Desertification

7. Is there a link between desertification, global climate change, and biodiversity loss?

Biological diversity, which contributes to many of the services provided to humans by dryland ecosystems, is diminished by desertification. Vegetation and its diversity are instrumental in soil conservation and in the regulation of surface water and local climate. The disruption of the interlinked services that are provided by dryland plant biodiversity is a key trigger for desertification and its various consequences, including the loss of habitats for other species.

Fig 6.1 Linkages between Desertification, Global Climate Change, and Biodiversity Loss

Desertification affects global climate change through soil and vegetation losses. Indeed, dryland soils contain a lot of carbon which could be released into the atmosphere as a result of desertification, with significant consequences for the global climate system. It is estimated that each year 300 million tons of carbon are lost to the atmosphere from drylands as a result of desertification. This represents about 4% of global emissions from all sources combined.

The effect of global climate change on desertification is complex and not yet sufficiently understood. On the one hand, higher temperatures can have a negative impact through increased loss of water from soil and reduced rainfall in drylands. On the other hand, an increase in carbon dioxide in the atmosphere can boost plant growth for certain species. Although climate change may increase aridity and desertification risk in many areas, the consequent effects of biodiversity loss on desertification are difficult to predict.

Environmental management approaches for combating desertification, conserving biodiversity, and mitigating climate change are linked in many ways, thus a joint implementation of the U.N. Conventions that target Desertification, Biological Diversity, and Climate Change can yield multiple benefits. More...