What would non-ecumene mean

Non-ecumene means regions of the world that are uninhabited or very sparsely populated. Usually the regions of the world that are ecumenic and non-ecumenic are hard to draw as many regions which are densely populated merge with sparsely populated regions and the boundaries that they do share are not static, as they can change with time and movement of people.

South wales composes a lot of coal in that region.