This paper follows the transition from ethnobotany to a deeper scientific understanding of the food and medicinal properties of African agroforestry tree products as inputs into the start of domestication activities. It progresses on to the integration of these indigenous trees as new crops within diversified farming systems for multiple social, economic and environmental benefits. From its advent in the 1990s, the domestication of indigenous food and non-food tree species has become a global programme with a strong African focus. This review of progress in the third decade is restricted to progress in Africa, where multi-disciplinary research on over 59 species has been reported in 759 research papers in 318 science publications by scientists from over 833 research teams in 70 countries around the world (532 in Africa). The review spans 23 research topics presenting the recent research literature for tree species of high priority across the continent, as well as that in each of the four main ecological regions: the humid zone of West and Central Africa; the Sahel and North Africa; the East African highlands and drylands; and the woody savannas of Southern Africa. The main areas of growth have been the nutritional/medicinal value of non-timber forest products; the evaluation of the state of natural resources and their importance to local people; and the characterization of useful traits. However, the testing of putative cultivars; the implementation of participatory principles; the protection of traditional knowledge and intellectual property rights; and the selection of elite trees and ideotypes remain under-researched. To the probable detriment of the upscaling and impact in tropical agriculture, there has been, at the international level, a move away from decentralized, community-based tree domestication towards a laboratory-based, centralized approach. However, the rapid uptake of research by university departments and national agricultural research centres in Africa indicates a recognition of the importance of the indigenous crops for both the livelihoods of rural communities and the revitalization and enhanced outputs from agriculture in Africa, especially in West Africa. Thus, on a continental scale, there has been an uptake of research with policy relevance for the integration of indigenous trees in agroecosystems and their importance for the attainment of the UN Sustainable Development Goals. To progress this in the fourth decade, there will need to be a dedicated Centre in Africa to test and develop cultivars of indigenous crops. Finally, this review underpins a holistic approach to mitigating climate change, as well as other big global issues such as hunger, poverty and loss of wildlife habitat by reaping the benefits, or ‘profits’, from investment in the five forms of Capital, described as ‘land maxing’. However, policy and decision makers are not yet recognizing the potential for holistic and transformational adoption of these new indigenous food crop opportunities for African agriculture. Is ‘political will’ the missing sixth capital for sustainable development?

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Mangroves (stretch of intertidal tropical and subtropical forests between inland coastal forests and the sea) are being exploited at a rate that is unprecedented, there is loss of biodiversity because of conflicting and unsuitable uses. This study was aimed at promoting the protection of mangrove and associated coastal forests within Tiko and Limbe III municipalities in south western Cameroon, Central Africa via the contribution of buffer zone agroforestry. Representative traditionally dominant agricultural land use sites were surveyed for the identification and analysis of farming practices using participatory rapid appraisal (PRA). Data collected (qualitative and quantitative) were subjected to descriptive and inferential statistics. Out of twelve (12) agroforestry practices currently carried out by farmers under three widely dominant classic agroforestry systems (agri-silvicultural – plantation and non-plantation, silvo-pastoral and agri-silvo-pastoral systems), 5 of them under plantation and non-plantation systems (palms on crops lands, cocoa-based, rubber on crop lands, scattered trees on farmland and home gardens) were considered climate smart agroforestry practices. The maximum diameter, density, height and crown diameter of trees were dominant in the cocoa-based except for the mango-based which had the maximum tree height. The tree size class for poles (≥10cm to <30cm) was dominant in the 5 practices. For a more inclusive green economy and climate smart agriculture, some improvements on tree density, shade management and choice of multi-purpose trees species (Cedrela sepium, Moringa oleifera, Leucaena leucocephala and fruit trees) for vital functions such as firewood, soil improvement, medicine, food and construction are advocated to enhance sustainable exploitation of adjacent coastal forests thus protecting mangrove. Moreover, on account of resultant stable tree species, structural and use diversity of adjacent coastal forests, further make buffer agroforestry to hold promise for the conservation of fragile and vulnerable mangroves. There is therefore also need to expand the present study in other mangrove areas especially the mangroves of Cameroon Estuary which is the major deforestation hotspot in Cameroon.

Land cover change is a growing concern around the world. This is especially true for protected areas which are rapidly degrading owing to pressure from anthropogenic activities. The aim of this study was to analyze land cover change for the periods 1980, 2008 and 2020 and its implication on the environment in and around the Dja Biosphere Reserve in south eastern Cameroon. This was done using remote sensing and geographical information systems techniques to quantify and measure the extent of land cover change in the study area for forty years. Household surveys were equally undertaken through the administration of questionnaires to farmers in villages located within the Dja Biosphere Reserve. Collected data was analyzed through the use of GIS software as well as Microsoft Excel. From the land cover maps, four classes were found: dense forest, cultivated areas, water surface, and buildings and bare soils. The transition matrix between 1980 and 2008 showed that 6477.81 ha of dense forest was lost to cultivated areas and between 2008 and 2020, 722.84 ha of dense forest was lost. Between 1980 and 2008 cultivated areas lost 0.07% and gain 0.72% between 2008 and 2020. Building and bare soils increase by 0.28% between 1980 and 2020. The Kappa index of agreement was 0.91 % between 1980 and 2008 and 0.88% between 2008 and 2020. Slash and burn agriculture (43.3%), hunting (36.3%) and harvesting of tree-based products (20.3%) were identified by farmers as the human activities with the most negative impact on the reserve. Results revealed that, there are still opportunities to safe this vulnerable reserve from the negative effects of land cover change through the practice of agroforestry.