Preservation vs Conservation

Earth Day Wallpaper Source: Fun Gallery Images
So Earth Day has passed a while ago, but with a lot of people and businesses going green lately and having started to read Tony Juniper's book "What has Nature Ever Done For US? Does Money Really Grow On Trees?" I have really really been thinking about a lot about Mother Earth.  Mainly the growing debate of whether we as a society should preserve global resources or conserve them in a suistainable way?

Conservation is the way in which humans use natural resources for the benefit of economic utilization. Whereas, preservation suggests low human involvement of natural areas while still managing the development of natural processes and the number of species (plant or animal). 

I can understand a conservationist point-of-view whereby sustaining ecosystems can benefit many species from extinction in terms of predation or competition and help humans harvest an appropriate yield that can be managed over years.  However, I can see the preservationist point-of-view where naturally regulating areas such as Yellowstone Natural Park has allowed more biodiversity than managed glasslands and preserved the lands aesthetic and spiritual values.

However, in times where global warming (caused mainly by humans) and natural disasters are heavily effecting biodiversity and causing the endangerment and extinction of various species, is preservation really the answer? Don't we also need conservation to ensure that more species of plants and animals are created for the future?  On the other hand, in times when the global economic crisis has deterred governments from seeing the worth of convservation and has reducing aid to conservation organisations, are efforts made really enough?  Also, if we were to implement just conservation techniques, how do we prevent business monopolies and the rich from benefitting from something that should be for all humans and provide economic justice.

So, I suppose what I am asking is "Preservation better than conservation? Or can there be a balanace between the two?"