Hello zdeathbringer, welcome to the forum
First of all, I don't claim to be an expert on the environment or on economics, so please don't take this structure as law, I've just whipped it up in like 5 minutes. Secondly, in an exam I would instantly pick the opposite question even if it was international organisations (which I dislike almost as much as environment), because I think environment is a bit of a silly topic.
That said - here goes!
My immediate thought is to break it down according to the syllabus, so perhaps have 4 paragraphs (I usually like to have between 4 and 6, if you can split a paragraph into two, definitely split it into two). Also you will have to do some research on mentioning specific trends and policies, as I kind of ignored this dot point, hoping it wasn't going to be tested

1. General description of environment
- here I'd talk about what ecological sustainable development is, chuck in a Production Possibility Frontier (get some free brownie points)
- Then describe the trade off between the environment and growth (or other economic concerns)
2. Preservation of natural environments
- Talk ST reduction in growth, opposition from groups who might use the land for other purposes e.g. farming
- Industry faces higher costs from rigorous standards - disadvantages international competitiveness
- Cost of repairing environment born by tax-bearers, governments may wish to remain popular to maintain power
3. Pollution/Climate change
- You're probably better here than me haha
- Pollution is a negative externality, so draw a graph on that and explain what that means (again directly implementing economic theory which wins marks)
- Talk about the lack of cooperation on an international scale, which is what is required, because individual nations taking action places them at a disadvantage in short term growth
4. Depletion of natural resources
- Here the most obvious economic concern here is the mining industry, so I would mention the difficulty in fighting the mining companies, who receive large sums of overseas investments
- Talk about renewable energy here - Clean Energy Fund
So after all that, there is my answer to the question, again I really suggest you look at your notes and textbooks to make sure what I say is right. And hopefully you can improve on this structure and definitely content, but I'm sure there are a few pointers here that would be helpful for you

Good luck!