La désertification est un phénomène mondial qui affecte près de la moitié de la surface de la planète, notamment en Afrique où 43 % des terres se trouvent dans des zones arides ou semi-arides. La lutte contre la désertification dans ces milieux constitue une des priorités majeures des États sahélo-sahariens du Circum-Sahara. L’ « Initiative africaine Grande Muraille Verte » (IAGMV) répond à ces enjeux via un ensemble d’actions destinées à assurer le développement socio-économique régional. Elle signe l’émergence d’un leadership de l’Afrique dans la prise en charge de ses défis environnementaux, à travers la gestion durable et la valorisation de l’important potentiel de développement des zones arides du continent. Malgré l’acquisition de connaissances scientifiques et techniques dans les domaines liés à la gestion durable des terres en zones arides, la majeure partie de ces données n’ont pas été capitalisées et diffusées, ce qui fragilise la mise en place des différentes politiques de lutte contre la désertification. Cet ouvrage a ainsi pour objectif de faire l’état des lieux des connaissances et initiatives sur la gestion des problématiques de la désertification. Il capitalise les résultats, les expériences, les techniques et autres données issues de la recherche scientifique, mais aussi des pratiques et des savoirs traditionnels acquis au cours des cinquante dernières années. Il propose les recommandations qui en découlent afin d’optimiser les stratégies et les performances des programmes et projets de l’ « Initiative Grande Muraille Verte ». Il s’adresse aux chercheurs, hydrologues, écologues, agronomes ainsi qu’aux développeurs et aménageurs investis dans les programmes de lutte contre la désertification.

This edition of Nature & Faune journal explores the science and innovations (technical, social and policy) that can support the achievement of the African dream of restoring 100 million hectares of its degraded land. Articles in this edition share experiences on challenges, opportunities and successful restoration, including farmer managed natural regeneration, improved management of smallholder woodlots, reforestation, evergreen agriculture with intercropped trees, and associated sustainable land management practices such as water harvesting and erosion control. Africa’s Great Green Wall is presented in this edition as a transformative model for rural communities’ sustainable development. In particular the lessons learned from the “Action Against Desertification” programme funded by the European Union and implemented by FAO with partner countries and organizations, are discussed, paving a way towards the implementation of African Forest Landscape Restoration Initiative. Initiatives to address land degradation and desertification trends in Africa, promote sustainable land management, and restoration of degraded forests and landscapes include Africa’s Great Green Wall initiative, and 2016’s African Forest Landscape Restoration Initiative – AFR100. Most of the articles dwelt on how efforts to this end are being pursued.

This book has been published by Allenvi (French National Alliance for Environmental Research) to coincide with the 22nd Conference of Parties to the United Nations Framework Convention on Climate Change (COP22) in Marrakesh. It is the outcome of work by academic researchers on both sides of the Mediterranean and provides a remarkable scientific review of the mechanisms of climate change and its impacts on the environment, the economy, health and Mediterranean societies. It will also be valuable in developing responses that draw on “scientific evidence” to address the issues of adaptation, resource conservation, solutions and risk prevention. Reflecting the full complexity of the Mediterranean environment, the book is a major scientific contribution to the climate issue, where various scientific considerations converge to break down the boundaries between disciplines.

The “Action Against Desertification in support of the implementation of the Great Green Wall for the Sahara and the Sahel Initiative, the UNCCD action plans in Fiji and Haiti, and South–South Cooperation in the African, Caribbean and Pacific Group of States” project (AAD) worked with eight countries in Africa, the Caribbean and Asia to tackle the detrimental social, economic and environmental impacts of land degradation and desertification (2014 to 2020). It was implemented by the Food and Agriculture Organization of the United Nations (FAO) and partners, with majority of funding from the European Union and co-funding from diverse partners. The project contributed to improving the conditions and productivity of agrosilvipastoral landscapes and the capacity to plan land restoration and manage forest and land resources. Livelihood improvements and concrete positive incidence on household income, food security, crops and milk production, and community interactions. It increased awareness and support policy makers developing intervention strategies that address D/LDD. The large-scale, heavy machinery-based technical intervention logic was found appropriate to address desertification/land degradation and drought (D/LDD) in specific conditions and countries. The geospatial study estimated the contribution of Action Against Desertification (AAD) to carbon sequestration to be between 384 000 and 1.27 million tonnes of carbon sequestered. The evaluation recommendations include further investments in training; building awareness and addressing climate change and land degradation; increasing political and policy coherence; guaranteeing sustainability and buy-in from beneficiaries; building in sustainable financing mechanisms at all stakeholder levels; increasing opportunities; and developing non-timber forest product (NTFP) value chains to create and develop viable markets for the products.