This diagram is more of an engineer’s view of the food web. I find that it helps to sometimes consider things as just a balance of energy and mass. It all must come from somewhere and it must all go somewhere else. With that in mind, I retrofitted some P&ID figures to represent exchange of energy and mass via the food web. I only went as far as secondary consumers, since adding tertiary consumers would have made the diagram too cluttered. I also assumed that the heat generated by producers such as plants was negligible to that produced by consumers (compare the thermal signature of a person to that of a tree). Though if someone can show me some autotrophs that generate tons of heat, I would appreciate the info. It is interesting to see how the overall balance is energy from the sun and mass from the environment equals waste mass and energy dissipated as heat (in large part). However, the intermediate steps become quite complicated and modeling them would take some mathematical juggling, the result of which could describe the mass and energy distribution in a particular biosphere.
It should be noted that I used a more in depth model to describe the consumers than the autotrophs and decomposers, due to the greater complexity of these organisms. The models themselves greatly simplify the biological processes that account for the mass and energy transfers from organism to organism.