Biodiversity and Preventing Land Degradation by CBD Braulio Ferreira de Souza Dias, Convention on Biological Diversity
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hile all life requires water, almost half of the world’s terrain, which is home to almost one-third of the world’s people, comprises areas where water scarcity is the norm. The arid, semiarid and subhumid lands, including deserts, grasslands, savannahs and Mediterranean ecosystems, cover about 41 percent of the world’s land and are home to around 2 billion people, or 30 percent of the global population, and provide approximately 44 percent of the world’s cultivated systems. These carefully balanced ecosystems are at the heart of the challenges we all face in the 21st century. Conserving them, protecting their biodiversity, preventing land degradation, and mitigating effects of drought will all be important if we are to feed a growing population, adapt to climate change, guarantee water security, and ensure secure livelihoods for billions of the world’s poorest people. The solutions to conserving these lands and preventing their degradation lie in biodiversity—the variety of life and the patterns and relationships it forms. Because of the harsh conditions in dry and subhumid lands, many species have developed unique adaptations. The gemsbok (large antelope) of the Kalahari Desert, for example, can survive for weeks without drinking water, while the sociable weaver of southern Africa builds communal nests that can weigh up to 1,000 kg to ensure insulation from extreme temperatures.
However, through a combination of human and climatic factors, pressure is increasing on dry and subhumid ecosystems and the benefits they provide, such as food, forage, fuel, building materials, and water for humans and livestock. Droughts, especially when associated with desertification, can have serious impacts on biodiversity, putting further stress on ecosystem resilience. But there is inspiring work being carried out to conserve the biodiversity that underpins these provisioning services. This work includes past winners and semifinalists of the United Nations Convention to Combat Desertification Land for Life Award. For instance, sixty years ago, in the arid lands of Inner Mongolia in China, one-third of the land was desert, forest cover was only 5 percent, and droughts were frequent. Through scientific policy planning and mass mobilization, the government of Chifeng rehabilitated 750,000 hectares of degraded land. Each hectare of shelterbelt forest prevents, on average, 10 tons of soil loss each year. In 2012, the forest cover of Inner Mongolia had risen to 20 percent. Government and residents worked together, signing “responsibility contracts,” making the job of combating desertification a priority across all levels of government and ensured its integration into local development planning.
L and for Life . BIOLOGICAL DIVERSIT Y
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