Survival of our species/Reducing our impact on the environment
We are part of our environment and have the capability to change it drastically. We are probably not at risk of extinction due damaging the environment but there are plenty of other species that are. The world becomes a poorer place due to our negligence.
Acid rain, ozone depletion, air pollution, unsustainable destruction of rain forests, carbon dioxide emmisions and global warming, increasing environmental destruction due to both urbanisation and agriculture are all examples of large-scale changes we have made directly to the environment that hugely affect wildlife and reduce our own quality of life. Currently we only have one home and on behalf of all life we should protect it.