Weak and Strong Sustainability Indicators, and Regional Environmental Resources
1 Introduction
Many attempts to operationalize the ecological concept of sustainability have been under-
taken by the economics profession during recent years. It seems that many mainstream
economists tend to focus their research on the assumption of substitutability between man-
made (manufactured) capital and natural capital (natural resources, goods and services). The
crucial points of this discussion can be seen especially in contributions by Solow (1993) on a
more theoretical level and by Pearce and Atkinson (1993) on an empirical level who all plead
for at least partial substitutability. As Daly (1992) has pointed out, the assumption of substi-
tutability cannot be drawn in the search for an adequate treatment of natural resources in eco-
nomic and ecological modeling and policy.
The paper tries to clarify some questions regarding weak and strong sustainability indicators
as well as sustainability rules for dealing with regional natural resources.
In the first part of the paper, the assumption of substitutability is discussed in various as-
pects. Given weak sustainability indicators, calculating the „sustainability“ of a regional sys-
tem (or national economy) becomes almost trivial. If the rate of depreciation of natural capital
is at least offset by savings (accumulation) of man-made capital then the economy is on a sus-
tainable development path. Besides the missing of the social „branch“ of sustainability, the
depreciation-savings approach lacks understanding of the fundamental objections against
monetizing natural resources (e. g. biodiversity). Some crucial aspects in this context are dis-
cussed in the paper (e. g. lexicographic preferences, „consumer“-vs.-„citizen“ approach).
The strong sustainability indicators are in favor of different approaches, e. g. the save-
minimum-approach. The second part of the paper deals with practical sustainability rules on a
regional level regarding water resources. If sustainability as a concept for future ecological,
economic and social development is taken seriously, only physical constraints (taking time as
an additional factor of production into account) and an applied precautionary principle can
indeed lead to sustainability.