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Garbage in, Garden Out, The Recycling Gardner Discusses Carbon
Two Basic Laws
John: OK Professor, I like the garden, everything seems to operate well, but you are a scientist, how do you reduce the garden into simple laws that explain things?
RN: Hmm, how about just two? There are two laws to understanding your soil, plants, and almost everything else. You know them, they are really simple, and really important but most people tend to apply them only to the field they are familiar with. You are a teacher, you should understand they apply to most things if not everything that happens. The good news is you cannot violate them, they are laws of nature you already know.
John: You mean the first and second laws of thermodynamics?
RN: Yes, the very foundation of all science and all laws of science. Let’s state them formally. The first one is this: Matter is not currently being created or destroyed. This is called the First Law of Thermodynamics.
Why is that helpful to my gardening?
Assume for a second that you need potassium in your soil to help your plants grow. Plants need potassium. Every cell of a plant needs potassium, so, when you peel a cantaloupe or watermelon, think about the potassium that is in the rind.
Right, there is potassium there! But what if I put it in the garden, say, in the compost or in the ground. This is where that really simple rule applies. The potassium, being a mineral, or a metal, isn’t going to vaporize, it will remain in the compost or in the ground where you put it.
Nitrogen, carbon, oxygen are different of course because they can turn into gasses and return to the atmosphere. But again, if they are in a plant of animal breaking down in the soil, most of it will stay in the ground until it is released by bacteria, fungi, or taken up in a plant. The soils do not give up carbon easily, but it does do so slowly, neither does water, nature seems to have a law that keeps as much carbon in the soil or water as possible because life forms need it.
John: OK, so much for the first law....
Orchid Cactus, Epiphyllum, or Nopalxochia, or Disocactus
The Second Law
RN: Here is the Second Law: Things are constantly reorganized, specifically they become less organized. This is always true.
Complex things like plants die and break down into simple things, unless it is alive and then a lot of energy is used to build it up into a complex item, but this still applies because the overall system is less organized simple because it takes a lot of energy to do this. This energy often comes from the sun where that disorganization took place and the heat left the sun as a very small percent of it reaches us on the earth. So the law holds.
I use this in the garden both for things like making humates or making compost where you start out with very complex plants (again, which used energy from the sun to build their complex structures) and then break down into thousands of slightly less complex things, then millions of even less complex things. In other words, things tend to get less organized unless something alive organizes them.
Humans are intelligent so I can organize my garden into something that looks nice, but if I leave it alone, it will degrade into something much less appealing. OK, this explains you kid’s bedroom, but how about the my garden?
John: I was just about to ask that.
RN: So the question is asked, is nature perfect, or the highest order of things or can intelligent life like ourselves create something prettier, more useful, or in other ways improve what is there? Well, let me talk you through three photos I have taken. One of a desert terminal basin that is, where water flows in but only evaporates as a way of escape. Salt is left in the soil (the law of conservation, again) and the only life is the occasional flying bug transiting the basin. The second is a rain forest in Sought Eastern Alaska where the trees live, then die and decay feeding the ground, and every few yards there is a shrub or bush, tree or fern. Lastly, and you ought to look up photos of this on the web, Butchart Gardens on Victoria Island, an incredibly beautiful garden.
Whether you like it or not, we do live in a world with natural hierarchies. By that I mean some things are better than others, just as some school are better than others, some boxers are better than others, and so forth. Having visited these three areas, I can say definitively that Butchart is by far the best place to be, followed in this example by the rain forest, and lastly, if you mush, the least attractive is the desert location. If you don’t like flowers or trees and do like dune buggies you are free to disagree, but that simply means you have a slightly different value applied to each, there is still a hierarchy.
So, can man improve on nature? Oh, yes we can, at points.
Can we help nature, as well as hurt it? Yes, we can.
So humans are not listless and helpless in the world, we can choose to improve things, but I digress, back to the second law. . .
Well, I was outside trimming a vine a while ago and a garden ornamental plastic frog fell off the small shelf and very rapidly disorganized. What was previously a frog ornament is now just so much trash. It took someone a fairly long time to make it, or to make the molds and plastics that were used to make it, and to paint it, then to ship it, sell it, and so on. It only took a second to make it less useful. Disorganization can at times happen swiftly.
There are lots of more helpful applications of this law in the garden besides my ornamental frog, or the compost or the garbage you plant in the soils. You see, even when a plant is using the sun’s energy to build up, it is still throwing off things it does not need. One of these is oxygen, but some plants give off leaves, twigs, even branches while they are growing.
Deciduous plants, of course, give off all their leaves every year, and all of this can be useful in the soil or on the soil as it breaks down and back to the soil it goes.
So here are two rules, actually scientific laws that help you understand how the garden works. And, yes, those rules apply all the time and every time a molecule breaks apart into a simpler molecule releasing (disorganizing) energy, and every time a growing plant uses the sun’s energy to build something into a larger molecule or a structure, energy is lost in the process, it always applies.
John: Now wait just a second, science? Back the truck up.
RN: This is really easy science. These laws actually explain how all physical things work at their most basic. All other scientific laws are based primarily on these two laws and one other which is less useful as long as there is any measureable heat and someone to measure it. I promise to tie this back to my garden. If you will just indulge me for a minute longer.
John: Sure, go right ahead.
RN: You see in the entire physical universe from the largest of things to the smallest things, everything functions by these two laws. There are others, but these are the big two.
Again, no matter is being made or destroyed right now, and things that are highly organized are becoming less organized.
These really are the two basic laws that all science is based on. Formally they are called the first and second laws of thermodynamics, that is, heat, or energy movement laws. They are really simple, but also very profound.
Later we will talk about how nature tries to preserve carbon compounds using these laws. Carbon is made into very highly complex molecules by plants, then, when it breaks down, there are really thousands of useful compounds produced, used, reused, broken down even further, made into new compounds, and so on and so forth. Carbon is biologically expensive and uses sunlight to be made into these even more expensive compounds, so try not to waste them.
John: In the garden you mean?
RN: Yes, of course. A plant uses the energy it gets from the sun, adds water and carbon from both the air and from the ground to make sugars which are then made into these very complex carbon molecules. If the plant doesn’t have enough, the energy is simply lost. So carbon in the air and ground is very important to your plants and you can help by putting it in the ground which really needs a lot more than it is getting, at east in your yard.
Carbon is continuously being exchanged in the atmosphere, geology (carbonates), water (bicarbonates and carboxylates) and in living things (all categories of carbon).
Let’s look at the cycles for a second. Realize also cycles happen with every element, but especially carbon, oxygen, nitrogen, and hydrogen.
How is carbon removed from the atmosphere? The primary producers of complex compounds made from carbon dioxide and carbon monoxide are green plants and green bacteria called (wrongly) blue-green algae. All of these are classified as photoautotrophs, meaning the feed themselves automatically via the sun and their removal of CO2 from the atmosphere is constant and the very basis for most life on earth through photosynthesis.
Bacterial fungi, and animals that consume plants in all forms, that is, degrade them, consume plants that are degrading, or eat the whole plant whether fresh, or dried, or frozen all get their carbon, sugars, starches, fibers from plants they eat. Plants synthesize sugars into oils also, so all oils compounds are derived from similar plant pathways, or other biologic pathways for simpler carbohydrates. All other organisms that feed off these animals and bacteria, fungi, are getting their carbon third hand.
In water carbonates and dissolved CO2, then carboxylic acid, attach to other things such as calcium (calcium carbonate) or other minerals to form useful elements for plant growth, for corals, and other organisms. The organisms fix calcium carbonate into more stable forms, and when they die, they end up in sands, fossils if buried fast enough, and are returned to soils as substrates in the oceans, or help to form clays or other sedimentary rocks.
Of some interest to our conversation is how oxygen play an important role in carbon cycling. You see there are two major uses in the fungi/bacteria world for carbon, carbon dioxide is one, the other is methane. If oxygen is present then the carbon compound breaks down into carbon dioxide which is immediately useful for plants but many thousands are useful before they break down this far. Of insufficient oxygen is present, but moisture is available, carbon is made into methane. Yes, swamp gas, which mixes readily with other things like sulfur to make various unpleasant odors, such as you had in your pond last year.
This is why, when you make compost, you need to turn it to expose it to oxygen, or have sufficient worms present to aerate the material and prevent the methane production which would naturally follow without the oxygen.
Now, you don’t need to promote the CO2 production, the microorganisms get more energy for their life by making CO2 that by making methane so they will make CO2 of oxygen is available. So the bacteria make less methane and your family and neighbors make less complaints and the FBI will not dig up your yard thinking someone is buried in a shallow grave. That is unless you have a Titan Arum in bloom. Did you see that large fresh mound as you walked in?
John: Yes, the ones with the worms all over it?
RN: Yes, I just buried a large pot of Turkey soup. The worms were from the mulch planted earlier, that soil is turning black with various humates and the worms are loving it.
Plants at the surface break down quickly according to their size, but lastly, carbon long buried as coal or petroleum is mined and burned returning some of this carbon to the atmosphere from where it came, or, if in a plant, the plant died, degrades and returns the CO2, or from animals using the sugars for energy, burn them and create CO2 which they then exhale back to become part of the .032% to .038% of the atmosphere according to where you take the readings and, quite literally, which way the wind is blowing.
Now, you complain, when you burn coal or gas, all of the CO2 is returned to the atmosphere, not just some of it. Let’s assume for the sake of argument that you have perfect combustion and all the carbon is burned, then you may be correct it might all be CO2, but usually there is ash and ash is mostly carbon chains while CO2 is mostly oxygen. However, in the ground, once all the petroleum oil is pumped out. There remains there more than 50% of the original carbon. This is why oil companies use things like steam or hot water to force out more oil from the ground and why it works.
So there is the principle, soils do not give up carbon easily. Some of it almost always remains in the ground. And for this discussion, that is where we want it.
Now, I don’t want to take sides on a controversy as large as the controversy called Global Warming because frankly, all the data is not in yet, and frankly, you are damned if you do and damned if you don’t, but the carbon cycle is a part of our everyday lives regardless of the side you choose, and we can all agree that natural carbon in the ground naturally is a good thing.
So what I advocate is the uncontroversial addition of carbon into the ground to help the soil and help plants take up more carbon. Everyone agrees that improves things since a nice green yard cools off your house and neighborhood since plants absorb heat from the sun. That green in the plants comes largely from carbon in your soils and the CO2 which plants draw out of the atmosphere.
One way or the other you have to agree that CO2 is a greenhouse gas, that is, it prevents the earth from freezing at night and during the winters, and since CO2 makes up less than 1/3 of 1% of the gas in the atmosphere, this self balancing system here on earth is pretty remarkably balanced. There is some debate as to whether it is a cooling gas, a buffer gas, or a warming gas, but again, I won’t go there.
Again, what I advocate is adding carbon into the ground to help your plants grow faster and so your soil is rich and dark and filled with carbon compounds. No controversy there at all.
So that is, in very brief terms, the carbon cycle in your garden explained with just two laws of science. Are you sorry you asked?
John: No, that was quite good, but a lot to think about. How about those Irises!
© 2015 Ronald A Newcomb