Models of physical processes have been part of classical physics since the very beginning of modern science. Especially mechanics, as developed by Galileo and later by Newton, are important starting points for the understanding of how physical processes are understood in an ecological context. Mathematical models of environment-related problems have a long history, but many people refer to Darcy (1856) as the first attempt to understand the physics behind the flow of water. During the last 30 years a number of ecological models have been developed in different contexts that all originate from very fundamental assumptions on a few physical principles. Those that developed and those that are using the models are dealing with processes for transfer of heat and mass. Typical structures for such models were simplified systems in which the geometry was reduced to one dimension and included a homogeneous substrate studied under a simple type of influence. Such simple systems were also studied experimentally to understand the mechanism of transfer. It has been possible to simulate the experimental setup through analytical mathematical models.