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.

The book brings together a series of contributions with a common goal of reflecting the links between economic development and rural development. The scenario is dotted not only with old and new wounds but also with innovative strategies in an attempt to overcome existing delays. The chapters of the book are composed of scenarios full of case studies. The plans to be adopted to help the countries that have lagged behind fueled an intense debate since the obstacles to development, as evidenced by the extensive scientific literature available, now appeared to be the realities present in the socio-economic structures of a large number of villages. Although the data available are still few, it is assumed that the Covid-19 pandemic will make a landscape already full of criticalities even more fragile.

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.

Notre zone d'etude localisee dans la region de Matam est soumise au climat sahelien avec une vegetation de type arbustive, adaptee a la forte chaleur et au stress hydrique, avec une pluviometrie moyenne annuelle de 350mm/an. La communaute rurale de Loughere Thioly, sylvo-pastorale, est partie integrante du Ferlo. C'est un milieu quasi inaccessible surtout en saison des pluies, d'ou l'appellation ironique une terre abandonnee des dieux . C'est une zone en degradation avancee. Cette degradation du couvert vegetal entraine l'alteration toute entiere du milieu vivant. Il en resulte logiquement que si l'on conserve la vegetation, on conserve a la fois le sol, la faune et la vie humaine. La Grande Muraille Verte bien implantee dans cette zone s'est donnee pour mission de conserver, valoriser, restaurer le couvert vegetal afin de lutter contre l'avancee menacante du desert, manifestation clinique du changement climatique. Pays signataire du Protocole de Kyoto, le Senegal s'investit grandement dans la lutte pour l'attenuation et l'adaptation aux effets du changement climatique. Le pays s'ouvre par ailleurs au marche du carbone de par les nouveaux mecanismes de flexibilite comme le MDP."

The question in the title of this book draws attention to the shortcomings of a concept that has become a political tool of global importance even as the scientific basis for its use grows weaker. The concept of desertification, it can be argued, has ceased to be analytically useful and distorts our understanding of social-environmental systems and their resiliency, particularly in poor countries with variable rainfall and persistent poverty. For better policy and governance, we need to reconsider the scientific justification for international attempts to combat desertification. Our exploration of these issues begins in the Sahel of West Africa, where a series of severe droughts at the end of the 20th century led to the global institutionalization of the idea of desertification. It now seems incontrovertible that these droughts were not caused primarily by local land use mismanagement, effectively terminating a long-standing policy and scientific debate. There is now an opportunity to treat this episode as an object lesson in the relationship between science, the formation of public opinion and international policy-making. Looking beyond the Sahel, the chapters in this book provide case studies from around the world that examine the use and relevance of the desertification concept. Despite an increasingly sophisticated understanding of dryland environments and societies, the uses now being made of the desertification concept in parts of Asia exhibit many of the shortcomings of earlier work done in Africa. It took scientists more than three decades to transform a perceived desertification crisis in the Sahel into a non-event. This book is an effort to critically examine that experience and accelerate the learning process in other parts of the world.

The focus of this book is on the key water-related vulnerabilities to climate change in Africa, particularly in its most vulnerable areas, exploring potential management responses to such vulnerabilities. The African countries are particularly exposed and vulnerable to the negative impacts of climate change, with important impacts on water resources and hydrological systems, water availability, water resource management and sea level variations. Already, under various anthropogenic pressures, the status of water resources in Africa has been changing over the past decades, with decreasing water quality, falling groundwater levels, and variability in rainfall, both in terms of timing and intensity. Climate change will further accelerate the rate of change, affecting the ability of people and societies to respond in a timely manner. It is clear that there is no quick fix to the pressures imposed on water resources by climate change. Increasing the resilience of ecosystems and communities to extreme events such as flooding and drought, and integrating climate change risks and opportunities into development decision-making is indeed a key challenge, as much a technical climate-change one, as a political and developmental challenge. The book, in this regard, intends to contribute to the debate around climate change in relation to water resources management in Africa, and in particular inform policy decisions and actions that will improve governments’ and communities’ ability to manage the challenges of climate change and variability in relation to the aquatic ecosystems that they depend on. The knowledge collected in this book will benefit policy makers, researchers, as well as other stakeholders.

Populations in the G5 Sahel countries are growing rapidly. Given these large cohorts of young populations, over the next five years 11.4 million youth will turn 16 years old, and most will then start to seek jobs in the region. Although the countries are urbanizing, meaning that future economic growth may be faster in industry and services than in agriculture, in the short and medium run the bulk of new jobs are likely to be created in the agriculture sector and its supply chains. For the five countries of the G5 Sahel – Burkina Faso, Chad, Mauritania, Mali and Niger – this study aims to address the following questions: i) What employment can be created for youth, as agriculture and the agrifood value chains become environmentally sustainable as part of a rural green transition?; and ii) What policies, programmes and investment are needed to create these jobs and ensure that young women and men can access them?