Last week, I wrote a news story based on a paper in Geophysical Letters for SciDev.net. The bare bones of the story is that a modelling study of West African rainforests and adjacent cropland found a pattern in local rainfall - rainfall increased by 4 to 6 times over cropland when next to rainforests, and fell by half over the rainforest.
Of course, rainfall in these areas is also affected by other factors such as ocean storms. But the local effect is significant, and, as I wrote in the SciDev.net article, can benefit farmers.
However, there is also a conservation aspect to this story. What happens to the rainforest due to the fall in rainfall is not known, and we can only speculate. But speaking to Tim Baker, a geographer at Leeds University, it was clear that he was concerned that the conservation angle should not be overlooked.
One of the implications of the rainfall modelling study for farmers might be that they should deforest in a ‘patchwork’ or ‘fishbone’ way (read more about this in this Mongabay article). But Baker said: “There is so much deforestation in West Africa that the forest is already in many areas, such as Ghana, very fragmented.” FAO figures show that Africa has had the second highest rates of deforestation between 2000 and 2005. “So there is not a strong policy message to say that we should have corridors or a patchwork of deforestation rather than large patches,” Baker continued.
“People talk about tropical rainforests ‘creating rain’ and being important because they maintain these cycles. It’s true, but it’s not just a forest…it’s a source of firewood, biodiversity, carbon storage…” he added.