Question 64494

I was reading from Odum about Liebig’s law of minimum.
It said that the law is appicable in steady state condition i.i. when the inflow of energy and material balances out the outflow.

I got two questions:
1.Here what is actually in steady state? Photosynthesis? or Plant community? or Biotic community?
2.Inflow of energy and material balances out the outflow. I don’t get this. Can you elaborate this part a bit? What is the net material/energy that is flowing in an out of a system? Could it be amount of light absorbed and amount of glucose and O2 produced? He used the word balances which means they are not equal actually but proportionate I suppose. Am I right?