India, Oct. 1 -- Somewhere in Germany there's a huge hole left behind by decades of coal mining. Eventually that same hole became a clear lake with divers below and birds above. That's Geiseltalsee in Saxony-Anhalt. The Global Nature Fund says the lake was mined for lignite in the past and was transformed into a thriving habitat in the roughly three decades since mining ended. The group named it the Living Lake of the Year on World Water Day 2023. That was the first man-made lake to win that title.

For generations, crews dug lignite, a soft brown coal, from the Geiseltal valley. Coal mining there stopped in 1993. What was left, the Global Nature Fund describes, was a hostile pit for life in a bare mining landscape.

And then a new plan w...