Even as people gasp for air in Moscow, Russia's authorities have begun to cut down the forests that surround the city, ostensibly to make space for a badly needed road from Moscow to St Petersburg.

ECONOMIST: A potent mix of heat, haze, alcohol and corruption

To reduce the risk of ambushes and fake checkpoints, the army has cut down ancient eucalyptus forests to their stumps, and burnt undergrowth to a cinder.

ECONOMIST: Algeria

"Coca production was not going to be reduced just because fumigation flights spray some fields, as long as these farmers don't have any other economic options, except to cut down forests to grow coca somewhere else, " said Adam Isacson of the Washington-based Center for International Policy.

BBC: NEWS | Americas | Coca-growing spreads in Colombia