Ringsjön was badly damaged by agricultural run-off in the latter half of the C20th and the start of the C21st, with runaway algal blooms in summer being just one of many problems. Quite aside from its role as a reserve source for fresh water distribution to cities to the west and south, the chemical imbalance of the water—and the consequentially imbalanced fish populations—was doing terrible damage to a unique ecosystem*. While things are far from fully fixed just yet, many improvements have been seen as Sweden’s agricultural practices have shifted away from industrialised monocultural approaches.
None of this may be of interest or even notice to you, should you find yourself walking or cycling around Ringsjön’s peaceful shores (and you really should). That said, keen anglers may want to keep an eye on the regional website which lists bounties on particular sorts of fish: not only do you get to indulge your preferred hobby, but you can help to restore an ecosystem while you’re doing it, and maybe even earn some beer money.
* Nonetheless, we would like to emphasise that none of this presents any risk when it comes to drinking tap-water in Skåne; likewise, the water of Ringsjön is very unlikely to do you substantive harm if you drink it directly, but we’re told it’s not exactly a pleasurable experience, so fill up a bottle to tale with you, eh?