Global Warming - Developed & Developing Countries All Are Responsible

In United Nations Climate Change Conference, World Nations are agreed to reduce Carbon emission in significant amount by 2020. Developed nations already polluted environment and now underdeveloped nation doing them same. Question here is, Do developing countries learnt any lesson from situation? Day by day trees are cutting in faster rate in developing countries. In my own city, rate of tree diminution is in extreme. In 1991, Green population in my city was 36%. Now, it's reduce to 7% and its expect further reduce to 3% by 2020.
What developing countries are doing to fight their Global Warming problem?

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Thanks for Image, article content from Wikipedia & Times of India