Root interactions and evaluation of agroforestry and intercropping systems in Benin, West Africa

About the book In West Africa, traditional smallholder fallow systems urgently need sustainable intensification while maintaining soil fertility. Agroforestry systems were propagated to attain these targets. Earlier work, however, had not shown the expected positive effects on yield of the interplanted staple crops due to shading as well as root competition for nutrients and water. From 1995 until 1999, within the frame of the special research programme 308 (1985-1999) “Adapted farming in West Africa” of the University of Hohenheim, root studies were carried out in Southern Benin using the profile wall method for direct root observation and destructive soil monolith sampling. To estimate sustainability of the various treatments, i. e. fertilised, annual and perennial alley cropping in comparison to local practice, and production systems, i. e. maize-cassava intercropping, cassava sole-cropping as well as alley vs. block arrangement of perennial leguminous trees, yield trends were calculated for the three central trial sites at different edapho-climatical ecozones. Additionally, to quantify the complex interactions in agroforestry as well as in intercropping systems, data were used in system process modelling to give quantification of sustainable land management.