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84. Fire
2013-09-06
In African savannahs, or grasslands, wildfires are common. When wildfires spread uncontrolled, the heat and flames can cause damage on several levels.
Nearly all of the fires in the savannahs are caused by humans. Nature plays a very small role.
With climate change, there’s concern the savannahs will become even more dry, making destructive wildfires much more likely.
That’s why scientists at the World Agroforestry Center and their partners developed a system to intentionally set fires. It’s known as early burning. It consumes layers of biomass before they build-up to highly burning levels. Efforts to prevent fires altogether can actually make things worse.
So an early burn needs to be done when the conditions are just right – not too wet or not too dry. Fires intentionally set at that time not only consume the biomass, but prevent dangerous fires later in the season.
The early burns are generally fast moving and stay mainly on the surface. They cause only minor damage to trees, soil nutrients or microorganisms.
