The United Nations says almost a quarter of the earth's surface and over a billion people are affected by desertification. In Africa alone 325 million people are said to be living "precariously" in arid zones. Jean Ziegler, UN special rapporteur on the right to food, says not enough is being done to protect the estimated 250 million victims of ecological destruction worldwide and the millions of environmental refugees being forced off the land and into slums. "These refugees have no protection under international law," he said.