Because it is essential for our survival, we are aware of the importance of saving water and monitoring our daily consumption. But the general public remains much less aware of the need to conserve sand, the second most exploited resource after water, and yet it is also essential to combat climate change.
Fifty billion tons per year: that is the amount of sand that is used annually in the world. “With this amount of sand, it would be possible to build a wall 27 meters high and 27 meters thick that would encircle the Earth”, says a new report from the United Nations Environment Program (UNEP). But like water, sand is not an infinitely renewable resource.
Why is it important to keep it?
Sand is the second most exploited natural resource in the world. The granules are mainly used as raw material for making concrete, asphalt or glass, in construction and construction.
Desert sand proves to be less attractive because of the wind-polished grains, which are less thick. It is therefore mainly what is extracted from beaches and other coastal banks (lakes, estuaries, rivers) that is under threat. “Most of the world’s major rivers have lost between half and 95% of their natural reserves of sand and gravel to the oceans”regrets the report.
However, marine sand plays an essential geological role as it limits soil erosion. “Keeping sand on the coast could be the most economically efficient strategy for climate change adaptation due to the way sand protects against storms and marine flooding and the effects of sea level rise. Such services should be factored into the value placed on sand .”points out researcher Pascal Peduzzi, director of the Global Resource Information Database (GRID) network and lead author of the UN report.
Create “a circular sand economy”
Unlike water, there are few official rules to ensure rational use of sand. A real social and environmental problem, as this resource is subject to significant trade and illegal extraction, causing conflict and insecurity of the inhabitants in certain countries, as is the case in India or Morocco.
To combat “these sand mafia” and preserve the environment of coastal landscapes, the UN report proposes several solutions and lists specific measures. For example, establishing an international standard to regulate the use of sand, establishing a fixed price for sand based on: “its real social and environmental value”create a “circular sand economy” by encouraging reuse of this resource or prohibiting the extraction of sand from beaches and its use in open landfills.
“The main limitation to responsible sand extraction is not technical: it is a matter of awareness and governance”supports Pascal Peduzzi.
(ETX Daily Up)