Improved forest resource management for combating desertification in Sudano-Sahelian Africa

Agroforestry systems as traditionally practiced on sandy soils west of the White Nile (where the gum acacia occurs naturally) were compared with newly introduced practices in the clay plain surrounding the Blue Nile. In Sudan, there is a trend to increase the area of gum gardens because of the economic and potential environmental benefits involved, but agroforestry management has not been sufficiently researched in the new global and national context.

Farmers’ perceptions related to trees and forestry, as well as participatory planning methodologies were also studied in Gedaref State in the Blue Nile region where the government is introducing and testing new community-based natural resource management models. Long practised sandy-soil agroforestry and gum production had earlier yielded an extensive database on factors controlling the yields of gum and associated field crops, but there existed no previous comprehensive scientific analysis of the situation.

Another line of research included comparisons of early performance among different acacia seed sources, so as to clarify the genetic variation and provide new, higher-yielding acacia genotypes for cultivation on different types of soils. Furthermore, at two selected sites, an environmental-economic analysis was carried out on the alien, potentially invasive tree species Prosopis juliflora, particularly comparing its impact on farmlands on sandy and clay soils. Additional separate financing also allowed two more studies, on women as natural resource managers, and on improvement of date palm management using biotechnology tools.