I know that one of the suggestions as to how to become more carbon neutral or carbon friendly is to plant trees to offset the things you do that lead to the production of greenhouse gasses, but I’m not entirely sure how that works. I mean, I understand the carbon cycle. Photosynthesis breaks down the carbon dioxide, the plant using the carbohydrates produced to grow, and the carbon goes out of the atmosphere.
But, and here’s what I don’t get…the tree will die and rot, or get eaten by some animal, and then all the carbon in the wood is released back into the atmosphere as carbon dioxide again. I’d understand it if the plan was to plant the trees, then cut them down and bury them, but as it is, isn’t planting trees to offset carbon usage a waste of time?
Correct, the dead tree will rot and release CH4… Wherever you put it…
Ynless you sequester the carbon by putting the wood down in a cave or something, and preventing it from decomposing (no living organisms…), …
If you use the trees carbon/carbohydrates as fuel or building material, AND that saves on fossil fuels… there’s a saving.
I think the idea is that by planting trees you’re helping to reverse deforestation. Deforestation tends to increase CO2 and burning fossil fuels also increases CO2. On a personal scale, it’s really difficult to reverse the latter and relatively easy to reverse the former.
Kinda like, if you felt guilty about running over a dog with your car, you can’t magically bring the dog back to life but you might try to make up for it by going to a shelter and rescuing a dog that was about to be put down. The fact that the dog you just rescued will eventually die anyway doesn’t make the gesture pointless. But this plan only works if there’s a shelter with dogs about to be put down. If there are no such dogs and the shelter does not exist, then this plan won’t work. Likewise, planting trees only works if you live in a world where there’s a shortage of trees because too many were cut down.
There is a steel mill in Brazil that uses charcoal (instead of coke from coal) in their blast furnaces. They manage their tree consumption, with square miles of tree plantations that get harvested about every 7 years. Because the charcoal does not have the Sulfur contained in coal, the resulting steel is naturally very low in sulfur. They advertise a zero-carbon footprint.
Now, there are square miles of rainforest that now only grow a single variety of tree, instead of jungle, so there isn’t the diversity of life (vegetable or animal) that was present in the jungle, but they did eliminate the use of coal and actually produce better steel. It works.
Some (but hardly all) kinds of forests do act as net carbon sinks. While each tree will eventually die and rot, returning the temporarily sequestered carbon to the atmosphere as carbon dioxide, some of the carbon can be buried in the soil where it will accumulate. When it is buried deep enough, microbes that require oxygen will not be able to further decompose the rotting wood, and a fraction of the tree’s carbon can be permanently sequestered.
Your average backyard suburban tree, on the other hand, isn’t going to be left alone to die and get buried by more dead trees. That tree is going to be chopped up and turned into mulch or firewood, neither of which will sequester any carbon for significant amounts of time.
Tangential question question: what happens to carbon in landfills, where a lot of wood products end up? There must be extremely rapid decomposition at the surface, but most is buried far too deep to have any source of oxygen. On the other hand, I bet there’s a lot of anaerobic decomposition made possible by the rich chemical soup in our garbage.