Yes certainly all the evidence suggests that these changes are mainly caused by humans. But that's different from saying that global warming is the sole cause of these other environmental problems. If that is what you're suggesting than the logical conclusion is: if we stop global warming than we can instantaneously solve all these other environmental crises. That simply isn't true thought because each is caused by a multitude of causal factors that amplify each other.
I'll give you a bit of perspective on what it would take to solve global warming, and then tell me if you're ready to take all necessary steps to stop it:
"According to a new report published by the United Nations Food and Agriculture Organization, the livestock sector generates more greenhouse gas emissions as measured in CO2 equivalent – 18 percent – than transport. It is also a major source of land and water degradation."What does this mean. If scientists and politicians and those who believe in the danger of global warming truly want to end it they must take meaningful and dramatic steps towards lowering or eliminating livestock production. I highly doubt many people would sign up for this though.
http://www.fao.org/newsroom/en/News/2006/1000448/index.html