In the oasis of the Mauritanian Sahara, the main refuge for date palms, climate change is tightening its grip. These ecosystems, which depend on shallow groundwater reserves, are at risk because recent rainfall has not been enough to replenish them. This poses a major threat to farmers in a country where less than 0.5 percent of the land is arable, jeopardising the livelihood of tens of thousands of people who have depended on oasis crops for centuries. FRANCE 24's Simon Martin, Sarah Sakho and Caitlin Kelly report.