Answer
Yes, since ecosystems depend on how they are defined. You could have multiple ecosystems, or subecosystems, in one physical place with few or no interactions between them. For example, a bog in the middle of a temperate rainforest includes very different species from those in the forest and those species would interact little with those in the forest.
Work Step by Step
The key here is to see how ecosystems can be defined by scale, so that two may coexist side-by-side in one physical place, with little interaction between them. They might still be combined to define a larger ecosystem in which they still did not interact much.
