Environment; Environmentalaccounting; Resource; Spatial System; Sustainability;Sustainabled#velopment
*Author to whom correspondenceshould be addressed.
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temporal as well as the spatial dimension of sustainability. It also develops a logically consistent conceptual framework for the analysis and evaluation of sustainable development, following a spatial systems approach. Five interconnected aspatial subsystems or subsets of a spatial system are identified and their respective operational dimensions discussed. A proposed composite index called degree of stainable development (DSD) and its five component indicators are also outlined. The difficulties involved in operationalizing the DSD measure and the conceptual framework are noted, and the various tasks that need to be undertaken in this regard are specified. It is concluded that future research utilizing the proposed conceptual framework should not only foster the development of appropriate methodologies for the comparative evaluation of sustainable development at global, national, or regional scales, but also offer insights to appropriate decision makers at various levels regarding available options and alternative actions for the healthy development of their respective societies.
"poised to become the development paradigm of the 1990s." However, there seems to be no consensus about tile concept of sustainable development. Despite the existence of extensive reviews of literature (e.g., L616 1991, Tisdell 1988, Barbier 1987, Brown and others 1987, Redclift 1987), sustainable development remains a rather vaguely understood idea (L616 1991, Redclift 1991, Barbier and others 1990). Redclift (1991, p. 36) noted that the problem with the concept of sustainable development is that it "means different things to different people." T o some extent the value of the phrase does lie in its broad vagueness, but murmurs of disenchantment are also being heard (L616 1991). It has been suggested that sustainable development is in real danger of becoming "a cliche like appropriate technology," "a fashionable phrase," "the latest development catchphrase" (L616 1991), "an article of faith," or "a shibboleth" (Tolba 1984). This is certainly not a very happy situation, particularly if sustainable development is to become a meaningful paradigm of development. Another related and perhaps more important problem is that even though both the temporal and
9 1993 Springer-Verlag New York Inc.
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spatial dimensions of development are implicit in the concept, the latter is seldom given due emphasis in pertinent literatures. In today's world of proliferating nation states and national boundaries on the one hand, and the interdependent and increasingly integrated global economy on the other, the importance o f the spatial dimension vis-h-vis environmental issues can no longer be ignored. Many conflicts and disputes of the contemporary world relates to the fact that while activities of a region or country may not deplete resources or cause environmental problems locally, they may destroy the resource base or contribute to environmental degradation in another country or region. Examples may be cited from the regional consequences of acid rain in North America and Europe, downstream consequences o f water diversion projects in the Ganges Basin of South Asia, or potential global consequences o f the destruction of the rainforests in Brazil's Amazon Basin. Despite the general awareness, the sustainable development literature, unfortunately, tends to overlook this important spatial dimension. Furthermore, the underlying conceptualtheoretical frameworks often treat the earth as if it was comprised of many disjointed or closed national systems. For example, in a recent conceptual article regarding the multiple dimensions of sustainable development, Redclift (1991, p. 39) emphasized only three dimensions (economic, political, and epistemological) that require our urgent attention; the spatial dimension was left out. Even though there are some references to "groups of people whose environmental practices are threatened by outsiders" (emphasis added), and to a "North/South framework" for considering sustainable development, Redclift (1991) and others essentially ignore the need for developing a spatial framework for environmental accounting. Hence, the purpose o f this article is twofold: (1) to clarify the concept of sustainable development and to propose a definition that explicitly incorporates the temporal as well as the spatial dimension of sustainability; and (2) to develop a logically consistent conceptual framework that would foster the development o f appropriate methodologies for the comparative evaluation of sustainable development at global, national or regional scales.
Clarifying the Concepts Development T h e term development has been defined as the process o f directed social change. Such a definition stems from the normative perspective of social science,
which makes an important distinction between development and growth. Development is seen as the active component in social forces that determine social change, which would otherwise occur in a relatively passive way through growth (Sharma 1984). Social change is defined, necessarily, in the broadest terms to incorporate changes in the economy and the polity. T h e World Commission on Environment and Development (WCED 1987) suggests that satisfaction of human needs and aspirations is the major objective of development, which involves a progressive transformation of economy and society. It should be noted here that although development is frequently defined in terms of economic growth, the concept indeed goes much beyond the sphere of pure economics to incorporate concerns about "human needs and aspirations" and "transformation o f society" (Carstairs 1990). Further, Daly and Cobb (1989) have suggested that development should refer to the qualitative change of a physically nongrowing economic system in dynamic equilibrium with the environment. Going a step further, we include both economy and environment as components in a holistic spatial system and, following Niu (1989a), define development as a dynamic process within a complex physical-societal system, leading toward a more harmonious, complementary, and equilibratory state as a consequence of directed social change. Such a conceptualization must take into consideration quantitative and qualitative, as well as temporal and spatial, aspects of development. Here, we treat development as a positive and beneficial process, but one that is also capable of generating negative externalities. Thus, the understanding of the development process requires the evaluation of the process at different spatial levels and in relation to the characteristics of the different stages o f the development continuum. In this context, we classify human history into four stages o f development, namely, predevelopment, underdevelopment, upperdevelopment, and sustainable development. T h e spatial context, as well as the respective characteristics o f these stages of development, are identified in Table 1.
Sustainable Development As indicated in Table 1, the last stage in the develo p m e n t continuum is deemed to be sustainable develo p m e n t - - a stage that, it is hoped, humankind is approaching. Recently, L616 (1991) detailed a discussion on some conceptual and semantic problems associated with various interpretations o f sustainable development. In it, he refers to a "mainstream" formulation of sustainable development, based on the definition adopted by the World Commission on Environment
Sustainable Development Framework
Table 1. Classification and characteristics of the development continuum Attributes
About 10,000 years ago
After industrial revolution (c. 1700 to present)
Spatial scale Philosophical thinking Attitude toward nature Level of economy
Individuals or tribal area Indifference Coping with nature Rudimemary (in natural food chain)
After agricultural revolution (10,000 years ago to now) Regional or national What is it? Parmering nature Primary (agricultural activities dominant)
Nature of economy
Gathering and hunting
Strnctural natural system
Nonstructural man-land system Basic needs for living
Functional. complicated natural economic system High-level aspiration
From hands to mouth
Animal, wind, and/or water
Greater environmental impact on marl
Slow degradation of environment
Short-term pollution and lung-term environment deterioration
After iuformation revolution (c. 1980 to present) Continental or global What will happen? Harmony with nature Qnaternary~tuiuary (decision making and controlling activities dmninant) Coordinated growth economy Controlling complex, physical-societal system Compromise for ecological balance Balanced and recycling reproduction Sustainable consumption for different generations Develo[nnenta[ and substitutional energy Harmony with environment through waste management and recycling of resources
and Development (WCED). The WCED (1987, p. 43) defined "sustainable development" as "development that meets the needs of the present without compromising the ability of future generations to meet their own needs." The significance of the WCED Report lies in that: (1) it gives sustainable development both a philosophical concept and a social objective, (2) it gives us a prudent and optimistic vision of our future rather than pessimistic predictions of doom, and (3) it provides the basis for developing specific objectives and operational measures of sustainable development. The WCED report, however, emphasizes only the temporal dimension of sustainable development and largely overlooks the spatial dimension. As noted earlier, in today's interdependent world, it is important to consider explicitly that activities of a region or country not only deplete resources or cause environmental degradation locally but also frequently destroy the resource base of another region or country. This is an ethical as well as a potentially conflict-generating issue that must be incorporated in any realistic environmental accounting for sustainable development. It follows logically that we should propose an extended definition of sustainable development that meets: (1) the needs of the present generation without compromising the ability of future generations to meet their own needs; and (2) the needs of a specific region without curtailing the ability of other regions to meet their own needs.
National or continental Why is it? Contrnlfing nature Secondary-tertiary (industrial and service activities dominant)
The Proposed Conceptual Framework Given the above definition, our proposed conceptual framework for the analysis and evaluation of sustainable development follows a spatial systems approach. In this context, a spatial system refers to a complex physical-societal system, which has a distinct geographic space with specific boundaries (either natural or artificial). The scale of spatial systems may vary widely, ranging from local to global, thereby giving rise to nested hierarchies of spatial systems. According to our conceptual framework, as summarized in Figure 1, a spatial system comprises five interconnected aspatial subsystems or subsets with respective operational dimensions. These are: (1) life-support subsystem (per capita carrying capacity of resources), (2) well-being-support subsystem (productivity of the economy), (3) process-support subsystem (stability of development), (4) environmental-support subsystem (assimilative capacity of the environment), and (5) intelligence-support subsystem (adjustability of management). These subsystems and their corresponding operational dimensions are important elements in analyzing sustainable development at different spatial levels--local, regional, national, or global. In analyzing sustainable development from a spatial systems perspective, our main concerns are with determining: (1) a balance between supply and demand for meeting basic present needs and [uture as-
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I Sustainable Development I
I The Spatial System I I
Li~e. Support :~uDsystem Carrying Capacity of Resources
Subsystemsof the Spatial System
T Well-being H Support
t ProceSs Support
I Environmental Support
Productivity of the Economy "
Stability of ' Development - -
Assimilative Capacity of the Enwron. m
Intelligence Support Subsystem Ad3ustability of Management
Operational Dimension of the Spatial System
1 Measurement of Sustainable Development Ability
l I Five Indicators The
J Richness .esourcesof
] J the -'treng t"~ Economy
I Stability Societyof
ITqlerability of I the tnviron, I
I Soundness of Decision I
Degree of Sustainable Development I (Expressed in Probability)
, DSD < 0.59 Non-sustainable Dev.
J DSD > 0.59 < 0.70 J Weak Sustainable Dev.
Strong Sustainable Dev.
Deriving Optimum Compromise
pirations, (2) an appropriate ratio between consumption and capital investment at a given level o f GNP, (3) the direction, intensity, and pattern of interaction among the five aforementioned subsets, (4) the ability to adjust and control this enormously complex system, and (5) the mathematical solutions relating to the five interacting subsets of operational dimensions. All these tasks should be undertaken within the bounds of the "normal cycle of sustainable development," as conceptualized in Figure 2.
Figure 1. A spatial systems frameworkfor evaluatingsustainabledevelopment.
Operational Dimensions of the Spatial System
Carrying capacity of resources. Carrying capacity is the operational dimension of the life-support subsystem, and it refers to the size of population, human and otherwise, a given environment can support. As to the concept of resources, it has two components: (1) a quantitative component, which includes renewable and nonrenewable resources; and (2) a qualitative component, which is the total natural surroundings, within which all the living things can function without
S= Supply Demand= D T = Technology Management= M R=Recyde Affect = A r = Reuse Discard= d Figure 2. T h e normal cycle of sustainable development.
Sustainable Development Framework
feeling pressure or stress. T h e f o r m e r is necessary to provide basic means of production; the latter is necessary to maintain a stable environment to foster the continuation o f the biosphere. Hence, in our conceptualization, the carrying capacity of resources depends on the availability of different categories of resources, the amount of each category, the combination of all resources at a particular spatial level, the accessibility to these resources, the exploitation cost, the technological level, and the substitutability of regional resources. Productivity of the economy. This relates to the wellbeing-support subsystem and refers to the ability of an economy to qualitatively and quantitatively change the resources from their original state of raw material and energy to products that can be used or consumed, thereby enhancing the general well-being of the population. Productivity can be conceptually expressed as a function of resources, capital, labor, technology, management, and time. O f these, technology is considered to be the key factor because ultimately it is improvements in technology that contribute the most toward raising the level of productivity over time. Stability of development. Stability of development is defined here as the ability to keep the behavior of the economy within an acceptable amplitude. Such stability includes: (1) physical stability, which takes into consideration oscillations in the natural environment and implies such actions as appropriate adjustments to natural hazards; (2) economic stability, which includes structural, functional, and supply-demand stabilities; and (3) sociopolitical stability, which calls for a just and equitable system with minimum possible social and political conflicts. Indeed, stability is a necessary condition for the development process, and it is the essence of what we call the process-support subsystem. Assimilative capacity of the environment. T h e capacity referred to here is the operational dimension of our environmental-support subsystem, and it represents a threshold value by which we may determine if the u p p e r environmental tolerance limit is overtaxed. Once the environmental capacity has reached its upper tolerance and is overtaxed, the primary productivity of the biosphere and living beings would suffer reversible or irreversible consequences. It ought to be mentioned here that environmental consequences of development efforts seldom remain confined within the spatial systems where the projects are located, rather they spill over to neighboring systems. Hence, assimilative capacity must be determined in relation to an appropriate "spatial horizon," much the same way as the "time horizon" is taken into account in costbenefit analysis.
Adjustability of management. In sustainable development, adjustability means that the integral effect of the system can be changed by deliberately controlling or managing some of the elements of this complex physical-societal system. T h e effectiveness of such management depends on accumulated knowledge and intelligent manipulation. Adjustability of management thus relates to our intelligence-support subsystem, and it represents a test o f the flexibility o f development strategies, policies, and actions. It should be emphasized here that the subject of sustainable development is as much concerned with the issue of ethics and our ethical sensibilities as it is with the question of how much we can get away with, given the limits of natural systems. T h e r e f o r e , ethics and ethical choices must be important considerations in developing and implementing environmental management strategies for sustainable development. T h e conceptual mode[ o f sustainable development comprising the five basic subsets discussed above, is intended to be flexible so that it can be easily adapted to various geographical scales and/or regions with a wide range of physical-societal characteristics. Niu and Yue (1990) have applied a similar model to a theoretical study of complex agroecosystems. Measuring Sustainable Development In operationalizing the proposed model, we need to establish a set of indices to measure sustainable development. Recent research has pointed to the need for a more comprehensive measure of sustainable development that will provide better guidance than those presently available. Such a measure should ideally be able to improve judgement, comparison, and forecasting of sustainable development on a universal basis. A n u m b e r of indices have already been developed that purport to assess quantitatively the situation relative to sustainable development (Nordhaus and Tobin 1972, Zolotas 1981, Daly and Cobb 1989, E! Serafy 1988, Ahmad and others" 1989). Following these earlier works, and utilizing relevant theoretical-methodological concepts, we propose to construct a more sophisticated index, with much broader scope, which would be called degree of sustainable development (DSD). T o calculate DSD, we need to derive a set of indicators pertaining to the five component subsystems of the spatial system and their respective operational dimensions, as described earlier in Figure 1. T h e proposed indicators are as follows: 1.
An indicator of richness of resources, linking the carrying capacity of available resources with population size and composition.
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An indicator of strength of the economy linking productivity with capital, resources, and technological progress. An indicator of stability of society, linking the development process with rationality and societal equity, and with environmental regularity and perfectivity. An indicator of tolerability of the environment, linking the assimilative capacity of the environment with short- and long-term ecological effects, both within and outside the spatial system. An indicator of soundness of decision making, linking management with flexibility, adjustability, and environmental sensibility.
In terms of the conceptual derivation of DSD, the five indicators noted above need to be operationalized in terms of specific variables, and then, using an appropriate weighing scheme, these may be combined to generate the composite DSD index. T h e selection of the specific variables should ideally be general enough to allow comparative evaluation, but there should also be provisions for reasonable modifications during the process of operationalization to suit empirical conditions in particular spatial systems. In this context, we recognize the extreme difficulties involved in measuring sustainable development even in terms of the five categories or sets o f variables as proposed here. For instance, there is the question of how to get the first number for each of the categories even before the DSD is calculated. Moreover, there is also a central issue in the debate over sustainability measurement that concerns the p r o p e r balance between what concepts we want to measure and what measures are feasible. Assuming that we are able to resolve these difficulties, and that we are able to calculate the DSD values, these values then should provide an assessment of the extent of sustainable development in a spatial system. In our continuing exploratory work, we have determined that the DSD can be expressed in probabilistic terms. For instance, in relation to our conceptual model (Figure 1), a DSD probability value of 0.59 may represent a threshold, and if a DSD value is equal to or greater than 0.59, then sustainable development could be maintained. However, when a DSD probability value is between 0.59 and 0.70, it could only be considered a "weak" sustainable development. If a DSD probability value is greater than 0.70, it would then represent "strong" sustainable development.
Deriving Optimum Compromise T h e most important feature of achieving sustainable development is the art of compromising. Com-
promise of different components is usually controversial in a complex physical-societal system. However, compromise is essential to obtain a better "integral effect" in the system. T h e so-called compromise usually is understood to be a macroscopic optimization of the complex system, or in simpler terms, the tradeoffs between the critical components of the dynamic physical-societal system. No doubt, some of these compromises or trade-offs would be already determined in tile calculation of the DSD value itself. More importantly, however, optimum compromise pertains to the goal of attaining and maintaining a stage of development that is sustainable. Given the degree of sustainable development of a particular spatial system, as determined by the DSD index, the policy makers would need to make certain compromises in formulating their developmental strategies and programs. In relation to our conceptual framework, we group these essential optimal compromises into four major categories: 1. Optimum compromise between economic growth rate and environmental protection level. In our judgment, this compromise can be derived by using the basic principles of game theory (O'Sullivan 1981, Niu 1989a). 2. Optimum compromise between the needs o f the present and the future generations. Niu (1989a) has demonstrated the operationalization of this idea with equations showing a rational "distribution of natural resources between generations." With further refinement, Niu's idea and equations can be employed to optimize a compromise between generations for sustainable development. 3. Optimum compromise between consumption and capital investment at a given level of GNP. El Serafy (1988) has examined this same issue in a recent publication, and his method can be conveniently adopted for the present purpose. 4. Optimum compromise between the interests o f an empirical region (spatial system) and those of other pertinent regions. In our proposed conceptual framework, sustainable development has an explicit spatial dimension, and it is emphasized that we should look into not only the temporal, but also the spatial aspect of system equilibr i u m - - a dynamic equilibrium among different regions or nations. It is our targeted goal to be able to derive appropriate guidelines for achieving such global stability and harmony vis4t-vis sustainable development. Once the goals of resolving these four optimum compromises have been attained, we could hope for
Sustainable Development Framework
sustainable development to be successfully achieved and maintained. No doubt, however, a great deal of work (research, deliberations, and international cooperation) lies ahead before such optimistic goals could be realized.
Monitoring Sustainable Development: The Tasks Ahead In o r d e r to develop operational strategies to help nations move toward a direction of healthy socioeconomic development, it is necessary to discern and diagnose their status vis-a-vis sustainable development. Central to such research is the design of a generally acceptable theoretical-conceptual framework and standard yardsticks for evaluating and comparing sustainable development on a global basis. T h e framework should also systematically provide some analytical or mathematical models to substantiate or enrich the theory of sustainable development. In other words, we need to establish a global sustainability related information and analytical system to gauge, compare, monitor, and predict the status o f sustainable development. T o do this, we have to undertake the following tasks: Set up a sustainable development database involving different spatial levels (i.e., local, regional, national, global), in keeping with our theoreticalconceptual framework; 2. Devise specific measures for the purpose of determining different kinds o f initial values, critical values, and boundary values pertaining to the DSD index discussed earlier; 3. Gauge whether a nation is at the threshold of sustainable development; if not, what is the extent of its deviation from the threshold, and how can it be raised to the level of sustainability; 4. Compare sustainable development status o f different nations and arrange them in p r o p e r orders according to their position on the global sustainability spectrum; 5. Generate a list of adjustable or controllable alternative measures and prioritize the appropriate actions, which will keep a spatial system at a p r o p e r stage of sustainable development; and 6. Develop a set of appropriate guidelines or broad strategies for global sustainable development.
effective means for organizations such as the World Bank and other international development agencies to improve their judgement, assessment, and response ability. T h e results of future methodological and empirical research utilizing the proposed conceptual framework should aid in the development of sustainable systems to keep the world in a rational, equitable, and stable state of development. In addition, the sustainable development framework should offer insights to leaders at regional, national, and global levels for making decisions regarding available options and alternative actions for the healthy development of their respective societies. T h r e e major impediments to the attainment o f sustainable development do, however, continue to exist: (1) inadequate understanding o f the meaning, definition, and theoretical underpinnings o f sustainable development; (2) unidentified elements, dimensions, and relations o f sustainable development; and (3) uncertain strategies and seemingly incompatible national interests to guide the behavior o f sustainable development programs. When the effects o f these constraints are eliminated or minimized, a research framework can be successfully transformed into an operational and realistic planning tool. It is toward the realization of this aspiration that the present article is devoted.
Conclusions Developing a global sustainable development evaluation framework is r e c o m m e n d e d in this article as an
Acknowledgments T h e authors wish to acknowledge the helpful comments by two anonymous referees and a n u m b e r o f colleagues on earlier drafts o f this article.
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