Sentence:  The succession of associations leading to a <WSD>climax</WSD> represents the process of adjustment to the conditions of stress, and the <WSD>climax</WSD> represents a condition of relative equilibrium. <WSD>Climax</WSD> associations... are the resultants of certain climatic, geological... conditions. 
Meaning of the word marked with <WSD> tags:  (ecosystem)  The culmination of ecological development, whereby species are in equilibrium with their environment.