可以肯定地说，目前描述生态系统的模型没有一个是正确的，只能说是有用的。这是因为下面这个问题远没有解决：We often use ODE model dx/dt = f (t,x,p,u) to express an ecosystem. Based on ecological thermodynamics, the evolution of an ecosystem, dx/dt = f (t,x,p,u), is the gradual complication of its dynamical mechanism f (t,x,p,u) by use of free energy (solar energy), until f (t,x,p,u) can make dx/dt = f (t,x,p,u) have maximal exergy to do maximal eco-work under the prevailing conditions. Hence my question is mainly what form of f (t,x,p,u) can give ecosystem maximum  exergy or work capacity. The exergy embodies the ability to do eco-work for acclimation, and does not equal to biomass. For example, although the elephant’s biomass is much larger than human being’s biomass, the former’s exergy is much less than the latter’s, since human beings have more complicated body structures ‘f (t,x,p,u)’ to deal with information and take action which dissipates the stored-energy to produce dx(t)/dt for changing behaviors and functions to resolved problems for survival and development.

Except for parameter (p) variation, we cannot directly change the analytic formula of f (t,x,p,u) to alter dynamical mechanism to express ecosystem evolution. If we can establish relations between p and x, however, it can alsoindicate the f (t,x,p(x),u) complication, x is equivalent to feedback ecological information.

This inner information network p(x) is far more complicated than trophic network, and hardly ever constrained by matter and energy circulation.

Based on ecological thermodynamics, I want to formulate a reasonable f (t,x,p(x),u) to represent the ecosystem having maximal exergy which is the direction ofevolution. I hope a criterion on exergy variation can be obtained, even don’t solve the ODE model dx/dt = f (t,x,p(x),u) at all.

这个问题，让我苦思冥想，百思不得其解！有同道中人给我指点迷津吗？