Reductions in ecology and thermodynamics. On the problems arising when shifting the concept of exergy to other hierarchical levels and domains

Abstract

The introduction of thermodynamical views to interpret phenomenological behavior of biological systems such as organisms, populations, ecosystems or even the bio- and anthroposphere is not an easy exercise and not carried out without obstacles. The resistance against such an endeavor can be met from all scientific disciplines ranging from hardcore physics at one end to ecological fundamentalists at the other. Thus the area represents a field of tension. The reasons for this may be many, but at the center one will recognize complication that are closely linked – directly or indirectly – to the issues around philosophical reductions undertaken in the process. Such steps are necessary to take in an attempt to formulate a new holistic biological theory that tends to formulate a new metaphysics, namely that of making possible interpretations of all kinds of systems within the biosphere in terms of a thermodynamic framework. Common to all attempts have been the establishing and definition of boundaries – real, physical as well as constructed and virtual – together with a generalized application of isomorphic mathematical expressions used different sets of ontological entities that vary with levels of the biological hierarchy. Prebiotic systems represent the closest we may get to a situation where classical thermodynamic descriptions may be used but still only to a certain extent. All levels having a fixed boundary from monocellular organisms or conglomerates of such systems and upwards in the hierarchy – i.e. higher organisms and levels throughout the biological hierarchy represent systems under conditions so far away from equilibrium that they – under the given energetic, material and intrinsic constraints tend to stabilize at dynamic states or sequential semi-stable repetitive patterns. This means that we may not talk about classical thermodynamics any longer. Terms like entropy, free energy, exergy and power may be used as convenient metaphors, but it must be stated that it as a consequence is necessary to (re-)define concepts and reformulate equations based on adequate ontological units. Although they may perform with a similar phenomenology as the classical variables, it should be kept in mind that they are no longer the same, – each domain will need its own definitions.