Rally for rivers is a movement to save rivers initiated by a NGO Isha foundation.
But the initiative comes with poor understanding of the science of Forest-Rain theory.
What is Rally for Rivers is about?
Draft document by the Isha Foundation on Rally for Rivers aims to rejuvenate Indian rivers largely by planting trees or orchards or plantations for at least 1 km on both banks of India’s rivers.
The premise seems to be that forests generate rain, and India’s river banks are barren leading to the drying up of rivers.
What is Forest-Rain theory actually states?
An enduring claim about forests that they are responsible for creating rain and promote deposition of rainfall from clouds but it is not supported by any substantial evidence at the local scale.
At meso-scale climate models have shown that some of intercepted water retained by forest canopies gets re-evaporated and return as increased rainfall but this is no net increase in rainfall.
The current forest hydrology research suggests that the assumption that more trees equals more water is based on incorrect understanding of the hydrological cycle in forest ecosystems and the forest ecosystem is in fact a major user of water.
Thus forests decrease surface flows and it affects run-off into rivers leading to reduced flows in rivers.
What are the issues with the initiative?
The draft ignores the real reason of drying up of rivers due to phenomenal rise in diversions, since the 1940s and 1950s.
The draft document undermines the role of thousands of diversion structures in reducing the flow across India’s rivers.
Despite the fact that the area under forests in India reduced, there is no evidence that the reduction in forests have caused a reduction in rainfall.
The initiative lacks river basin perspective and is silent on the stream order within river basin for undertaking this gigantic task.
Instead of river basins the draft focuses on forests, attaching artificial causality to the occurrence of rainfall on the planet.
