Land use and land cover

Concerning its natural vegetation, the upper Mefou sub‐catchment is located in a transition zone between the dense humid forest of the bimodal precipitation regime and the zone of lesser forests. So there tend to be single huge trees with a more dense coverage of smaller trees and shrubs. The mountainous areas in the north‐west and east of the catchment have relatively dense vegetation coverage, except of some rocky outcrops, while the south‐east is peri‐urban and only the wetlands are covered by natural vegetation.

In accordance to the two rainfall seasons, there are two growing seasons, one from mid‐February to June and one from September to mid‐November, where the first is most important for agriculture. Planting starts at the beginning of the rainy season. Sometimes maize is sown earlier and cassava is planted when other crops are already growing. Preparation of the fields starts one month before the planting, and includes cutting trees and bush when the field is used the first time, or clearing the fallow. After the field is burned, tillage is done by simple hand‐held hoes. There are two types of tillage: with and without ridges. Maintenances of the fields – weed removing – takes place once or twice a growing season. Some crops are harvested after the rainy season, while cassava will be harvested after a second rainy season.

The farming system might be classified as shifting cultivation. So, a short period of growing (one or two years) will be followed by a long period of fallowing (up to 15 years). In areas with a higher population density, the period of the fallow is shorter.

One main feature of the farming system is intercropping, also known as mosaic or mixed cultivation. Up to four crops may be planted in one field. The major crop associations are: maize or cassava combined with groundnuts, beans or sweet potatoes. Makabo or yams are also associated, but may also occur as more or less single plants. Plantain is a major food tree found on fields. Sometimes single palms are used for the production of palm wine (vin blanc).

Besides this ways of subsistence farming, the surplus in the production is often sold on the market of Mokolo in Yaoundé. The main cash crops are cacao and palm oil. The plantains meanwhile cover only a small area of the catchment and are owned by local farmers.