I originally published this post on 29 July, but then Dr Baudron pointed to two additional papers on Twitter, and then later to another one, so I’m re-upping, for the second time, with a sixth bullet point.
There’s a nice series of papers on the benefits of diverse landscapes in Ethiopia from Frédéric Baudron of CIMMYT and others.
Just in case this tweet disappears, or whatever, here are the links:
- Wheat yields and zinc content are higher closer to forests because of elevated organic matter in the soil.
- Diets are also more diverse nearer forests.
- Livestock (but not crop) productivity is higher nearer forests, and smallholder systems generally more sustainable.
- Bird diversity benefits from tree cover too, and that provides important ecosystem services to smallholders.
- Even limited reforestation in the surrounding landscape is associated with higher wheat yields in simulations, and you can potentially measure it from space.
- “More people, more trees.”
“More people, more trees”. The take home message from this excellent paper is ‘more people, more trees’. The authors claim that this: “is a reforestation pathway not previously described in the literature.”
This claim is wrong. They have missed an important paper: Mather and Needle (2000), which related forest trends to human population and crop yields: “Most of the countries in which [crop] yields have increased faster than population are characterized by forest expansion or stability”, whereas “Most countries with population growth in excess of [crop] yield increase have shrinking forests”. They call this the ‘forest transition’, indicating “that there is no permanent, rigid, or deterministic rule linking population and forest trends”. In effect, agricultural intensification can save forest.
We discussed this in detail in a long critique of the Convention on Biological Diversity (Wood and Lenné, 2005). The journal editor for this paper was Mather. He commented that he had never received a paper from Fyvie before (from a croft in rural Scotland).
Mather, A.S., Needle C.L., 2000. The relationship of population and forest trends. Geographical Journal 166, 2–13.
Wood, D., Lenné J. L. 2005. “Received Wisdom” in agricultural land use policy: 10 years on from Rio. Land Use Policy 22, 75–93.