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The tropical glaciers are just vanishing. The effects can be seen in many of the mountain ranges, such as Andes, Himalayas and Kilimanjaro in Africa. Now it needs to be seen how the extinction of these glaciers are going to affect the fresh water flows in these regions. Already evidence has come to support the claim that many of the rivers are witnessing a decrease in their volumes.
I'm not quite following that. If a glacier shrinks, in the short run that increases ground water, which should cause a rise in rivers. In the longer run, is there a decrease in river volume?
The hydrologic cycle describes how water evaporates, then is deposited as rain or snow, then moves downhill to streams and rivers and eventually to oceans then to evaporate again.
Generally, the only way for a decrease in river volume to occur would seem to be for an area to have lower humidity in the air.
Sure, there could be some localized areas basically to the sides of glaciers that would have water flow affected by the shrinking (or expanding) of a glacier. So what?