too much nitrogen in our planet's ecosystem??

I had been ignoring the Haber-Bosch process for years.  Ignore the problem, focus on solutions, try to move forward.

However, I realize I had been making an assumption, which was that nitrogen, once fixed, didn't stay fixed.  I assumed, since industrial farmers re-applied huge amounts of N fertilzer  each year that it was because the nitrogen got released back into the atmosphere--through poor handling of our human waste perhaps, I'm not sure quite what I thought.  

In fact, the only thing that releases the fixed nitrogen back into the atmosphere in any quantity, from what I can gather, is other microbes.  Fixed nitrogen stays fixed (solid).

Now, I'm realizing that it's a much bigger problem than I'd thought.  Having too much nitrogen in fixed, solid form cycling through our ecosystem in general.  Burning (cars, power plants) also release some in the form of partly-fixed NOx and other noxious, greenhouse-gas-property forms, and it seems this also gets into the nitrogen cycle, in a destructive way.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1247398/

This article is a good overview of the problem, albeit with some bias in my opinion.

In my garden I have kept looking at ways to keep nitrogen on the land.  This is still a good idea...better than putting my pee in the wastewater treatment plant, or in a river that would help algae blooms that then kill the water (de-oxygenation) and other imbalances.  But  I wasn't thinking about where that nitrogen came from originally...even though I eat "organic" as much as possible, the organic farms and gardens may use material that came from restaurants or lawns...that somewhere back in the process was haber-bosched out of the atmosphere (artificial fertilizer).  If you use blood for fertilizing on your organic farm, what did that animal eat? where did the nitrogen come from? it's almost unknowable.

(The Haber-Bosch process, vastly increasing production since the early 1900's, and continuing to escalate today) basically takes energy and turns it into bio-available (reactive) solid-form nitrogen.  It is a human intervention; it did not exist in nature in this way until we created it.  I've heard, and the article says, that approximately 80% of the nitrogen in humanity's bodies today was fixed by the Haber-Bosch process, instead of by microbes and occasional lightning strikes, the old way).

If I want to be responsible as a permaculturist to the whole planet, then I might think twice about planting more nitrogen-fixing crops.

It's a less obvious and less immediate issue than CO2 pollution, but, it's another responsibility.

Instead of planting more legumes and black locusts, maybe I should look for ways to take more nitrogen out of the cycle.  Ideally, I could go down to the bottom of a river and snag some of that extra nitrogen where it's causing imbalance and redirect that...but that's not viable to travel that far very often.  My nearby rivers (the Charles and the Mystic) don't appear to have any algal blooms; there is not much agriculture in MA State).  As far as what I should do on my own part of the land, putting haber-bosch nitrogen into the soil by way of my own body's outputs seems more appropriate than planting more nitrogen fixers, at least until humanity reaches a more balanced point in relationship to our ecosystem.  Taking compost from nearby flows can also be a way of contributing to net balance.

The other aspect of this question (and the one I started out asking myself) is, Does more fixed nitrogen allow for more carbon sequestration than before human intervention? the article cited says the jury is out; too much nitrogen in an ecosystem seemed to favor plants whose leaves decomposed more quickly, releasing their CO2 back into the atmosphere).

However, I can think of ways to put the nitrogen to use.  If you take that to the deserts and green the deserts, in theory you could be turning two problems into none: the deserts can capture more carbon than ever, and the fixed nitrogen no longer contributes to human food supply and population overbalancing.  

I couldn't find a post about this topic on permies yet, but I'm sure it's gotten discussed somewhere.  I'd love to see more conversation about this.  As the article mentions, CO2 gets all the focus, but the nitrogen- (or poop)-carrying capacity of the planet also needs to be examined.  Yes, nitrogen is abundant in the atmosphere, we're not going to run out.  But we may make the planet uninhabitable for other forms and for ourselves.

There are two questions--where the fixed nitrogen is  on the planet, and how much total of the nitrogen is fixed vs. atmospheric.  

Thoughts?

Nitrogen has been bandied about for years in the micro world, to date, no one has been able to actually show through experimental data that it is something to address with diligence, it may or may not come to pass.

The amount of energy required to gather up and move supposed deposits of Nitrogen compounds makes that scenario not a particularly good method, since you would burn fuels thus further adding to the Carbon foot print instead of reducing it.
If you have a good microbiome thriving in your soil, nature is already working to convert free carbon and free nitrogen into stable compounds (which by the way, once stabilized can be thought of as being inert since stable compounds are not going to break apart on their own).

The real problem is that every report about Nitrogen is from the chemist point of view which means that any thoughts about microorganisms doing their work has been cast aside in favor of raw chemical concentration data.
So, is there really some sort of nitrogen glut happening in non-conventional farming? probably not, but it is definitely going on in fields where "modern method Agriculture (mono crop with chemical additions to the soil) is practiced.
This is the land that really is in need of in depth study since this is where N,P&K are being added without consideration of a microbiome working in the soil, this is mostly because the farmers are wiping out their microbiome every time they run a disc or plow over their fields.

When we talk about the planet as a whole, the question can be asked, "Is this a process that can be dissected and looked at as a single entity or is it something that has to be looked at from the circle of life POV?
The jury is still out and until we do experiments designed to give the whole picture, we are not likely to come up with the viable answers.

Odds are that any nitrogen surplus is bound up, not available to any organism without the help of enzyme producing bacteria to break those stable electron bonds.
It puts Nitrogen in the same place as sequestered carbon when you start trying to do comparisons or extrapolate the numbers into available and not available amounts.
Then there is the question, Is nitrogen an element that helps hold heat in towards the planet and thus helping to increase the surface temperature in the same way we know CO2 does?

Fortunately today many more people are entering the discussion and pointing out discrepancies that have been created by the experimental methodologies being used for these studies.

Thanks for bringing this up Joshua, good questions and the discussions will be very interesting to read.

Redhawk

From what I've gathered reading heaps of articles this year, the big problems are directly or indirectly linked to N fertilisers, such as urea, and the harm is in the dose. N fixers just don't put enough quantity or concentration to upset balances, and from a climate perspective the creation of NOx (especially N2O) is very much a function of the methods of conventional agriculture. As Kola Redhawk points out, if you have a healthy soil microbiome, things will take care of themselves.

Synthetic N overapplication creates the conditions for ammonification, denitrification and N2O production in soils. These processes are not something we want in our growing environments or our atmosphere. The conventional ag approach to N is like feeding someone a massive amount of junk food: simple carbs with no real nutritional value. The result is what looks like high productivity, but is just vegetative obesity, and those plants are not going to be better for us or our livestock to eat.

hau Phil, good post, don't forget that another issue is acidification of the soil the Urea or what ever nitrogen source is applied to.

I've had to rejuvenate over 10 thousand acres of farm lands because the farmer applied too much N and acidified the soils they were farming.
When that happens, the "normal" crops won't grow or produce very well. (acidification of those fields put the pH down to 3.4 and 3.7)

The Big Ag. chemical companies have really done everyone a major disservice with their poisons and fertilizers.
I recon it will take at least 20 years from today (if all the farmers were to instantly change tactics to at least organic methods).

Redhawk

Thanks Dr. Redhawk and Phil,

This puts it in some perspective, and it's good to remember it isn't all a material-chemical process but a broader one.

I think the question boils down to, for me, in the city, using food scraps from nearby sources (and much of that nitrogen may have originated in a synthetic process some generations back, so hopefully it's reducing the need for further damage to be done) and my own body's outputs, vs. planting N-fixers.  If I am trying to err on the safe side of not to making more than my share of the amount of fixing of nitrogen, it makes sense to lean toward using the flows of food scraps local to me (i.e. within walking distance or biking.

I also gather that the role of n-fixers in a food forest is really at the start (the first five years or so), and after that N can be cycled through (via humans and animals) and the N-fixer trees chopped or shaded out.  I hadn't thought of this in terms of time.  If that's so, then the N-fixers I put in my landscape can be considered a transitional measure and not a permanent one.

Also, the idea that nitrogen can be inert in soil makes sense to me.  In some cases it acidifies soil or imbalances things, and can even make it impossible for anything to grow in huge overdoses, but I think burying some food scraps in "worm towns" is appropriate and may put it in deeper soil where it is more inert.

Overall, the problem seems more to be about distribution than about total quantity.  With CO2, we have a quantity limit--the gases are all going to spread out throughout our atmosphere.  Not much uneven distribution going on there.  With ground nitrogen (solid- or liquid-form nitrogen in the ground) it isn't going anywhere much.  Redistributing might make sense, but not returning it to gas form.  (If I lived at the bottom of a river with algae blooms then maybe I could help the overall balance by taking some of that nitrogen away or balancing it with sawdust or something...but trying to vaporize it would be going about it the hard way...off topic, what are algae's natural predators anyway? jellyfish?)
--
What I'm still foggy on, and the internet isn't making clear--where does the nitrogen go when you burn wood or plant matter?  some of it can make NOx, etc., at high temperatures (2600 F, if I recall), but mostly stuff burns cooler than that.  Where does that nitrogen go??  And what's off-gassing when ammonia stinks? Thanks!

Great thread.  Thanks for starting it.  A couple of thoughts.

1.  It's a closed loop system.  Like carbon, it's not that there's too much nitrogen in the system (the greater planetary ecosystem), but rather, too much nitrogen (or carbon) in certain places within the system.  Where much of that carbon used to be locked-up in the ground, now it's floating in the atmosphere.  So it's not like we are creating more nitrogen within our planets atmosphere, but we've found ways to artificially take that nitrogen and concentrate it in places (the top 6 inches of soil throughout the midwest) where it never used to exist.

2.  I think there needs to be a distinction between synthetically created and intentionally applied nitrogen (as most farmers currently practice), as opposed to naturally fixed nitrogen as a result of plants and bacteria.  Perhaps someone can correct me if I'm wrong, but there is no danger of the Mississippi river system becoming saturated with too much nitrogen because people upstream planted millions of nitrogen fixing trees and legumes.  Currently, the nitrogen run-off that has created the dead zone in the Gulf of Mexico is directly attributed to synthetic fertilizers dumped on fields throughout the midwest.  No such phenomenon would happen if millions of honey locust trees were planted tomorrow.  The exact opposite would be true: the millions of acres of crop land would become a giant nitrogen sink (and carbon sink) as it was during the days before widespread cultivation destroyed that ecosystem.

3.  While the problems are massive (global warming/climate change, as well as ecologically killing nutrient run-off), the solutions are surprisingly simple.  Planting nitrogen fixing cover crops, animal integration to graze farmland, no-till cropping, multi-species cropping, and other strategies are increasingly being adopted by farmers, and these strategies immediately make a difference.  While farmers like Gabe Brown are currently in the minority, the wisdom of their farming practices is undeniable.  As farmers increasingly adapt to these natural strategies, the problems will go away.

4.  Further, while these solutions are surprisingly simple, that doesn't mean that they are ineffective or "settling" for minimized yields.  When farmers adapt to holistic soil management practices (like cover cropping, intensive grazing and using nitrogen fixing plants), their profits go UP, not down.  They quickly understand that this kind of agriculture is not about being sustainable, but being regenerative.  Every year the crops are stronger and the yield increases, while the soil gets better and better.  

I am pretty sure we should plant more nitrogen fixing crops.

Ruminant livestock poo 85% of what they eat back out, so there is always a 15% defecit on nutrients per year. Grass will take x amount of NPK to grow, and my nutrient management plan shows my pastures are about 50 pounds of nitrogen per acre shy. I have to get that 50 pounds somewhere, or 100 pounds every 2 years, or 150 pounds every three years...well you get the idea.

I can buy Urea and get this, but I feel planting fields into 50% clover can get me tht 50 pounds per acre per year without doing a thing, just making a good choice on what to plant for a grass mix.

Thanks for the replies.

I realize I want to post the question i had had before my original post--if we humans can deliberately fix nitrogen much faster than nature had by using haber-bosh AND if there is 80% nitrogen in our atmosphere AND a plant only needs a few percent nitrogen content to fix a much higher mass/percentage of carbon, then might the answer for carbon capture, transitionally (not pemanently but transitionally) to use haber-bosch--in other words use every tool we've got (haber bosch as well as nitrogen-foxing plants (microbes) and keeping our poop and yard waste from breaking down with the nitrogen getting lost)?

And where this question began was reading a claim that carbon farming (i think it was mob grazing) could sequester all the carbon the rest of humanity had released into the atmosphere. And if this is true, it would mean there is a grave danger of overshooting the mark, in theory.  That grasslands left to their own devices would have gradually sucked all the last bits of carbon out of the atmosphere, leaving the planet cooled and lifeless.  Obviously nature hasnt done that, some homeostasis has maintained for the past several millennia.

So it had me wonder if there was another factor, and the greater quantity of fixed vs. atmospheric nitrogen because of the extreme amount of haber-boschery weve done affecting the land as a whole seems like a major factor.

Can anyone explain or put a link to an overview of how all this fits together, what proportions of impact each of these human factors has had?

Does it make sense to put some amount of industrial, haber-bosch process into carbon sequestration as a trasitional tactic to keep the atmoshere's balance at this sensitive time?

Does have any importance to our thinking/understanding today to recognize that some percentage of the nitrogen in yard waste or food scraps or urine etc we scavenge for our landscapes originated through human intervention vs. nature's activities?

(I had assumed before studying permaculture that all human impact was negative,  unbalancing, but is the total amount of plant life possible on Earth greater thanks to our fixing so much more nitrogen? Did we, unwittingly,  partly do a good thing for all life? How "full" was Earth's land and seas with life before haber-bosch? What are the biggest factors that differentiate desert/minimally life-supporting land from maximally life-supporting land?  Thanks!

I neglected to add --

Haber-Bosch process involves releasing a lot of CO2--but then that fixed nitrogen is "reusable", so we come out ahead, right?

I read that corn captures more carbon in its chemical process than other plants--seemingly much more per acre than trees in their first few years--might growing corn in deserts with no palatability or transportation requirements limiting things allow for some carbon sequestration benefits,  as a transitional, stop-gap measure?

I'm learning what the proportion of the major elements is in a plant.  CHON is the major elements of life, we learned in high school, however it is not like a plant is about one quarter nitrogen.  It's more like 5-10% maximum:

"These three elements [Caron Oxygen and Hydrogen] constitute 90 to 95% of the dry matter content of most plants." -- Clemson.edu

Organic matter is heterogeneous and very complex. Generally, organic matter, in terms of weight, is:[6]

45–55% carbon
35–45% oxygen
3–5% hydrogen
1–4% nitrogen

-- wikipedia, "Organic Matter"


(BTW--there's also the question of bioavailability of the nitrogen--plant matter isn't immediately bioavailable, microbes have to finish the transition, in two phases  The last phase takes 1-3 weeks;  the first phase can take longer (I didn't see how long in the article).)

157.3 million metric tons (t) -- haber-bosch process ammonia produced in 2010
451 million t of CO2 released -- haber-bosch process producing ammonia in 2010

So, if each of those 157 metric tons of nitrogen were 4% of a really really big tree, those 157 million / 4% = 3900 t of carbon they sequestered.  An eightfold increase over the amount of CO2 the haberbosching had released initially.

It seems from that angle as if the haber-bosch process ought to be contributing to a reduction of carbon in the atmosphere--whereas the ppm of carbon have been increasing.  Unless of course--and this is really my larger question--the carrying capacity of the earth for plant life has been reached or human activity has reduced it in net impact.  (Desertification, agribusinesses, clear-cutting?)

The missing piece is where that nitrogen goes--if we could handle our s--t (poop and pee) more constructively then perhaps that could help things a lot.

If we didn't overeat meat and have a lot of that nitrogen tied up in cows--and cycling through many more cows per acre per year than lived per acre per year in the past--we would have less of a problem.

If we didn't overflow nitrogen into oceans and cause massive algae blooms that then kill off local life, including plant-kingdom life I assume, disrupting effective carbon-capturing cycle ecosystems...

If we didn't have huge inefficient poop-processing plants that only generate a quarter of the energy needed to run them (even Bill Gates did better than that with the omniprocessor, it powers itself and generates some surplus electricity)...and releasing CO2 to compensate for the remaining 75% (Deer Island plant in Massachusetts).

There's tons of information here already. Here's something to think about. My brother-in-law has a permaculture and certified organic walnut orchard. He's been harvesting walnuts year after year after year. The walnuts-and the nitrogen contained in them-is shipped off the farm year after year after year. His soil test came back that his soil nitrogen is getting lower so he's starting to think about what he can do. Eventually it's going to reduce his walnut harvest or effect the health of the trees. Farming is not a natural process because in nature, crops aren't harvested and shipped way year after year after year. Other walnut farmers use chemical fertilizers but he doesn't want to this (nor can he as a certified organic producer). Other organic walnut farmers (and there aren't many), fertilize with things like chicken manure that they bring in outside the farm loop but he doesn't want to do this either because he wants to keep farm production based on the farm. He runs sheep on his farm already for part of the year but he was thinking of adding pastured chickens between the walnut trees for the added manure and nitrogen. (Animal manure is readily available as nitrogen to plants.) But adding pastured chickens that are eating dropped walnuts and orchard grass aren't adding anymore nitrogen than are already on the farm and when they are shipped to market as meat birds, he's actually losing even more nitrogen since the protein in their bodies is made of nitrogen. (Note, manure has nitrogen in it but animals don't "make" nitrogen. The nitrogen in their manure comes from the nitrogen, aka protein, in the food that they eat and is then concentrated in the manure.) And if he goes outside his farm loop and brings in chicken food, the chickens convert the nitrogen in the grain into a readily available and concentrated nitrogen but he's still losing at least some of the nitrogen when he ships the birds off the farm. And the chickens don't make nitrogen, they use nitrogen in their food, so he theoretically could just spread chicken food over his farm and as microorganisms eat the grain and decay, they'd add nitrogen to the soil. Not as efficient as chickens and costly, but you get the idea. The added nitrogen has to come from somewhere. You can read more if you look up stuff on the nitrogen cycle.

The primary way that nitrogen can be "manufactured" for his farm is by the bacteria that attaches itself to the roots of legumes. There's a mega-ton of nitrogen in the air but it's stable and plants can't access it from the air.  The two main ways to extract it are the Haber-Bosch method and by certain bacteria like those that fix themselves to the roots of legumes. So as an organic farmer, his best suggestion is to plant a lot of legume cover crops that will add nitrogen to replace the nitrogen lost when he sells his walnut crop each year. (I guess the ideal loop would be to add lots and lots of humamanure to close the walnut/walnut-eating-people loop but that's problematic in itself.)

So too much nitrogen might be a problem as you said but for farmers, too little nitrogen can be a problem too. I don't have the answer.

Thanks, that is a clarifying post to  bring it back to the individual farm and loops.  Yes, humanure is the closed loop, and yes it has problems but more from our societal choices than physical.  China required poop to be used for farms beginning in the 50s, and in an ideal world we would pay for food in excrement and labor in labor.

My real query is about the system as a whole planet.

Was the planet full/at carrying capacity before haber Bosch?  Do any trees' roots reach deeper or organic matter soil depths reach deeper or plants inhabit more land area than before? (It also needs to be measured in time as well--carbon per year in vs out--since cycling through faster doesn't change the net amount in the atmosphere.

Now I recalled at some point that the Earths atmosphere used to be all carbon dioxide millions of years ago, before plants evolved and began to transform it.  So that sequestration reduced from 1000,000 [one million) parts per million to 400 parts per million.  So millions of years did a bunch more than haber-Bosch has.  All that carbon had to go somewhere, much is in petroleum deposits now (old plants) and much in living and ded plants and the soils.

Yet there might be yet more places lacking nitrogen-fixers, either in the wild or on farms like the walnut farm mentioned. Or industrial ag farms.

I don't know my question now but my gut feeling is there's still something I haven't picked up on yet.

I realized another part of the problem--toxic inputs into nitrogen supply.  Chicken factories filled with antibiotics in the manure--you can't use that, can you? does it break down? what baout if the chicken feed contains persistent herbicides....  Human poop from ill humans taking antibiotics, eating veggies that have some herbicide content or meat or dairy with same.  

I don't know the quantities that would make this problematic...but if we're going with better-safe-than-sorry, this is a big energy loss, not just the nitrogen itself and its contained energy, but all the energy you'll now need to re-Haber-Bosch new factory chicken poop from factory chicken feed (agribusiness corn).  

Are these other kinds of exit points for nitrogen more of a factor than even nitrification (returning of nitrogen to hte atmosphere)?

What generally happens to chicken manure from a factory farm?

“On the positive side, I think that a multistep process that also includes composting at the end of the system could significantly reduce the levels of antibiotics. Our earlier studies on poultry litter demonstrated that up to 70 percent reduction in antibiotics called ionophores can be achieved after 150 days of composting. Testing this hypothesis on dairy farm manure is the next phase of our project, and we are seeing some positive results.” --article on manuremanager.com

anaerobic digesting and reverse osmosis filtration both failed to remove these antibiotics and even concentrated them more than in the fresh manure.

Adding in composting too of course would mean releasing a lot of the N back into gas form

Using stuff like this for carbon sequestering projects in current desert areas, rather than for food or fodder production, would be more valid (still better than leaching them into waterways).

I was so excited to find this thread as I am writing a permaculture bioremediation course and was just writing about nutrient cycles.  This is interesting perspective, an the first post on permies i have found to be questioning nitrogen fixers... way to be edgy, after all edge is where the most growth happens.  My research was actually about nitrous oxcide as a little examined greenhouse gas, i was under the impression that healthy soil full of life holds on to nutrients.  In a permculture  system you would be using the nitrogen fixers to draw down atmospheric nitrogen but in healthy soil it would not leach away downstream or get released through tilling.  This still seems like a better system than hauling it to the farm with fossil fuels.  Also most places you could collect Ag runoff are going to have a bunch more toxins with them such as heavy metals.  Now some would argue that a permaculture farm is the best place to put some trace toxins as they will break down faster in the healthy soils, that being said people don't seem to be volunteering for decentralized toxins on their farm.  

The difficult thing is that agriculture seems to be the great cycle disrupter being that making a living by selling produce ships nutrients away from the system, humanure is a great thing but only works closed loop if the farm is purely for subsistence.   Permaculture gets flake from critics about weather it can be "taken to scale"  and i think it is scale that may be the root of our problems, getting creative solution to fix the broken system will only work so long.  So much of this mindset comes from the agrarian state that turned the fertile crescent into a dessert long before Fritz Habor messed with the nitrogen cycle.  If nitrogen fixing trees are not a solution, and neither is driving it back upstream, than maybe the only solution is subsistence, localized close loop systems?  I

Slightly off topic. I care to disagree Megan. Nitrogen is taken away in the form of produce in ever increasing quantities into ever growing cities. Where the sewer system takes it all in. Civilized rich countries are composting it in giant plants. It's very rich in nitrogen, tomatoes are abundant, but it's full of chemical toxins and medicines and recreational drug components. In theory it could be taken out. It's just too expensive.

This is a cool thread. Lots to think about.

Off topic but one other thing about human feces besides antibiotics is hormones. Birth control pills, and hormones like estrogen and testosterone, are common. Humans can potentially have some pretty dangerous substances too. I once had a serious illness that involved a test with radioactive substances.

Hugo Morvan wrote:Slightly off topic. I care to disagree Megan. Nitrogen is taken away in the form of produce in ever increasing quantities into ever growing cities. Where the sewer system takes it all in. Civilized rich countries are composting it in giant plants. It's very rich in nitrogen, tomatoes are abundant, but it's full of chemical toxins and medicines and recreational drug components. In theory it could be taken out. It's just too expensive.

Thanks Hugo,
I actually don't think we disagree at all, I work with coming up with solutions to toxins for a living and the ethical questions around these issues keep me up at night.  I of course don't think that suggesting the world return to subsistence farming is going to work, and while idealism has many solutions, transition is the only path worth our time at the moment.  The disscusion on Humanure was about the closed loop system as far as nutrients and I was saying that subsistence closes the loop, again not practical but a necessary element to a nutrient cycle discussion.  
As far as the toxins in compost and human waste goes these are tough things to make ethical calls on, for importing toxins is never a fun idea and exporting them does not solve the problem, in fact exporting toxins has made a HUGE problem in the global south.  When it comes to heavy metals, is dilution the solution to pollution?    I digress this is a subject for different thread...
 
I am so glad permies is discussing this issue, nutrient cycles on a global scale is hard to wrap our heads around but critical for addressing the issues of agriculture and creating transition.  Composting on a municipal level is great and for every one to do this and bring it back to farms contains a carbon footprint as welll...  The more localized it all is the better...

(I suspect that I am about to spend the next two hours enjoying this thread)

too much nitrogen in our planet's ecosystem

By definition, I think it is probably the perfect amount.  But this thread seems to focus on nitrogen in our soil.  

By reading the first post, some of the general gobbledygook in my head, about nitrogen in soil is that it is quite temporary.   Further, in rich soil, high in OM, a lot of the nitrogen is bound up in living organisms.  And in soils with a lot of carbon, the addition of nitrogen gets "pinned" to the carbon to begin the breakdown process (nitrogen immobilization).  

As the organisms go about their day consuming and pooping, some of the nitrogen is released in various states - many of which are gaseous.  Some of it escapes (denitrification) and some of it is trapped for a bit and some of it is food for something else.  

Overall, rich soil and/or dirt with a lot of carbon mixed in, can hold more nitrogen for longer.   But neither can hold it for more than a few years without something adding it back in (plants, animals, or N-fixing bacteria (kind of an animal depending on your view, but I prefer to think of them as a component of "rich soil")).

Great points Paul, I think that most folks forget that just because a chemical test for ammonium and ammonia has been completed and shows less than the accepted? quantity of N in the soil sample that doesn't mean there isn't enough N available for plants to grow healthy.
The microbiome takes care of any shortages and they attempt to take care of any gluts of nutrients.

The main reason Gabe Brown can grow corn in soils that test at 10% N is because his soil microbiome is so healthy that any shortage of N,P or K will be taken care of via microbe respiration and consumption of nutrients.

There are bacteria that take Nitrogen from the air and utilize it for their needs, excesses are released back into the soil where the fungi and other bacteria make it available to the roots they are living in, and around.

The other thing I see many misunderstand is that the big three aren't all you need in soil, while it is true that most of the minerals and other nutrients are present in rocks and soils, not all places have all the same nutrients or minerals.
When we are doing an assay of our soil it is my opinion that we need to focus on the overall picture instead of picking just a few to focus on.
If soil science was to re-examine their methodology from the plant's point of view, they might change up how they run a soil sample, which would give the gardener/farmer a far more complete picture of what they have and how to improve the nutrient profile of their land for farming.

Redhawk

I'm still reading the article in question.   I think I am beginning to see the point of the subject line.   Not "too much nitrogen" but "too much of the wrong mix of nitrogens".   I still need to finish reading it - and then possibly re-read it.  

Bryant:  Yes!   Chemistry based ag has valueable information.  But they seem to focus a lot of that on "NPK".   And even when looking at "N" testing tends to look at just one or two flavors of N.  It can be of indicative value - especially to chem ag farmers and gardeners.   But in permaculture, it is a very tiny view.  I like the idea that we might, someday, focus more on the root exudates of neighboring plants than a handful of molecules with N in the soil.  

(digging ... digging ... digging ... here it is)

Here is a picture I look about a year ago.   I think this was october or november.   All of the other rhubarb plants had gone dormant for the year.  This is a pile of rock and sand.  A berm.   We through some alfalfa seed down and it seems to have taken.   The apple tree is a transplant and somebody with a giant truck ran it over.   Fred mended the poor tree with a piece of tape.  

Note the dark green color of the leaves in both the rhubarb and the apple tree.  

Zero irrigation.  

This is an example of the tap roots of the alfalfa finding hidden water and sharing it.   And the alfalfa, a nitrogen fixer, is sharing it's abundance of nitrogen.  

I suspect that if I bothered to test this sand and rocks, I would find that it has extremely low N according to soil tests.  I also expect that in ten years it would be fair to re-classify the sand as "soil" with a good 10% (or better) OM - although the rocks will be dominantly unchanged.  :)

That is a great photo Paul, it shows a sandy soil that is becoming filled with OM, the Lucerne (alfalfa) is doing what it does best, adding nutrients to the newly forming loam.
All those roots are holding onto bacteria and I'd bet that the roots will show mycorrhizae (at least arbuscular species) around the roots and spreading out into the forming loam.

Sand takes a while to change but the organic matter living in that sand is adding Om, building concretions and supporting fungal life all of which performs the task of building sand into loam.

Outstanding!

In time, I would like to see a dozen species all intermingled with the alfalfa, apple and rhubarb.   Each species contributing something amazing.  And I like to think that ten years from now we will talk about the flavor of the rhubarb (or apple) due to the neighbors.  

The moral of THIS nitrogen story is: root exudates have greater influence than soil chemistry.  

Permaculture.

I still haven't finished reading the article which seems to be mostly about acid rain and politics.  

But to get perspective, I came back to read the OP which says:

In fact, the only thing that releases the fixed nitrogen back into the atmosphere in any quantity, from what I can gather, is other microbes.  Fixed nitrogen stays fixed (solid).

By "solid" do you mean the nodules?  

I think it will constantly morph through many forms in active rich soil.  But it is possible to effectively mummify N (like when making beef jerky) and storing in a dry place.   You could lock up that N for decades in the right conditions.  

What might be a solid form of N in the soil that isn't getting into my brain?

As the article seems to talk about a lot of ways that "reactive nitrogen" can get into the atmosphere and cause problems, I think a lot about grass.   Green grass is loaded with N.   And, in time, it will become straw (yellow and dry).   I've always just pointed at this and said "denitrification!" (it just occurred to me that I should point with a stick and let people assume the stick is a wand).  I never thought to contemplate which forms of N were going into the atmosphere.  Perhaps the very kind that the article author is worried about?

It has been my experience that Nitrogen is more likely to go through many morphological forms than it is to become "locked up by nature".
One of the few items that can hold onto its nitrogen after death, black locust, eucalyptus, redwoods, cypress and other rot resistant woods, I laid out a log of black Locust about 25 years ago on my land that was in the city, it was still there in spite of the efforts from termites 15 years later.
It had started to show some deterioration from fungi but they (the mycelium) were having a hard time getting into the heart wood.
Then I met a man who used BL for his fence posts and he showed me some that had been in the ground for 25 years and they were not rotting but they did show signs of weathering.
I found out from him that 30 years was his average life span for BL fence posts.
He even showed me a destroyed wood chipper that he had used to grind up some BL branches, the hammers were worn out as if they had been pounding on rocks instead of wood fibers.

My own thought is that without a thriving microbiome, not much nitrogen would be usable by our plants, I've even poured ammonia on test areas of pasture where I know I have a thriving microbiome with no visible effect.
I've also got a test area that I can wipe out the microbiome and then rebuild it with known species of bacteria and fungi, this area, when made barren, didn't show any signs of nitrogen uptake by the plants just installed. (they started to show all the signs of Nitrogen defects within a week of going into that ground.

Nitrogen can be stores as ammonia compounds, nitrites and nitrates are the other "normal" "solid forms I've come across regularly when testing soils.
It will also be stored in animals as part of their proteins (soft tissues), fats and in bones and cartilage.

And, we shouldn't forget that plants and animals can get nitrogen from the air as part of the respiration processes.

paul wheaton wrote:As the article seems to talk about a lot of ways that "reactive nitrogen" can get into the atmosphere and cause problems, I think a lot about grass.   Green grass is loaded with N.   And, in time, it will become straw (yellow and dry).   I've always just pointed at this and said "denitrification!" (it just occurred to me that I should point with a stick and let people assume the stick is a wand).  I never thought to contemplate which forms of N were going into the atmosphere.  Perhaps the very kind that the article author is worried about?

Reading through this thread I got to this post and an idea just POPed into my head. Does the change from green to brown represent the nitrogen off gassing as the plant dies or does it represent the nitrogen being pumped back into the soil to feed the microbeastie amigos or (and this is the new thought) does it represent the nitrogen being moved from a mobile form into a more complex and stable protein?  Maybe some of our more knowledgeable chemistry friends have some thoughts?

Also, I don't think I saw it noted, but to the OPs concern about N-fixing plants contributing to excess N in the soil, my experience has been that clovers and such won't nodulate in soil that has sufficient nitrogen supplied to it. The best nodulation I ever got (dark red centers on nodules as big as a lentil!) was after adding nothing but some rock dusts and a bit of home made compost over the cover crop seeds in beds that I had been adding manure to at the end of each growing season. So I don't think you need to worry about the N fixers taking things overboard

Bryant RedHawk wrote:One of the few items that can hold onto its nitrogen after death, black locust, eucalyptus, redwoods, cypress and other rot resistant woods ...

I think that this would be a combination of a massive gob of carbon (trees are about 400 times more carbon than nitrogen) combined with something to prevent rot.  Black locust is, if I remember correctly, 4% fungicide - thus an amazing tool at preventing rot.

Even still, while technically an example of nitrogen in a solid form, i guess I was thinking that when talking about nitrogen in a solid form - that would last a very long time, I was trying to think of something that had a higher percentage of nitrogen.   My best guess was something along the lines of ambergris or woodrat amber.

Joshua Myrvaagnes wrote: If I am trying to err on the safe side of not to making more than my share of the amount of fixing of nitrogen, it makes sense to lean toward using the flows of food scraps local to me (i.e. within walking distance or biking.

I choose to minimize imports to my horticultural endeavors.   I am concerned about many things, but at the top of my list is persistent herbicides that can pass through an animal or even make it through a composting process.   But this is just the beginning of my concerns.  

I used to import a lot of materials and used those materials to grow a magnificent garden jungle.  And now I think back and cringe.  

Now, most of my effort is a lot like the alfalfa above:  yes, I did import that seed and the tree and the rhubarb culm.  But now I am using large plots of land and big gobs of time to replace all those imports.   I do confess that I have brought in some mulches - but they were through extensive analysis about possible issues of the material.

My path is most likely quite different from yours and maybe someday I will conclude that I was just being a nervous nelly.  For now, I would like to build a soil free of persistent herbicides and all the other things that worry me.

Joshua Myrvaagnes wrote: I think burying some food scraps in "worm towns" is appropriate and may put it in deeper soil where it is more inert.

Yay!  That's some poetry from my book!

Joshua Myrvaagnes wrote:I'm learning what the proportion of the major elements is in a plant.  CHON is the major elements of life, we learned in high school, however it is not like a plant is about one quarter nitrogen.  It's more like 5-10% maximum:

"These three elements [Caron Oxygen and Hydrogen] constitute 90 to 95% of the dry matter content of most plants." -- Clemson.edu

Organic matter is heterogeneous and very complex. Generally, organic matter, in terms of weight, is:[6]

45–55% carbon
35–45% oxygen
3–5% hydrogen
1–4% nitrogen

Here is the way I think of it.  

Good compost has a C:N ratio of 30:1.  

If something is stinky, it probably has a ratio closer to 10:1.  And the stink is denitrification.

And wood is about 400:1.  

If you put sawdust on something stinky, that denitrification from the stinky thing will go up to the sawdust and bond to the carbon to start doing something a bit like composting.  So the pile doesn't stink anymore (or stinks a lot less).

Dead people/animals stinks.   Poop stinks.   Rotting grass stinks.   Therefore, the C:N ratio is probably closer to 10:1.

Laurie Meyerpeter wrote: (I guess the ideal loop would be to add lots and lots of humamanure to close the walnut/walnut-eating-people loop but that's problematic in itself.)

Convert people urine to walnuts.

Convert people poop to willow trees and then use the willow trees as organic matter for the walnuts.

paul wheaton wrote:

Bryant RedHawk wrote:One of the few items that can hold onto its nitrogen after death, black locust, eucalyptus, redwoods, cypress and other rot resistant woods ...

I think that this would be a combination of a massive gob of carbon (trees are about 400 times more carbon than nitrogen) combined with something to prevent rot.  Black locust is, if I remember correctly, 4% fungicide - thus an amazing tool at preventing rot.

Even still, while technically an example of nitrogen in a solid form, i guess I was thinking that when talking about nitrogen in a solid form - that would last a very long time, I was trying to think of something that had a higher percentage of nitrogen.   My best guess was something along the lines of ambergris or woodrat amber.

Good points, I didn't even think along those lines. Perhaps I need to defocus and let my feeble mind wander more often.

Joshua Myrvaagnes wrote:I realized another part of the problem--toxic inputs into nitrogen supply.  Chicken factories filled with antibiotics in the manure--you can't use that, can you? does it break down? what baout if the chicken feed contains persistent herbicides....  Human poop from ill humans taking antibiotics, eating veggies that have some herbicide content or meat or dairy with same.

I wish ....  and I am allowed to wish for things ...   .... I wish for millions (or maybe billions) of small permaculture gardens with chickens, instead of chicken factories.  

In the meantime, your concerns are valid.   That manure is loaded with a lot of issues that would make it problematic for use in horticultural endeavors. Even if feeding that manure to grass/grain monocrops.

I often end up with small amounts of chemical fertilizer that is left behind when people move out of houses that I'm going to demolish.  If they contain herbicide, I take them to a recycling facility. If it's just an NPK mix, I broadcast it under hardwoods that are growing rapidly. Those nutrients will either become part of the tree or I'll get them back as leaf drop that won't be nearly so soluble.

I never buy the stuff, but since I have become the steward of it, something must be done. I think this is the lesser evil.

I've been studying soil and the Nitrogen cycle, as a Master Gardener, so that I am better able to advocate for soil care and regeneration.
My education was not science, so it has been and is a challenge for me to understand the chemistry.

Here is a link to several webinars posted by the Organic Farming Research Foundation, narrated by Dr Mark Shonbeck:
https://eorganic.org/node/27448
Dr Shonbeck has a wonderful ability to take these complex concepts and present them in a way that I can understand (or at least begin to understand) them.

I recommend scrolling down the page to "Soil Biology for the Western Region: Organic Practices to Recruit and Nurture Beneficial Biota in the Soil" and to "Breeding New Cultivars for Soil-enhancing Organic Cropping Systems in the Western Region".

Here's my primitive understanding of the N cycle in the soil:

Atmosphere is 78% N in the form of Nitrogen gas, N2. This is a very stable form of nitrogen, not easily transformed. Only lightening, certain nitrifying soil bacteria, and the Haber-Bosch process (which is very energy intensive, and polluting) can transform this form of N into plant available forms. Once in the soil, the N forms are more labile, or dynamic, and get taken up and transformed by the soil organisms, and plant roots. Soil fauna hold N in their bodies (immobilize) until their body is taken in by some other organism, which releases the N in its excretions to a plant available form (nitrate or ammonium). Anaerobic conditions are suitable for other bacteria to release it to the atmosphere as nitrous oxide, a potent greenhouse gas, several hundred times more potent than
CO2. There are also aerobic denitrifying bacteria that convert N back to the stable gas N2, and release it back into the atmosphere.

Excess nitrogen is either released back into the atmosphere or leached through the groundwater, which leads to dead zones in our waterways. About 50% of agriculturally applied N is wasted in the US, which means it becomes a pollutant. Synthetic N is bad news for soil biology and our atmosphere and hydrosphere. It tends to create acidic soil conditions, and what seems even worse to me, excess N in the soil causes the plant–microbe mutual relationship to diminish. Plants overfed N (and other nutrients) loose the ability to partner with beneficial microbes (including fungi) in the soil.

In the webinar about breeding cultivars for organic production, Dr Shonbeck explains this.

Here's another article which is part 1 of 2 on explaining the N cycle, part 2 describes the human impact on disrupting the N cycle.
https://climateandcapitalism.com/2019/04/18/nitrogen-crisis-a-neglected-threat-earths-life-support-systems/

D payne wrote:
Here's another article which is part 1 of 2 on explaining the N cycle, part 2 describes the human impact on disrupting the N cycle.
https://climateandcapitalism.com/2019/04/18/nitrogen-crisis-a-neglected-threat-earths-life-support-systems/

Thanks for linking to that article.
I have seen the very same graphic on Planetary Boundaries in a lecture held by one of the most important enthomologists (i.e. studying insects) of Germany two weeks ago.

While global warming is a big threat that is taking big attention (good thing), the loss of biodiversity and rise in atmospheric nitrogen are putting us in an even more critical situation. The loss of wildlife (insects, birds) is dramatic in Germany (some species over 87% in the last 19 years), and as far as I can see all over the world.

The concerning issue is that not only the known factors like herbicides, pesticides, loss of uncultivated land etc. can be held responsible, but the drastic increase in air-borne nitrogen destroys even those habitats (e.g. Nature reserves, far away in some valleys of the Alps etc.) that are never sprayed.
Many of those habitats with their specific flora is dependent on POOR soils. Plant and insect diversity is far higher on meager soils. And for those plants that can absorb higher amounts of N like stinging nettles, those plants might thrive with the overflow of N from the fields nearby but the caterpillars of some specialized butterflies drop off dead from those "overfed" plants.
That was something new and shocking to learn for me.
While I understand that N complexes in the atmosphere are difficult to measure he mentioned a number that was drastic. Unfortunately I have a very bad memory for numbers, but it was probably 30 times the amount we had in pre-industrial times.

As gardeners we tend to rejoice when we have rich soils, lush green vegetation.
But as Paul Wheaton wrote in his post: "I used to import a lot of materials and used those materials to grow a magnificent garden jungle.  And now I think back and cringe."
So we have to rethink about loops.

But I fear change is slow to come. I know bright people who more or less want to live a sustainable life, but coming from farms and having studied Agronomy they still talk about the holy NKP triangle and won't hear of microbioms helping to make airborne N available to plants.
They say it is just simple math: test the soil, see how much N is missing, dump the missing amount on the field, over.

In Germany we are having massive problems with overfertilized fields leaking N complexes into the waters. In 2016, the EU Comission sued Germany for keeping exceeding the permitted levels (https://www.euractiv.com/section/agriculture-food/news/eu-takes-germany-to-court-over-high-nitrate-levels/).
There are a lot of big scale feedlots concentrated on little land, and the liquid manure accumulating is a huge problem. Some of it even gets exported. Most the feed gets imported. A gigantic, screwed circle of N.
Even mid-scale dairy or pig farmers are obliged to have some acreage of fields (feed, grass, what, often corn for biogas) in order to be able to dump the manure!
In former times manure was seen as valuable addition to the soil (as it was part of a local loop), now it is a huge stinking burden that farmers need to get rid of.

Even here near my place where we don't have big ag we can smell all the farmers dumping manure before a rain is predicted as they may not dump the manure in a dry spell.
Two years ago there were very heavy rains in the north of Germany and fields got swampy and could not be worked with heavy machinery. So all those pig and dairy farmers were sitting on huge tanks of sh*t which were almost overflowing as they could not be disposed of as usually.

One of the reasons I buy my milk from a local farm where they have their own fodder mown from their own fields, and to buy all meat and dairy from organic certified farms only, even if many people I know shrug and say they would not waste the money as there can be no big difference, right?

Thanks everyone for posting.   I realize I misstated my original question.

Here's a rephrase: "is there a danger of having too much fixed nitrogen on our planet in total?"  Just as we (mostly) all agree we don't want too much total carbon (CO2) in our atmosphere, could there be a point past which we fixed too much nitrogen?

And the answer I'm at currently is no‐-nitrification(release of fixed N into atmospheric) happens even without a plant, by simple burning up of an energy.  The fixed N itself has more energy than "loose".  Something (some abundant microbe) is bound to come along and feed on that free energy supply and reduce it.  It's easier to get scavenged by a microbe that releases it than by a plant (complex, multicellular, sun-dependent and water-dependent, etc.)

Then a bunch of other questions emerged from the line of inquiry.

I'm still intrigued by the idea that "the problem is the solution " in terms of industrial ag corn or grasses production and N recycling from toxin-riddled favtory chicken manure as a stopgap measure for sequestering carbon.  And this notion of nitrogen changing forms in the soil so much, and being more or less bioavailable based on companions and microbes nearby.

I'm still wondering about the situation we inherit today in the wake of Haber-bosch. What is the net impact on the planet's ecosystem as a whole??

Anita Martini wrote:

D payne wrote:
Here's another article which is part 1 of 2 on explaining the N cycle, part 2 describes the human impact on disrupting the N cycle.
https://climateandcapitalism.com/2019/04/18/nitrogen-crisis-a-neglected-threat-earths-life-support-systems/

Thanks for linking to that article.
I have seen the very same graphic on Planetary Boundaries in a lecture held by one of the most important enthomologists (i.e. studying insects) of Germany two weeks ago.

While global warming is a big threat that is taking big attention (good thing), the loss of biodiversity and rise in atmospheric nitrogen are putting us in an even more critical situation. The loss of wildlife (insects, birds) is dramatic in Germany (some species over 87% in the last 19 years), and as far as I can see all over the world.

The concerning issue is that not only the known factors like herbicides, pesticides, loss of uncultivated land etc. can be held responsible, but the drastic increase in air-borne nitrogen destroys even those habitats (e.g. Nature reserves, far away in some valleys of the Alps etc.) that are never sprayed.
Many of those habitats with their specific flora is dependent on POOR soils. Plant and insect diversity is far higher on meager soils. And for those plants that can absorb higher amounts of N like stinging nettles, those plants might thrive with the overflow of N from the fields nearby but the caterpillars of some specialized butterflies drop off dead from those "overfed" plants.
That was something new and shocking to learn for me.
While I understand that N complexes in the atmosphere are difficult to measure he mentioned a number that was drastic. Unfortunately I have a very bad memory for numbers, but it was probably 30 times the amount we had in pre-industrial times.

As gardeners we tend to rejoice when we have rich soils, lush green vegetation.
But as Paul Wheaton wrote in his post: "I used to import a lot of materials and used those materials to grow a magnificent garden jungle.  And now I think back and cringe."
So we have to rethink about loops.

But I fear change is slow to come. I know bright people who more or less want to live a sustainable life, but coming from farms and having studied Agronomy they still talk about the holy NKP triangle and won't hear of microbioms helping to make airborne N available to plants.
They say it is just simple math: test the soil, see how much N is missing, dump the missing amount on the field, over.

In Germany we are having massive problems with overfertilized fields leaking N complexes into the waters. In 2016, the EU Comission sued Germany for keeping exceeding the permitted levels (https://www.euractiv.com/section/agriculture-food/news/eu-takes-germany-to-court-over-high-nitrate-levels/).
There are a lot of big scale feedlots concentrated on little land, and the liquid manure accumulating is a huge problem. Some of it even gets exported. Most the feed gets imported. A gigantic, screwed circle of N.
Even mid-scale dairy or pig farmers are obliged to have some acreage of fields (feed, grass, what, often corn for biogas) in order to be able to dump the manure!
In former times manure was seen as valuable addition to the soil (as it was part of a local loop), now it is a huge stinking burden that farmers need to get rid of.

Even here near my place where we don't have big ag we can smell all the farmers dumping manure before a rain is predicted as they may not dump the manure in a dry spell.
Two years ago there were very heavy rains in the north of Germany and fields got swampy and could not be worked with heavy machinery. So all those pig and dairy farmers were sitting on huge tanks of sh*t which were almost overflowing as they could not be disposed of as usually.

One of the reasons I buy my milk from a local farm where they have their own fodder mown from their own fields, and to buy all meat and dairy from organic certified farms only, even if many people I know shrug and say they would not waste the money as there can be no big difference, right?

Wow!  I didn't even think of "atmospheric " fixed nitrogen--i assume you mean fixed nitrogen dissolved in rain?  Ben Falk mentions "fertigation" from rains.  I didn't even think that might have been changed by human impact.