ximenez, you make a great point!
Many "libertarian" systems proposed are just slight modifications of the current system. At worst, they are just the abolition of the income tax.
The solution to your problems is this: sell it. Ponds and the atmosphere currently belong to "the public", and so are subject to the tragedy of the commons. However, private property does not face this problem.
A (non-libertarian) criticism of my argument is "You CAN'T sell the air!" However, this displays an ignorance of basic economics. Economics is the study of limited resources. We humans are limited in what we can achieve. We have to make trade-offs. The great benefit of a common currency is that these trade-offs can be numerated. Thus, using the principles of economics, we can objectively see what we are gaining and what we are losing.
An example: There are three "users" of a lake
- BigEvilCorp - widget maker, polluter
- MomAndPopCo - friendly fishermen
- The Town of Quantville - local rustics
All of these need to use the pond, whether for dumping, fishing, or beauty. The current statist sollution is to have "the people" (meaning a government) run it, and decide its use based on political power. The libertarian solution would be to privatize it. Call this profit-seeking entity Pond Ltd.
Pond Ltd. wants to make as much money as it can. As such, it requests bids. Assuming MomAndPopCo and Quantville selfishly band together (as they would in a libertarian system) for their own self-benefit, one of two things happens.
- BigEvilCorp out-bids MomAndPopCo and Quantville. BigEvilCorp's customers continue to buy whatever the company sells at low-low prices. Fishing drops to nothing. However, because use of the lake is guarenteed, and use doesn't have to be shared, economies of scale can be realized. The low cost of widgetes help society in general (adding to social welfare), and the poor in particular (lower costs work the same as a regressive negative income tax).
- BigEvilCorp loses the bid. MomAndPopCo's and Quantville's bid for the pond wins. BigEvilCorp goes out of business. Though production is limited, more fish are available. Because the fishery doesn't have to share the lake with a polluter, economies of scale can be realized. Further, the people of Quantville "consume" the wonderful pond everyday. This increases the social welfare.
"But what about the environment? What if Quantville and MomAndPopCo are poor?" Well, if outsiders actually care, they will prioritize. Groups like the Sierra Club will pay to keep rivers and lakes clean. The only difference from the current regime is that this money would be directly spent on action, instead of lining politicians' pockets.