People might not be able to move mountains, but they can hurt them. That's the message of "Mountain Watch," a report billed as the first global assessment of mountain ecosystems. It concludes that mountains--which cover 24% of the world's land surface--are fragile and are being threatened by farming, grazing, fires, mining, roads, wars, and climate change. The report was released last month at the Mountain Summit held in Bishkek, Kyrgyzstan, as part of the United Nations' International Year of the Mountain.

Snows of Kilimanjaro are melting (yellow line is 1962 boundary).
CREDIT: CHRISTIAN LAMBRECHTS/UNEP-DEWA
Mountains are hardest hit in Africa, where almost half of the hilly regions are being used for cropland or grazing (compared with 14% in North America). And two-thirds of the continent's mountainous areas have been afflicted by war or "high-intensity conflict." Climate change is also doing its bit. In the Himalayas, lakes brimming with glacial meltwater threaten to flood mountain villages.