ABSTRACT
Can the indicators presented in the preceding chapter measure ecological sustainability? This chapter assesses first the capacity of the natural environment to provide lasting services. None of the indicators of area and energy succeed in measuring comprehensively and unequivocally the depletion and degradation of nature. On the other hand, setting standards or targets for environmental pressures or impacts are judgmental. The flow of materials through the economy has been evaluated by “factors” of natural resource use. Global warming, losses of biodiversity and nitrogen pollution may have transgressed thresholds of an “environmental space,” but other limits of the environment are still unaffected. Global warming, the most frequently used proxy, might increase beyond a tolerable limit of 2 ºC up to 5 ºC by the end of the century. Monetary measures of natural wealth and environmental cost may be easy to aggregate, but are more useful for assessing economic sustainability. Still, the cost of avoiding or mitigating environmental decline gives an indication of what society should and could spend on the preservation of nature; but will it do so?
