Not much really. We continue to harm the environment by development and try to do a small bit to rationalize it. An example is the electric car. It is always advertised as an environmentally-friendly alternative since it does not release any air pollutants. However, we never pay attention to the source of this electricity, and more often than not it is still being generated by burning fossil fuels. So we are just trading the source of emissions and not protecting the environment. Similar is the scenario with eco-tourism. On the one hand, we are trying to cause minimal damage to the environment, on the other, we are introducing new areas to tourists.
In fact, the term 'protect' is a misnomer when it comes to the environment. Webster describes protect as "to keep (someone or something) from being harmed". When we look at how we are trying to protect the environment, it seems we are trying to decrease the damage that will be done to the environment by our actions and not actually protecting it. Protection would mean improving the existing conditions or ensuring that the conditions improve from the current baseline. I agree that efforts such as afforestation and wildlife protection are helping us 'protect' the environment. However, the environment is a global issue and as a whole, human beings are not doing their bit to protect it.