Wednesday April 27, 2022
Eos —
Rivers are fragmented by large and small dams the world over, be it for power generation, water supply, or flood control. Direct impacts of such fragmentation include barriers to sediment and nutrient flow and isolation of fish populations. To better quantify river fragmentation, researchers have designed a novel index, the catchment area-based fragmentation index (CAFI), as described in a paper published last month.
In contrast to current methodologies that determine river fragmentation on the basis of river length, CAFI and its derivative, the rainfall-based fragmentation index (CARFI), use catchment area as an indicator of the extent of river habitat.
Suman Jumani, a freshwater ecologist at the University of Florida and lead author of the new study, said that catchment area is a good predictor of the volume of water flowing in a stream. Additionally, she added, a catchment is relatively easy to quantify, so it “works well as a proxy for in-stream habitat availability.”