Ecological sustainability index

Krotscheck C, Narodoslawsky M. The sustainable process index—a new dimension in ecological evaluation. Ecol Eng 1996 6(4) 241—58. 

Each of the sustainability class is assigned depending on the value of the aggregate index— S, on the analyzed level (there are social, economic, and ecologic platform as weU as complex sustainability). Intervals were determined arbitrarily by the authors of the paper based on a universal scale of unity relative states, taking into account the semantic definitions of the state term ... 

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