Agroforestry has been widely practiced in the Loess Plateau region of China because of its prominent effects in reducing soil and water losses, improving land-use efficiency and increasing economic returns. However, the agroforestry practices may lead to competition between crops and trees for underground soil moisture and nutrients, and the trees on the canopy layer may also lead to shortage o...

Building on farmer’s agroecological knowledge to design environmental-friendly agricultural systems is crucial given the environmental impact of industrial agriculture. We investigated the drivers of farmers’ knowledge of agrobiodiversity management and analyzed how farmers’ knowledge and their current farming contexts may guide future farming systems in sub-humid (Bassila) and semi-arid (Bouko...

Jatropha curcas L. (Euphorbiaceae) is a small tree with valuable attributes, including that as a commercially important non-edible oilseed that grows naturally in the equatorial Americas and has spread to other tropical countries. J. curcas has been found to be the most suitable tree species for production of biodiesel as it can be grown as a quick yielding plant even in problem soils and adver...

The snowshoe hare (Lepus americanus). several species of voles (Microtus spp.), the northern pocket gopher (Thomomys talpoidest. and the red squirrel (Tamiasciurus hudsonicus) cause serious damage to forest plantations and stands (and voles and pocket gophers in tree fruit orchards) by their feeding activities. Certain synthetic predator odors are reviewed which have produced significant avoida...

The high prevalence of food insecurity experienced by northern First Nations partially results from dependence on an expensive import-based food system that typically lacks nutritional quality and further displaces traditional food systems. In the present study, the feasibility of import substitution by Agroforestry Community Gardens (AFCGs) as socio-ecologically and culturally sustainable mean...

Citrus is the main fruit tree crop in the world and therefore has a tremendous economical, social and cultural impact in our society. In recent years, our knowledge on plant reproductive biology has increased considerably mostly because of the work developed in model plants. However, the information generated in these species cannot always be applied to citrus, predominantly because citrus is a...

This thesis consists of a summary and four self-contained papers. Paper [I] examines whether the implementation of a social safety net programme in Ethiopia has affected the value, risk and composition of farmers‟ crop portfolios. The empirical analysis suggests that the value and risk of the crop portfolio have not been altered due to the programme. However, the programme seems to have brought...

The effects of regulated deficit irrigation (RDI) were studied on 9 year-old apricot-trees (Prunus armeniaca L. cv. ‘Búlida’) grafted on ‘Real Fino’ rootstock. Two irrigation treatments were established. The first, a control treatment, was irrigated to fully satisfy the crop water requirements (100% ETc) and the second, a RDI treatment, was subject to water shortage during the non-critical peri...