|Industrial Metabolism: Restructuring for Sustainable Development (UNU, 1994, 376 pages)|
|Part 2: Case-studies|
|8. Industrial metabolism at the regional and local level: A case-study on a Swiss region|
One of the most outstanding features of modern man is the capability to exploit, refine, and consume large masses of raw materials. During the development of mankind from neolithic tribes to highly structured urban societies, the total flow of goods used to support human activities increased by two orders of magnitude (fig. 1). Today, in densely populated areas, the fluxes of many anthropogenic materials surpass natural material fluxes. The main reason for this result is the continuous development of the art and technology of prospecting, extracting, upgrading, and designing new and existing materials. In addition, the population growth of the last few centuries has accelerated the flux of anthropogenic materials (fig. 2).
The huge increase in the consumption of goods has several implications: On one hand, it causes a quantitative problem, since the large mass of used goods has to be recycled or disposed of as waste, and thus financial and natural resources (land, water, and air for dissipation) are required for its management. On the other hand, there is a qualitative challenge: the growth in the consumption of materials such as heavy metals or organic compounds leads to large stocks of potentially hazardous materials in the anthroposphere, and to increased fluxes of materials detrimental to the environment. The data contained in figures 1 and 2 show that the consumption of total goods has increased by about two orders of magnitude, and that the consumption of many trace materials such as lead has increased by six and more orders of magnitude. Thus, it may be concluded that the past growth in the material fluxes is mainly of qualitative and secondarily of quantitative importance.
The major goal of environmental protection and waste management is to reduce the material flows at the anthroposphere/ environment interface to sustainable levels. Of the many questions which are still unanswered, the following two seem to be fundamental: (1) What are sustainable levels? (2) How can we reach these levels most efficiently?
Despite the lack of answers, decisions have to be made today about the control of material fluxes. In this situation of uncertainty, a cautious approach is appropriate. A conservative concept may be based upon the comparison of anthropogenic and geogenic fluxes: it can be postulated that anthropogenic material fluxes are sustainable for natural systems if they do not change geogenic concentrations, fluxes, and reservoirs. Thus, the goals for the management of material fluxes from the anthroposphere to the environment (in the past often subdivided into "water-pollution control," "air-pollution control," and "waste management") must be to reduce anthropogenic fluxes to levels that allow natural systems to maintain their steady state at geobiogenic levels. This implies that the output of the anthroposphere will become much smaller in the future.
Considering the growth in materials consumption by several orders of magnitude, it will be necessary to reduce the output by more than one order of magnitude for future effective environmental protection. If the input into the anthroposphere is larger than the output, inevitably the stock in the anthroposphere will grow. According to the laws of thermodynamics, it will never be possible to recycle all materials in the anthroposphere. It is essential that the disposal of wastes that leave the man-made system should yield sustainable fluxes only (c.f. waste treatment residues with "final storage quality": Baccini, 1988).
Hence, input, storage, and output of materials in the anthroposphere are interrelated and cannot be controlled separately. Each measure to control the flux of materials has impacts on all three processes. This is true for global, national, and regional economies. In the future, it will be necessary to answer the question of how to control "industrial metabolism" on all levels in view of regionally and globally sustainable fluxes. In this chapter, we will focus on the regional level, which is the level where most control decisions are made: cities and communities plan and regulate their anthroposphere; people decide to move to a region; companies are attracted by regional advantages; the specific resources of regions offer particular opportunities, etc.
In order to assess and control regional industrial metabolism, a threestep procedure is proposed. The first - scientific and technical - step consists of a regional material balance. It includes the assessment of imports, exports, and internal fluxes of goods and materials in the anthroposphere and environment, and emphasizes the growth and/or depletion of natural and anthropogenic reservoirs. In the second technical and economic - step, the most efficient means to control anthropogenic material fluxes are determined. The third political and social - step consists of the implementation of the measures to control industrial metabolism.
The emphasis of this chapter is on step 1, and the objective is to present a methodology for the establishment of regional material balances, using a case-study on a Swiss region. The main question is how to determine the important processes and fluxes in a region consisting of thousands of anthropogenic and natural processes. The work focuses on fluxes of goods and includes two examples of materials such as lead and phosphorus. The results are used to discuss part of step 2, means to control selected materials in a given region. Economic, political and social issues (steps 2-3) are not treated here. Although the region investigated is located in Switzerland, and the concepts discussed here have been developed there, we believe that the approach and methodology chosen can be applied anywhere.