Hello
In English, because it concerns all of Switzerland:
A short summary of what happened: Netzwerk Schweizer Pärke has imported parks for which they have the polygons, with appropriate attributes. Unfortunately most of the parks boundaries overlap with already available communal boundaries, leading to ways on top of each other.
Now the Netzwerk Schweizer Pärke has asked if someone could help with reverting their import, until they have time to do the import properly, and I have now started to clean up this import, processing the first four parks. What I did is documented here: http://wiki.openstreetmap.org/wiki/User:Datendelphin/NetzwerkSchweizerPaerke... (in German, sorry)
For any objections or remarks please reply in this thread.
Thank you to the Netzwerk Schweizer Pärke for the cooperation.
Regards Michael