Avant-propos La notion de désertification se définit comme une dégradation des sols en zone aride, semi-aride et subhumide sèche, souvent appelée simplement « zone aride ». On estime qu’elle résulte d’une combinaison de facteurs, parmi lesquels les changements climatiques et l’activité humaine. Plus d’un tiers de la superficie totale de la terre est considéré comme zone aride. En termes démographiques, c’est un cinquième de la population totale du globe qui vit en zone aride déjà dégradée ou menacée de désertification.
Desertification is defined as land degradation in arid, semi-arid and dry sub-humid areas, resulting from various factors, including climatic variations and human activities. More than one third of the surface of the earth consists of drylands. In terms of population, one out of every five people of the world live in already degraded or desertification-prone drylands. These people include many of the world’s poorest, most marginalized, and politically weak citizens. For instance, nearly 325 million people in the African continent live in drylands.
Comme la Préface l’a souhaité, ce document est conçu comme un plaidoyer. Son objectif, en effet, est de montrer pourquoi il faut aujourd’hui replacer la Convention de Lutte contre la Désertification au cœur des stratégies engagées pour affronter la crise montante de l’écosystème global. Son point de départ est un constat sans appel : la progression de la désertification et de la dégradation des terres et des eaux conduisent inéluctablement à un développement non durable (Chapitre I).
The drylands of Africa, exclusive of hyper-arid zones, occupy about 43 per cent of the continent, and are home to a rapidly growing population that currently stands at about 325 million people. Dry zones, inclusive of hyper-arid lands, cover over 70 per cent of the continent’s terrestrial surface. Outside of the cities many dryland inhabitants are either pastoralists, sedentary or nomadic, or agro-pastoralists, combining livestock-rearing and crop production where conditions allow.
Land use practices contribute to both the emission and sequestration of greenhouse gases. Land is where the struggle to adapt to climate change will be won or lost by the poorest of the poor. Land science is a priority area of collaboration between UNCCD and UNFCCC, if land-climate insights and actions are to be optimized. It can also foster the synergies continually called for by Parties to the three sister Rio Conventions.
Drylands have the potential to play a big role in climate mitigation and, in doing so, to deliver significant co-benefits
The Kyoto Protocol negotiated in the mid-1990s to address climate change adaptation and mitigation will expire in 2012. This protocol represents one of the two milestones that the multilateral negotiation of climate change has delivered. Ten years after its adoption, the climate change negotiators decided upon the second largest milestone when they approved the Bali Action Plan at their 2007 meeting in Bali.
Human activities have resulted in unprecedented phenomena and severe impacts for the 21st century such as land degradation, natural resources scarcity, climate change, and a rapid decline in biodiversity. These alterations engender secondary effects such as political conflicts, disputes over resources, social disruptions and sudden shocks of catastrophic weather events which are becoming more frequent in critical regions of the world, particularly in drylands; and exacerbate threats for human, national and international security.
Often, when people think of drylands, they think of deserts and hostile living conditions, economic hardship and water scarcity. But that is not what drylands are all about. If managed well, drylands are often fertile and capable of supporting the habitats, crops and livestock that sustain the entire global population.