Download or read book Eco-Exergy as Sustainability written by Sven Erik Jørgensen and published by WIT Press. This book was released on 2006-02-28 with total page 225 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exergy is the measurement of the amount of work capacity i.e. the amount of energy that can do work. The author applies this concept to ecology, where it can be used as an ecological indicator for ecosystem health assessment and this is presented in the book with illustrative examples. In addition, the question of how it is possible to define a special ecological exergy concept to calculate the exergy for models of ecosystems is covered. The use of exergy and an introduced fourth law of thermodynamics make it possible to understand the ecosystem reactions and how the ecosystem can grow in three different forms - biomass, complexity of network and information. From this analysis, it is clear why ecosystems are sustainable systems and what characteristic properties ecosystems have to ensure that sustainability. A parallel from ecosystems to society makes it possible to formulate the same rules (laws) for society. The concept of exergy as a health indicator measuring the degree of sustainability of society can also be used. Examples will be applied to illustrate the application of exergy and the deduced ecological rules (laws) for understanding the society.