Oh if solving climate change was so easy! No, that idea doesn't work at all. For any of these ideas you need to look at the total CO2 spent vs CO2 removed. It

Oh if solving climate change was so easy! No, that idea doesn't work at all. For any of these ideas you need to look at the total CO2 spent vs CO2 removed. It doesn't matter that you're creating a sink (dumping plastic in a big hole) if while creating that sink you're emitting even more! Plastic comes from oil. Oil extraction already releases a lot of CO2 to begin with. Making the hole and dumping things into it takes CO2. Not recycling means using even more oil. Not all carbon is the same. You cannot make plastic out of a pile of carbon efficiently. If you could, we could just reduce the plastic to carbon and make new plastic. This means that you cannot make plastic out of atmospheric carbon efficiently. You need your carbon to already make small chains (like ethylene and propylene). These small chains are then linked up to make plastics (polymers technically). As for doing it from trees, it's not so simple! You cannot use much of the three. You need to spend CO2 to plant the trees, take care of them, water them, harvest them, process them. This idea doesn't work at all. The best way to save CO2 is to reuse, not to use more.