The classical solution to the tragedy of the commons for rivalrous goods is propertization. It's the logic behind contemporary land rights, some very successful commercial fisheries management (north west Atlantic), and emissions auctions in the US (SOx and NOx implementation - but notably not the proposed carbon, which has other wierd factors bolted on)
That's why you introduce a land value tax. As the supply of interested parties increases, so too does the demand and therefore the value of the land. This has several effects:
1) incentivizes unproductive land owners to sell
2) incentivizes productive land owners to seek tenants
3) generates public revenues to offset negative externalities
That never seems to get mentioned at the time the commons are privatized, only in salons later on. Also, it's rather hard to build capital improvements on fisheries, and correspondingly this does nothing for the preservation of wilderness. which is a problem that privatization is supposed to solve but frequently doesn't.
