Non-native plants clog Japanese river
Part of the Kyu-yoshino river in Kagoshima Prefecture has turned green:
The surface of the river is covered in water lettuce plants. Water lettuce is not native to Japan, and it is illegal to cultivate it here, but somehow a few plants managed to find their way into the river and multiply. It is feared that the plants are suffocating the river and killing local plants and fish, so authorities are making their best efforts to remove all the water lettuce. They expect the clean-up to cost hundreds of millions of yen.
