Reuters: China’s dramatic economic slowdown is paying an environmental dividend, slashing emissions levels from the world’s biggest greenhouse gas emitter as its highest-carbon industries begin to contract. The question Beijing will soon face is how it will manage to sustain those curbs once growth is restored. Some say it’s moving in the right direction; others are far less certain, as the government, facing a threat to the economic miracle on which its credibility was built, rushes to pump …