Large tropical mountain river systems aren’t getting the respect they deserve – at least not when it comes to research and conservation.
It’s a head-scratcher considering how important they are. Without these river systems, the Amazon wouldn’t be The Amazon. Dar es Salaam likely wouldn’t be Tanzania’s most populous city. The Western Ghats in India wouldn’t be the world’s most densely populated biodiversity hotspot.
“The way people say tropical rainforests are super important to the planet, tropical montane rivers are also critical ecosystems and deserve more attention globally,” said Elizabeth Anderson, an FIU assistant professor in the department of Earth and Environment and researcher in the Institute of Water and Environment who co-authored a study in Science calling attention to this oversight.
The reality, Anderson said, is these river systems are responsible for so much globally. Lowland rainforests like the Amazon are centers of biodiversity and carbon storage. These river systems move massive quantities of water, nutrients and sediments, which sustain these forests, their biodiversity, and the people that depend on them. Ignoring tropical mountain river systems is like ignoring the hands that feed many tropical rainforests.
If researchers study the entire river system – not just headwater springs that often supply water to human populations or lowland rivers that meander through tropical forests – they would discover the large distance in between headwaters and lowlands is vital.
“It’s where the magic happens,” Anderson said.
In many cases, hydropower dams are interrupting the flow of water, sediments and fish along these river systems. Rivers are being polluted or are being used unsustainably for industry and agriculture. Further research could focus on factors responsible for driving change there, but also on opportunities for conservation including following the lead of Costa Rica and Colombia in affording tropical rivers special protected status.
“There are a lot of open frontiers here,” said Guido Herrera-Rodriguez, an FIU researcher who also co-authored the paper. “These rivers serve as sentinels of global change. They are part of a connected system that influences other rivers and the oceans.”