I was a bit discouraged to hear that the CO2 the plants remove is ultimately rereleased into the atmosphere when the plant decomposes. So I’m wondering what positive impacts I’m making with my backyard garden, if any.
Also, with millions of gardens, would they really be totally useless for CO2 removal? Or is there some small amount that gets captured by the plant and then *not* rereleased into the atmosphere, in other words, permanently removed from the air?
In: 4
They can’t do much for CO2 levels, but they can help butterflies and local mason bees. Local and native flowers matter and it doesn’t take much to make a difference.
If anything most gardens only make things a tiny bit worse.
The carbon of the CO2 gets stored in the plants.
It is bound up in the carbon is bound in the wood and the leaves of a tree for example.
If you burn the wood later it will release the carbon again.
If you let dead plants rot it will release the carbon again.
The carbon doesn’t stay bound. If you want to bind more carbon you either need to increase the overall mass of plants dramatically or you need to sequester plantmass in the ground in a way that will make it stay there long term.
Peat bogs are a good way to do to that, but most people don’t have those in their gardens.
What they mostly have is lawn and they mow that lawn. and either burn or compost most of the cuttings.
This is a useless mono culture that does little good for the environment but suck up precious water that might be of better use elsewhere.
Best case scenario is a vegetable garden. That won’t help capture carbon since you eat all the vegetables and exhale the carbon as CO2 again, but at least less fuel is burned transporting food around.
> the CO2 the plants remove is ultimately rereleased into the atmosphere when the plant decomposes.
Well, you got your own answer in there: just plant something that will last long enough until more people plant more stuff that last long enough until we all die.
One big tree could potentially store 50% of it’s mass as carbon, if said tree’s lifespan is about 100 years that means you have 100 years to plant another two trees that will absord all the carbon from the initial tree plus a little more. Just keep repeating this and you will end up with a “carbon forest” that could potentially store tons of co2 for years and when you die that will be someone else’s problem 😉
Your backyard garden does very little directly to affect CO2 in the atmosphere, and sadly, the same is true of the sum of all vegetable gardens, for just the reason you mention. One way plants help remove CO2 from the atmosphere by using the carbon from it as building blocks for their energy reserves and cells. When those are consumed, whether that’s in the form of being eaten by bacteria in your compost pile or being eaten by you in the form of a delicious ratatouille, or being eaten by voracious wildfires, the thing eating them – whether bacteria, animal, or inferno – releases that carbon back into the air in the form of CO2.
That said, all hope is not lost. Growing your own vegetables can be at least a little helpful to the atmosphere not because of the CO2 they sequester, but because of the CO2 you spend to get them. If it takes X amount of fuel to get your seeds and all your gardening supplies, but you save more than X amount of fuel by not needing to make a trip to the grocery store for your vegetable needs, that can be a very, very, *very* small but still positive change for the air. You are almost certainly not the primary cause of climate change, but every little bit does help. Save a trip, save a dinosaur, as it were.
Think of it this way. The amount of CO2 the plant removes from the atmosphere gets put back eventually. But that CO2 is removed for a bit. And in that bit it’s a (very) little cleaner.
But don’t think about the garden itself. Think of the CO2 of the massive farm. People driving to work at the farm. Farm equipment. The farm it took to produce the seeds for planting. The CO2 at the factory that made the farm equipment. The CO2 made to transport the farm equipment. Etc.
A small garden isn’t going to remove waste CO2 from something as large as this planet. Just isn’t happening. And anyone telling you that is probably selling garden stuff.
The environment is affected by many things. CO2 is a big issue, but it’s far from the only one. Of the top of my head I can think of two real tangible benefits:
**Temperature regulation:**
Plants make the area around cooler. They do that by shading, and by evaporating water. A garden can be several degrees cooler than the parking lot next to it. This reduces the need for air conditioning which uses up lots of energy and creates pollution.
**Biodiversity:**
A healthy environment has many different kinds of creatures living in it. The more different types of things live in an eco-system, the more stable and resilient the system will be. If a dieses kills one kind of pollinator, there are others. If weather destroys 90% of some plant, animals have other stuff to eat – so the whole thing can bounce back from incidents like that.Unfortunately, humans had a fashion of planting just grass on big areas, or make rows and rows of the same type of tree and so on. This weakens the local eco-system, making it more and more difficult for other thing to survive and creating a chain reaction – cause everything is holding everything up like those annoying trust exercises where everyone leans on each other in a circle and nobody falls.When you plant a garden in your back yard – and you do it right! with local plant species and a bug hotel and no poison pesticides – you help the whole system recover. You’ll get lizards, bees, grasshoppers, birds, beetles, possibly frogs and so on. Now those creatures have a place to start recovering their population and make the whole area thrive.
**Extra small benefits:**
– Any food you grow in your back yard wasn’t packed in plastic and shipped in a truck
– Some types of plants can be used to purify water and air from various pollutants
-People roll their eyes at “awareness” as not really doing anything, but it’s the first step. If it made you ask the question and think of real climate benefits, it made other people think about that too.
(edited for formatting)
What you need is a carbon sink. A place where it doesn’t biodegrade. Bogs are natural carbon sinks, the lack of oxygen means things that would rot in months or years can last for millennia.
You could make an artificial carbon sink and that may be a necessary part of carbon capture technology.
As long as a plant is alive it holds onto some CO2 that would otherwise be in the atmosphere. This means that as long as you keep replacing the plants in your garden with new ones when the old ones die, your garden is keeping some little CO2 out of the atmosphere. Sure, the CO2 absorbed by your plants gets re-released whenever your plants die and are decomposed, but every new plant takes up CO2 again. So in that sense, the world does have a tiny bit less CO2 in its atmosphere thanks to your backyard.
Having said that, it depends of course on what you assume would be there instead of your garden. If you compare it to a tiled-over backyard, then yes, it’s a net benefit. But if you compare it to simply letting nature run its course, then likely the same patch of land would have been fully overgrown, and thus would have captured *more* CO2. So regarding your last question: millions of gardens *aren’t* having a net benefit in the sense that those patches of land would almost certainly have had plants growing on them anyway, and likely more than they do now. However, if the choice is between planting a garden and just putting down some tiles or gravel or whatnot, then the former is definitely the better choice, and not even so much from a CO2 perspective but more from the point of view of biodiversity, water management and (counteracting) urban heating.
To my knowledge, plants only permanently capture carbon in the ground under rather specific circumstances which you will not find in your avarage garden.
If you think about the big picture, there is a certain amount of carbon in the planets biosphere (air, soil, oceans, etc.). The only natural thing that increases this amount is volcanoes. Whatever natural processes exist to remove carbon from the biosphere altogether, as in transport it into the depths of Earth, must happen in the same order of magnitude, otherwise the amount of carbon would just naturally decline rapidly all by itself.
Unfortunately, us humans are introducing carbon into the biosphere over 100 times faster than volcanoes do. Since we cannot expect the natural processes to just become a hundred times faster, nature will not fix this for us. (Unless we’re talking about the *very* long-term)
There is however one thing we can do, at least as a band-aid: When a tree is old and about to die, instead of burning it or letting it rot, we can use the wood and do something to preserve it. For example, we can use the wood to build wooden buildings. That way the carbon will be stored in the wood long-term.
Of course, this wood will also decompose and release the carbon *eventually*, but at least we can buy time to come up with a permanent solution this way.
Latest Answers