ABSTRACT
Ecosystems are open systems. ey have to receive an inªow of free energy-energy that can do work-to be able to maintain their complex structure. In accordance with the second law of thermodynamics, all dynamic systems will inevitably produce entropy, lose order, and free energy. Ecosystems therefore need an inªow of energy that can do work to combat these consequences of the second law of thermodynamics. Ecosystems are, however, not only physical open but also ontic open. Due to the very high complexity of ecosystems, an uncertainty principle for ecological observations is valid.
