We've seen that it is far from clear how anyone could come to have an absolute property right in the first place, and that this is a huge problem for rights-based defenders of capitalism. Perhaps one could appeal to some form of Rawlsian or utilitarian principle in the initial distribution of natural resources, to ensure that everyone gets a fair share. But what about people that aren't born yet? It seems unjust to exclude them from consideration. Yet, if they're included, we'll have an indefinite number of people to share our natural resources around, so there mightn't be enough for each to have any!
An absolute property right entitles the owner to dispose of their property however they wish -- even destroying it, if they so desire. But surely it would be a gross injustice for the present generation to destroy the world's natural resources. We cannot have any such right. So we cannot have absolute property rights. A better conception would involve provisional property rights. The idea there is that individuals are granted use of resources, so that they - and others - might benefit. But they do not have full ownership -- the state may take the resources back (through tax) when others have greater need of them, or when newcomers join the system.
This view is also much more environmentally friendly: we are seen as custodians rather than owners of the planet. We have no right to trash it, for the world belongs as much to future generations as it does to us. As such, our current behaviour (in terms of pollution and other natural vandalism) is incredibly unjust. We all think it's wrong for a pregnant woman to recklessly endanger her baby by allowing toxins (booze, smokes, drugs) into her system. Yet here we are, pumping all sorts of toxins into the ecosystem -- similarly reckless behaviour which will likewise cost the next generation. What is wrong with us?