Leaves Sequestering – Ecological and other dangers

The main purpose of this post is to answer a few concerns raised by people with an ecology background.

At the beginning, it is helpful to grasp that, in order to understand complex concepts, parallel thinking is necessary—or at least holding multiple concepts at the same time. Unfortunately, even with graphs and videos, that is not possible, so it is necessary to read a text a few times in full and learn its concepts. If it was a computer source code, we would need to test run the programme multiple times with different parameters, and the aggregated result of those runs would give an overall picture.

Regarding the main explanation of “Carbon Sequestration by Leaves and Dead Plants Carbonisation”, it is necessary to stress that the title is probably poorly chosen, but, again, expecting to gain all information only from the title would require making a title at least five pages long. Maybe a better approach would be to have something short like “Carbon Sequestration by biomaterial”, but that would be too ambiguous, implying that the master plan is to plant something.

The following are the necessary concepts:

  1. In order to understand the technique and everything meant there, you have to read all texts here:
    After reading those, there are few other things we have to bear in mind:
  2. 450ppmv CO2 in atmosphere is the generally-accepted concept for global warming as the point of no return. For those who don’t know, it is a point where nature on its own starts feeding CO2 emission by positive feedback; from there, no technology can help us go back. Simply put: we sealed our fate. Currently, we reached 410ppmv in May 2017, and, if we do not change anything drastically, we will get to 450ppmv in 10 to 12 years. Therefore, 10 years is our time constraint, unless we find clever ways to sequester carbon and extend that period a bit more, in order to fully switch to clean energy sources and find an answer for the meat and dairy industry.
  3. Methane from permafrost – the mentioned “450ppmv” number is not a switch: the point of no return will not happen exactly at that point, and some studies suggest those processes have already begun. They are already happening, and we do not know at what point everything will fall apart, reaching the point of no return. As a wide range of alarming parameters is already showing, all this can happen much sooner.
    Regarding CH4, there is 100 - 1000Gt of methane in the Siberian permafrost only, and 5Gt in the current atmosphere. Being 25-75 times more dangerous than CO2 as a greenhouse gas, releasing only 1% of methane deposits from the Siberian permafrost would mean doubling global warming potential. In gamer’s slang, that means “instant K.O.” and “game over”. We can’t grasp releasing more than that. Currently, even the most pessimistic global warming models do not account for methane—not because is not dangerous, but because no one can predict the consequences or dangers of such magnitude.
  4. Wildfires – The first time I wrote the main text, the number was around 4 million acres, but, as the year ends, we can roughly calculate that we lost 7 million acres (~2.8 million hectares) of forests due to wildfires. The estimation is made from available data, adding up only the most noticeable wildfire events, but the real number is probably much higher.
  5. Deforestation - To the above number we have to add lost forests due deforestation for industrial or agricultural purposes. In the year 2000, forest coverage was 4085 million hectares; in 2010, it was 4033 million hectares, with an annual loss of 5.2 million hectares per year.
  6. Tree sequestering rate – trees need at least 20 years to be fully grown, sequestering larger amounts of CO2. When trees are grown for industrial purposes, the forest is first densely seeded and then regularly thinned, in order to create more timber.
  7. Top soil (fertile land) loss - due to aggressive agricultural practices.
  8. Volcanoes and similar natural events (lowest point in Sun cycle) or any other event can act as lucky coincidences (“God’s hand”) that can temporarily help us reduce the temperature of the planet.
  9. Planet and nature - Whatever we do or do not do, the planet and nature will survive. So, it is not the planet that is in danger, but human civilisation is. The human time scale is small, with the best estimate around 100 thousand years. Nature has millions of years, and the planet billions of years, to play around; whatever catastrophe we make, life and nature will recover and continue as usual if not immediately then after few million years.
  10. Human population and rate of consumption – even if we solve global warming, even with 100% clean energy, there is a limit to how many people one planet can feed. It is true that we can stretch our production capability with better technology, but there will be the constant question of “who/what pays the price”, especially with the rate at which modern cultures consume.
  11. Business as usual (BAU) - even if we succeed with any (not just this one) sequestering technique, if we do not use that bought time to switch to clean energy sources, we will just end up in an even worse mess. In order to avoid potential issues, this technique is meant as temporary, limited to a maximum of 12 to 16 years of usage.

What are the dangers of the leaves sequestering method for forest ecosystems?
First, we need to mention a couple of things: in the described method, not all leaves are removed—not even all leaves from temperate forests are meant to be removed. This method is mainly meant for temperate forests (22% of all forests), and the suggested amount is 5GtC or 1/4 of leaves from temperate forests. With this important note, only the current year’s fallen leaves are removed, and only if they have not started decomposing or have not been covered with dirt. Last year’s mulch or newly-formed mulch is not useful for this method; only dry, fairly clean biomass that has not started decomposing is useful.

5GtC would be a theoretical maximum, but the fact is that, due to ‘time limit’, it is not possible to collect so many leaves. In the best case, from the time when the first leaves start falling to the first heavy rain or snow, considering latitude, there are between 30 to 60 days in the best case to carry out all the work. An additional obstacle is that most forests have bushes and grass on the ground, creating additional complications for collection. All combined, it would be great if, in such a short time, we could collect even 1GtC or 1/20 of all leaves from temperate forests.

It would be possible to collect/cut underlying biomass (grass, bushes, shrubs) shortly before leaves fall, in order to increase total biomass and simplify leaves collection.

In terms of scaling, we have not had projects of such magnitude ever before in such a short time. So, scaling would definitely create some challenges and create some limits, but this would also be an issue with any other method we try to apply. The problem is huge so it requires a solution of the same proportion.

Now, the question is whether the removal of leaves for 1 year in 20 years kills trees?
Are trees so sensitive that they cannot handle that loss?
What happens when leaves are blown by the wind?
How do trees survive in cities?
What happens with water retention?
How will removal of leaves impact the ground during the winter?
Even with the theoretical maximum, if we apply collecting leaves in stripes, where one stripe is collected every 4 years, while collecting a maximum of 4 times, what kind of impact would that have?
How big would be the impact on insects, other plants, fungus, and moss?
So, the question is: where do we find the other 4GtC?

In the text “Carbon Sequestration Beyond Tree Leaves”, I suggested many alternatives, but you have to remember that any alternative we choose will similarly deplete some soil somewhere else.

Does this method remove mulch removed ?
As I said, NO, it does not remove mulch. It does remove potential mulch-making material for 1 year, after which the spot is rested before the next collection occurs in 3 years. New mulch will be created during those 3 years before again removing dried, fallen leaves that did not start decomposing.
Mulch, especially the rotten and wet kind, is not useful. The collecting phase must happen before leaves start decomposing. Once decomposition is already in advanced stages of releasing CO2 and methane, it is too late.

What about last year’s mulch?
No. It would be hard to separate dirt and make it useful during the process of carbonisation; although it is theoretically possible, it would dramatically increase cost and create huge numbers of issues—equal as we would decide to separate and sort all chemical elements from one cubic meter of the ground.

Would taking leaves deplete trees and soil of all nutrients?
Leaves are full of nutrients, and there are 16 essential elements without which trees and other plants cannot survive. Leaves have significantly more nutrients than a tree trunk or branches: magnesium, calcium, potassium, phosphorus, sodium, manganese, nitrogen ... and many other micro elements have higher concentrations in leaves. Carbon concentration in a leaf accounts for 50 percent or a bit more.

Magnesium, for instance, is crucial for photosynthesis, and, after 40 years of aggressive agriculture, lack of it has becoming a big issue.

If leaf removal is done in a sensible manner, it would not deplete soil significantly, but we are far from a sensible species. We do not know how to limit our own growth or harmful economic practices, so there is a risk that things can get out of hand, if not done in a proper way.

As previously said, even at a rate 5GtC a year, or 4 times in 16 years from one spot, this would not have a huge impact on forests, and, at a collection rate of once in 20 years (imagine 20 stripes, where each year only one stripe can be collected), outcomes would be even less noticeable, but, again, we don’t really know, as no one has ever tried anything similar. Best thing would be to do a thorough study as soon as possible.

Logically, from real-world examples, we can deduct that trees will be fine, if we do it temporarily.

One example is leaf removal from cities, where trees still grow tall and old. Some say the reason for that is the city’s CO2, but CO2 was never an issue in the first place, as it is a very abundant element. Instead, it is the amount of other micro elements.

Next, just type in Google “lonely tree on mountain hill”, or, if you have ever been on a hiking tour, you will find many of such. Those lonely trees there are often very tall and very old, reaching the age of 300 years. Elevated CO2 does not exist there, and leaves are frequently blown far away from strong wind gusts, yet those trees still grow as usual. So, claiming that trees will fall if we remove one year’s worth of leaves is just plain wrong.

Forests have a complex biome and root systems capable of communicating and exchanging nutrients between trees, so, if we would remove leaves from a 10-meter wide strip, trees would simply exchange nutrients with nearby trees.

Regardless, a study should be done to assess the impact; maybe insects will migrate, and trees will exchange nutrients, but it would be good if we monitor this entire endeavour.

The nutrient issue is not limited only to leaf removal. Actually, it is an issue with any plant’s removal from its place of origin. In fact, my personal feeling is that any human who consumes food (eats) but says s/he is very concerned about leaf nutrients is hypocritical.
Why would I say such a thing?
It does not matter whether you are an ecologist or a vegan; it is the same.
Let’s think about food consumption for the chain of common plants, like tomato or potato. First, the fruit is grown in a certain area, then it travels hundreds (often thousands) of miles, and then it will end up in some megastore. Out of all food we produce, 35% will be discarded, never even getting a chance to be consumed, ending up in landfills. The rest will be eaten, digested, and—through the system of our guts and sewage disposal pipes—end up in landfills, rivers, or oceans. So, we are dumping all those essential elements into the oceans.
Basically, if you do not have your own garden with those plants, and you don’t fertilise them with night soil, just by eating, you are removing nutrients from the ground, dumping them somewhere else.
So, in a way, you, I and pretty much everyone else are responsible for topsoil loss (7). Therefore, it is hypocritical to say this method will make far more damage than we are already doing to agricultural land even without aggressive agricultural practices. The more the population grows (10) without a circular economy (which demands returning waste to its place of origin), this will continue to be an issue.

Although, something being hypocritical does not make it right or wrong, what I am trying to say is that, in order to fix the most pressing danger of climate change, we will need to do something fast, and it won’t be an easy task to find a method that is cheap or even profitable, completely non-harmful, and easy to scale. There are always pros and cons we will need to deal with.

Following the above logic, it seems that the most nutritious places are landfills, but there is a huge issue: we dumped mostly poisonous waste there, as well, so we cannot separate good things from bad.

Event that does not need to be all bad: we can look at this as an opportunity for a new project, something that will decompose waste and extract only things that plants need—maybe a plant, fungus, or moss that, when it grows, sucks all nutrients that can be harvested and composted, which can then be spread over the forest or agricultural soil as mulch, fertiliser, or an additional layer of top soil.

Or, maybe the issue of nutrition loss can be solved by a certain technological process during carbonisation. For instance: would it be possible to use deionised water to wash nutrients during the process of hydrothermal-carbonisation, then collect those essential elements and return them to the place of origin in the form of “mineral” water?

How about choosing plants or wood materials that are not so rich in microelements in the first place?
The entire idea to emphasise leaves or grass biomass is because of annual or shorter growth cycles, in contrast to trees that need 20 years to grow. As we only have 10 years to fix global warming, tree growing, cutting, and carbonisation is not a very good option. Maybe we could decrease growing time by using genetically modified, fast-growing trees, but that is always a risk.

The next thing we can do is branch pruning, a well-known technique for orchardmen, that will help trees to absorb light better, while giving us wooden biomass necessary for carbonisation and sequestering.

What about water retention?
Mulch is already doing that job, and we said we are not collecting mulch, especially not the last year's mulch that will do the job. Important things to bear in mind are seasons and location: we said that most important locations for this method are the forests of Siberia, Alaska, and Canada, with a small portion of temperate forests in the United States. In those places, temperatures are on average significantly lower than in California, for instance, meaning evaporation should not be an issue. During hot summer days and long droughts, leaves, bushes, and grass are gunpowder dry and equally flammable, which makes the spreading of wildfires easy and very difficult to contain. Collecting that material, and using material from nearby stripes to make watery mud, should be part of additional forest management, in order to prevent wildfires.
Otherwise, we will see more wildfires similar to those in California, which will rise further north with the increase of the temperature. Although wildfires can be good for the germination of many plants, in this case they are just adding to the global warming issue by increasing overall CO2 concentration and therefore temperature. Also, bear in mind that newly-grown plants are simply not capable of sequestering the same amount of CO2 as grown trees or even bushes lost in the wildfires.

Forest roads
There is a confusion about forest roads, and how would they look like. Forest roads does not mean highways or any kind of modern asphalt roads; forest roads are just simple dirt or, in the best case, gravel roads necessary for fire management and easier movement of machines we could use to collect leaves, grass, branches, or other bio material from forests. It is well known that forest roads could prevent the fast spreading of wildfires.

This year only, we lost more than 7 million acres of forests, and, while I am writing this, although it is December, wildfires are still burning, scorching huge areas in some parts of the world. If we prevented those and used that material to sequester CO2 by carbonisation, instead, that burnt area (if covered by an Oak forest) would give us 1 tonne per acre (or 7 million tonnes in total), just from leaves.

With temperature increase, the amount of wildfires will increase and move up north, while active desertification will start taking its role in climate change.

It is worth mentioning that, in regards to batteries, only 1 GtC of leaf carbon, even with a pessimistic calculation, would be enough to satisfy the planet’s need for battery energy storage. Usage of that storage would dramatically cut current waste in the electric grid and reduce overall fossil fuel consumption, consequently leading to less CO2 emission.

Although we could lock some portion of the atmospheric carbon in wooden products—paper, furniture, building material—that amount would be significantly smaller than the ~128 Giga tonnes of Carbon we have put in the atmosphere by burning fossil fuels created 65 million years ago.

Other products that can be created as a consequence of using this sequestering method are carbon for water filtration and charcoal we would bury underground to replace fossil fuels extracted from deep underground deposits, and these don’t require the same grade of carbon quality. They could be obtained from the wood material of fast-growing plants that don’t have a high content of essential elements. As our main goal is to lock atmospheric carbon, biomaterial necessary for carbonisation could be equally obtained from plants that can be grown by supplementing CO2 in indoor farms, in order to increase growth rate.

This sequestering technique is not meant to be used as the only method, and it is always meant to be used within previously explained rules. In order to get a clearer picture, we will need to carry out many future studies and calculations. If you have any further complaints, you are welcome to contribute by writing your own paper and suggesting solutions that could improve or even work far better than what was suggested.

The purpose of this mental exercise is to be a dialog starter. Instead of an attitude where someone says, “Ah, this method is stupid” and then ignores all other pros or cons, if you are really willing to help, and you have expertise in a field related to this project, the ability to discover issues is helpful, but more desirable is an ability to propose alternatives about how to make this happen—how to find fixes for things that do not pan out.

You are welcomed to join, but please be constructive and bear in mind all those above points, especially how little time we have left to actually do what is necessary.

Instead of being a person who only finds problems, can you be a solution-finding person?

While we are doing it, I hope you will at least take time to share these papers with others, so this idea could get more traction.