If an (open, nonequilibrium) ecosystem receives a boundary flow of energy from its environment, it will use what it can of this energy, the free-energy or the exergy content, to do work. The work will generate internal flows, leading to storage and cycling of matter, energy, and information, which move the system further from equilibrium. Self-organizing processes get started. This is reflected in decreased internal entropy and increased internal organization.
The open question of this section is which of many possible pathways will an ecosystem take in realizing its three forms of growth? The answer given is that an ecosystem will change in directions that most consistently create additional capacity and opportunity to achieve increasing deviation from thermodynamic ground, that is, the exergy stored in the ecosystem will increase. Abundant and diverse living biomass represents abundant and diverse departure from thermodynamic equilibrium, and both are captured in this parameter. If multiple growth pathways are offered from a given starting state, those producing greatest exergy storage will tend to be selected, for these in turn require greatest energy dissipation to establish and maintain, consistent with the second law. Energy storage by itself is not sufficient, but it is the increase in specific exergy, that is increased exergy/energy ratio, that reflects improved usability, and this represents the increasing capacity to do the work required for living systems to continuously evolve new adaptive 'technologies' to meet their changing environments.
These considerations lead to a thermodynamic hypothesis which is able to explain the growth and development of ecosystems and the reactions of ecosystems to perturbations: ''If a system receives an input of exergy, it will utilize this exergy after the maintenance of the system far from thermodynamic has been covered to move the system further from thermodynamic equilibrium If more than one pathway to depart from equilibrium is offered, the one yielding the most gradients, and most exergy storage (dEx/dtis maximum) under the prevailing conditions, to achieve the most ordered structure furthest from equilibrium, will tend to be selected.''
Just as it is not possible to prove the first three laws of thermodynamics by deductive methods, so can the above hypothesis only be 'proven' inductively. In the next section we do examine a number of concrete cases which contribute in a general way to the weight of evidence in favor.
This tentative law may be considered a translation of Darwin's theory into thermodynamics. Exergy measures survival: the biomass and the network, information, and organization that imply that the resources are used in the best possible way to gain most survival. The question is which of the possible combinations of properties by the entire spectrum of organisms in an ecosystem will be able to store most exergy (obtain most survival)? The organisms with the properties that make it possible to gain most survival (exergy) will win in accordance to Darwin and in accordance to the tentative fourth law of thermodynamics. Notice that the resources are always limited relatively to the number of possible offsprings. Therefore there will always be a competition about the resources -and this competition explains together with the huge variation of properties even by the same species, that an evolution has taken place.
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Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.