A single metric can now pinpoint where saving a forest matters most.

Global conservation goals require knowing where protecting or fixing land does the most good. People often pick areas simply because the habitat is currently healthy, cheap, or large. However, these factors do not show which spots cause the biggest landscape-scale impacts if damaged or repaired. To solve this, researchers built a method that tests how sensitive an entire network of connected habitat is to local changes. By combining this sensitivity with an area's current condition, they mapped two things: places with high loss potential, where damage ruins the wider network, and places with high gain potential, where fixing the land creates massive network benefits. Testing this on forest data in Norway, they found that gain potential is not just in the most degraded forests. Crucially, existing protected areas poorly cover both types of critical land, though they cover loss potential better than gain potential.

Why it matters

Governments have pledged to conserve and restore huge areas of land, but they have limited money and time. This work gives them a way to find the exact spots where protecting a forest from logging, or letting it regrow, will have the biggest effect on the whole landscape. It separates places where damage would be catastrophic from places where restoration would be most valuable, so limited resources go where they do the most good.

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