FYI for an online, review paper on ecohydrologic complexity:
Rosenfeld, J.S. 2017. Developing flow-ecology relationships: implications of
nonlinear biological responses for water management. Freshwater Biology 62:
Certainly, lack of recognition of curvilinear relationships led to the big,
irrigation-caused fish (salmon/sucker) kills in the Klamath R. in the early
oughts. Fortunately, we headed off a similar problem the Columbia R. soon
thereafter; lack of linearity doesn't mean that water doesn't matter to fishes!
Indeed, WUA curves are typically curvilinear...