How is the second law of thermodynamics related in ecology?

Answer 1

The second law of thermodynamics can be related to entropy. This means "all natural systems left to their own devices will follow a path of decline or become unorganised".

The reason this relates to ecosystems on earth is because if we do work on a system it can become more organised. Similar to if we were to do work on an object it would gain heat.

The relation to the second law is that natural systems left to their own devices cannot become more organised. Just like heat cannot flow from cold to hot naturally.

Comments: I've corrected some errors in that answer, but it's still a bit unusual and probably needs improving. For example living organisms

obviously can become more organised.

The second law is a bit tricky. Remember it applies to "closed systems". Open systems can be affected by "outside" things such as energy input.

As regards the first law of thermodynamics, that's basically the law of conservation of energy.

So, obviously, ecosystems need an energy source.

Answer 2

Due to the second law of thermodynamics, even "renewable" energy yields a net release of heat to the surroundings. An advantage of renewable energy is that it can be a predictable, sustainable source of energy as opposed to fossil fuels extracted from the ground which apparently take millions of years to create through geological processes.

Answer 3

Briefly, living beings need energy, and their energy gets used up, meaning that although (in the sense of the First Law) total energy is conserved, in the sense of the Second Law such energy is converted from useful energy, to less useful energy.

Answer 4

The first and second laws apply EVERYWHERE, including ecosystems. Specifically, living beings need energy - and that means, usable energy - to live.