For the most part, environmental values come into conflict with economic values. They can also come into conflict with the value of personal liberty.
As an example of the first, think about the idea of a carbon tax. Such a tax would tend to reduce pollution. However, many people think that it would also raise prices on energy and hurt the economies of countries that imposed it. In this case, the value of environmentalism comes into conflict with that of economic prosperity.
As an example of personal liberties, think about the ban on incandescent light bulbs. Some people simply like those bulbs better and want to be allowed to have them. This desire for liberty comes into conflict with the environmental values that tell us we should not use light bulbs that are not energy-efficient.