Tuesday, February 1, 2011
That's essentially what the Mother Nature Network asks in its article Was Genghis Khan History's Greenest Conqueror? The article reports on the latest research led by Julia Pongratz from the Carneige Institution's Department of Global Ecology:
Over the course of the century and a half run of the Mongol Empire, about 22 percent of the world's total land area had been conquered and an estimated 40 million people were slaughtered by the horse-driven, bow-wielding hordes. Depopulation over such a large swathe of land meant that countless numbers of cultivated fields eventually returned to forests.
In other words, one effect of Genghis Khan's unrelenting invasion was widespread reforestation, and the re-growth of those forests meant that more carbon could be absorbed from the atmosphere.
But thankfully it may not be necessary kill mass numbers of people to save the planet. In fact, it seems pretty clear that looking strictly at forestation, the U.S. has far more forested acreage than it did a century ago, while adding vast population increases. Pongratz says the larger lesson is that we should learn from history to inform the present and future of land use, which I agree with completely:
"Based on the knowledge we have gained from the past, we are now in a position to make land-use decisions that will diminish our impact on climate and the carbon cycle. We cannot ignore the knowledge we have gained," she said.