On the cake, the "good" ecosystem is on the right (because it's right) and the "bad" ecosystem is on the left. The negatives about air quality on the left are the particulate matter (sprinkles on cling wrap) and the coal dust (Oreo crumbs scattered) from coal mining for energy. On the right, the air quality is better because of the lack of particulate matter and the use of windmills as energy. The water quality is shown as "bad" on the left by the dead fish and the runoff from pollution (black icing in pond). The water quality is better on the right because there are mangroves (pretzels) growing by the pond and healthy fish. Climate on the left is a problem because of the clear cut section (Nutella patch) and the gas guzzling Impala on the road. On the right, climate is controlled more easily because there are plenty of trees (Tootsie rolls) and a Nissan Leaf, which is an electric car, driving. Waste on the left is bad because people choose to litter, leaving trash everywhere (Tootsie roll wrappers) and also because they have only trash cans (green Dots) instead of recycling bins or compost stations. On the right, waste is controlled (no trash) and recycling bins (green candy) are employed instead of trash cans, encouraging people to recycle.
I believe that the Earth will eventually look like neither of these outcomes, but a mixture of the two. For example, we might keep the fish from dying but still have coal dust everywhere. Conditions will improve, but they can also get worse and fluctuate. I think that as long as we strive for the "good" side, we'll be at least okay, if not perfect.
When baking the cake, everything went well. I had all the ingredients I needed, though figuring out what to use for mangrove trees was difficult. I made the cars and windmills out of paper (all one sheet) and the cardboard from a soda can box, as well as toothpicks. The trash shown on the "bad" side is actually the wrappers from the Tootsie rolls- the trash created making this cake was used on the cake. It took about 3 hours to make, not counting planning and shopping time.