Scientific documentation of crop land changes in the Sahel: A half empty box of knowledge to support policy?

•The Sahel is characterized by rapidly growing pressure on land.•Solid documentation of contemporary crop land changes is scarce.•Trends in crop land change in the Sahel depend on local contexts.•An inspection of existing knowledge leads us to caution against simple narratives.

The Sahel has been subject of considerable environmental research and development efforts, specifically since the droughts of the 1970s and 1980s. This article uses a meta-study approach to summarize knowledge of crop land change, the documented driving forces, and the perceived impacts. The analysis of case studies shows that crop land has increased in the majority of cases mainly due to population increase. However, despite population increase, crop land has been stable in some areas, particularly where land availability is a limiting factor or where farmers are able to intensify their farmers from expanding their plots or because households have diversified their activities. The study shows the huge gap in the scientific literature concerning actual measurements of crop land change in the Sahel, which is in contrast to the attention given to crop land changes in theoretical and policy discourses. On the basis of the poor documentation available on crop land change and the contrasting results observed, we point out the need to exercise caution with regard to simple narratives about crop land change.