Murky waters

摘要

FORAGING in the swamps of Lake Victoria in East Africa, this man makes a living by selling old plastic bags to recyclers. Wetland areas usually purify the water in the lake and run-off by filtering it. However, a growing amount of pollution is disrupting this process. For instance, blue dye from these plastic bags will eventually seep into the water. This isn't the only problem besetting Lake Victoria, which is more than 300 kilometres wide and the largest by area in Africa. Climate change is causing it to steadily dry up, while cities in the bordering nations of Kenya, Tanzania and Uganda are dumping untreated waste into its waters. One million tonnes of fish are harvested from the lake each year. The pressure on its stocks is being made worse due to poaching and overfishing.