Answer:
A waterwheel in a river or hydraulic wheel, refers to the device which circular form that transforms the water flow into other useful form of energy. It was built in ancient times to agricultural activities purposes, which made people able to take advantage of the strength of the river current.
This waterwheel concept could be used as an analogy for the movement of the flow of energy and matter in the ecosystem, both energy movements are circular, that is, cyclic. The waterwheel uses the conservation of energy theorem, which expresses that the energy is a constant that it gets transformed to different ways, this concept is presents in the waterwheel and the energy and matter flow in the ecosystem. So, this couls be an accurate comparison between them, there are cyclic energy transformations.
On the other hand, an inaccurate comparison between them could be in the literal scenario, that is, the process invoved in the energy and matter flow in the ecosystem are not present in a waterwheel process, which of them have different processes that performs a cyclic energy transformation.