
Soil Erosion: Why soil is disappearing from farms - joeyespo
http://www.bbc.com/future/bespoke/follow-the-food/why-soil-is-disappearing-from-farms/
======
Merrill
Even if wind and water erosion were eliminated, modern agriculture is
fundamentally a form of mining.

Farmers grow crops that remove nitrogen, phosphorous, potassium and a variety
of other minerals from the soil. The crops are shipped to cities typically
located on rivers or oceans. The crops are processed, eaten and the nitrogen,
phosphorous, potassium and other minerals are flushed into the rivers and
oceans.

The elements can be replaced as long as supplies of natural gas to fix
atmospheric nitrogen and reserves of potash and phosphate rock last. But it is
ultimately unsustainable.

~~~
PopeDotNinja
Recently I learned how much we depend on phosphate mining to provide nutrients
for farming, and I found it unsettling how uncommon phosphate deposits are.
Here's an entertaining sub-4 minute watch on the topic of how a majority of
phosphate deposits are located in Morocco --
[https://youtu.be/O0BooiAxQyY](https://youtu.be/O0BooiAxQyY).

I just looked up how much different countries produce, and had assumed most
phosphates would be coming out of Morocco. My guess was incorrect. It appears
that Morocco produces ~13% of the world supply, but has ~72% of deposits. For
constrast, the USA produces ~12% annually with ~2% of world deposits, and
China produces ~45% annually with ~5% of all deposits. If I were the leader of
a country with lots o' people, I'd be cozing up to Morocco a whole bunch. [1]

Knowing nothing about mining anything darn thing, I now wonder how interesting
the work is in finding & mining new sources sources of phosphates.

[1]
[https://en.wikipedia.org/wiki/Phosphate#Occurrence_and_minin...](https://en.wikipedia.org/wiki/Phosphate#Occurrence_and_mining)

~~~
emj
It's a bit worrying that they talk about burning human shit to get phosphate
when you can just compost it.

~~~
robocat
The issue is probably all the contaminants in human poo, especially medical:
anti-bacterials, hormones, radioactive tracers. Maybe it isn't so much
purifying the phosphate that matters, but removing components that would be
bad to recirculate into our food chain.

~~~
emj
High temperature composting deal with the most common problems anyways, and
you preserve the nutrients rather than burn them up. The biggest problem is
how bad water waste management systems are at producing fertiziler, the wide
spread idea that it's ok to pollute our waste water with what ever, making it
unusable for composte is not healthy. I do not think burning it can solve more
than a tiny part of that problem.

------
rmason
As a former agronomist there are a couple of things in this article that
concern me. It reads like a scare piece. Farmers for over fifty years have
recognized the problem of soil erosion and are moving to reduce tillage.

Sadly no-till where farmers plant into last years crop is only mentioned once.
No-till requires more management and adoption started slowly. But now better
chemicals for weed control, better planting equipment and adoption of a best
practices list has contributed to its successful adoption and it's popularity
has exploded.

I am skeptical of the discussion of soil microbes which previously have been
looked at as snake oil cures promising much but delivering little. There may
be a genuine breakthrough this time, but show this skeptic the university
replicated and peer reviewed research first. Far too often with these products
all you see are farmer testimonials which unaccompanied by university research
are a flashing red light indicating a scam.

~~~
strainer
Here is a recent overview from Washington State University "Soil biology and
soil organic matter; What do recent discoveries mean for soil management?"[1]
I copy one quarter of its provided references below here, just to illustrate
the situation that there is really no paucity of peer reviewed work from this
field.

About the potential for reversing the long term trend in soil degradation
through microbially 'un-interested' and herbicide assisted no-till methods -
wouldn't be appropriate to provide university replicated peer reviewed
research which substantiates _they_ have the situation covered ?

[1] [http://csanr.wsu.edu/soil-biology-and-soil-organic-
matter/](http://csanr.wsu.edu/soil-biology-and-soil-organic-matter/)

1/4 References:

Jackson, R.B., K. Lajtha, S.E. Crow, G. Hugelius, M.G. Kramer, et al. 2017.
The Ecology of Soil Carbon: Pools, Vulnerabilities, and Biotic and Abiotic
Controls. Annu. Rev. Ecol. Evol. Syst. 48(1): 419–445. doi: 10.1146/annurev-
ecolsys-112414-054234.

Janzen, H.H. 2006. The soil carbon dilemma: Shall we hoard it or use it? Soil
Biology and Biochemistry 38(3): 419–424. doi: 10.1016/j.soilbio.2005.10.008.

Kallenbach, C.M., S.D. Frey, and A.S. Grandy. 2016. Direct evidence for
microbial-derived soil organic matter formation and its ecophysiological
controls. Nature Communications 7: 13630. doi: 10.1038/ncomms13630.

Kästner, M., and A. Miltner. 2018. SOM and Microbes—What Is Left From
Microbial Life. In: Garcia, C., Nannipieri, P., and Hernandez, T., editors,
The Future of Soil Carbon. Academic Press. p. 125–163

Woolf, D., and J. Lehmann. 2019. Microbial models with minimal mineral
protection can explain long-term soil organic carbon persistence. Scientific
Reports 9(1): 6522. doi: 10.1038/s41598-019-43026-8.

~~~
rmason
Thanks for posting this research. It does a nice job of explaining stuff that
has been observed for a long time but which there was no explanation. Another
reason why it's worth my time to be involved with the HN community!

~~~
strainer
Me too, thanks for regarding. On second look, it's a better article than I
deserved to hit on - just quickly plucked from WSU since i've been impressed
there before :)

------
jillesvangurp
Soil erosion is a reversible process but it will require a little effort and
planning. When it works it's an investment that actually pays off.

Here's a nice example of the Chinese restoring some soil:
[https://rethink.earth/turning-desert-to-fertile-farmland-
on-...](https://rethink.earth/turning-desert-to-fertile-farmland-on-the-loess-
plateau/)

I've seen a documentary with some before and after video footage. Quite
amazing difference:
[https://www.youtube.com/watch?v=IDgDWbQtlKI](https://www.youtube.com/watch?v=IDgDWbQtlKI)

Planned grazing is another approach that has seen some success:
[https://www.theguardian.com/sustainable-
business/2014/aug/19...](https://www.theguardian.com/sustainable-
business/2014/aug/19/grazing-livestock-climate-change-george-monbiot-allan-
savory)

~~~
home_project123
Is soil erosion ever naturally reversed ?

It seems to me to be a one way downhill process ?

~~~
brohee
Obviously there was no soil at first since it's dead organic matter.

~~~
olliej
Yes, but that’s not “reversing” so much as completely rebuilding soil, which
takes decades of no farming and no tillage.

A lot of loss can also be trivially reduces by planting rows of trees between
fields, which I saw all over the place in NZ, but haven’t seen elsewhere.

~~~
brohee
Pretty standard in Europe :
[https://en.wikipedia.org/wiki/Bocage](https://en.wikipedia.org/wiki/Bocage)

------
29athrowaway
We produce food for humans, pets, livestock.

Most of the livestock is not necessary, and 30% of all food will be wasted.

Paper is also responsible for topsoil loss. Much of the paper is used in
advertising campaigns that receive little to no attention from consumers, or
to communicate information that could be sent electronically. Some more is
used in redundant forms of packaging.

We all have known how inefficient our processes are for a long time. But our
expectation is that the environment should adapt to our needs and not the
opposite. This belief is wrong, and will be proven wrong in the next decades.

------
gboss
I really enjoyed the book Third Plate by Dan Barber.
([https://www.amazon.com/Third-Plate-Field-Notes-
Future/dp/014...](https://www.amazon.com/Third-Plate-Field-Notes-
Future/dp/0143127152/ref=mp_s_a_1_1?keywords=the+third+plate+dan+barber&qid=1560270116&s=gateway&sprefix=Third+plate&sr=8-1))

While I don't know if the methods explored in the book will be able to sustain
the entire world population. I really liked how he argues in this century we
can focus on growing food for flavor and not just quantity and flavorful foods
generally come from farms that have bio dynamic practices which support soil
health and eliminate the need for nitrogen based fertilizers.

------
adrianN
One thing I'd love to see more studies about is adding charcoal to the soil.
There is decent evidence that this greatly improves soil quality as the large
surface area of the charcoal particles allows microbes to grow and stores
water. It also has the added benefit of capturing carbon in a form that is
stable for millennia.

~~~
jelliclesfarm
Bio char. But it works in more tropical areas. Otherwise it has to be shipped.
South America case studies plenty.

~~~
simonebrunozzi
I'm curious, why it doesn't work in temperate climates? Also, I think it
heavily depends on how "rich" / volcanic the soil is in the first place,
perhaps?

~~~
jelliclesfarm
[https://iopscience.iop.org/article/10.1088/1748-9326/aa67bd](https://iopscience.iop.org/article/10.1088/1748-9326/aa67bd)
: here

[..]Here we use a global-scale meta-analysis to show that biochar has, on
average, no effect on crop yield in temperate latitudes, yet elicits a 25%
average increase in yield in the tropics. In the tropics, biochar increased
yield through liming and fertilization, consistent with the low soil pH, low
fertility, and low fertilizer inputs typical of arable tropical soils. We also
found that, in tropical soils, high-nutrient biochar inputs stimulated yield
substantially more than low-nutrient biochar, further supporting the role of
nutrient fertilization in the observed yield stimulation. In contrast, arable
soils in temperate regions are moderate in pH, higher in fertility, and
generally receive higher fertilizer inputs, leaving little room for additional
benefits from biochar. Our findings demonstrate that the yield-stimulating
effects of biochar are not universal, but may especially benefit agriculture
in low-nutrient, acidic soils in the tropics. Biochar management in temperate
zones should focus on potential non-yield benefits such as lime and fertilizer
cost savings, greenhouse gas emissions control, and other ecosystem
services.[..]

~~~
nullstyle
That appears to be a limited meta-analysis that itself postulated the reason
temperate yield didn't improve because temperate soils were more fertilized on
average than the tropical soil studies.

We're talking in the context of soil depletion in this thread, so I don't
think their limited conclusion applies.

~~~
Nasrudith
One thing not mentioned often about rainforrests is that their soil is
actually pretty damn terrible. Which is also why you see things like
carnivorous plants there.

~~~
jelliclesfarm
So what if rainforest soil is terrible...their main function is to sequester
carbon and act as a carbon sink supporting habitat and balance terrestrial
ecology.

~~~
Nasrudith
That is more for "why it helps there in the first place" than any
disparagement of the rainforests. That the soil is terrible is more reason to
leave them there - especially when they provide steady rain.

It isn't like temperate climates where you can rotate between farms, fields,
and forrests over time easier.

~~~
jelliclesfarm
right. i hear you.

may i ask what you mean by 'terrible'...nutritionally deficient or acidic..etc
etc?

------
11235813213455
Tillage is killing organisms living in the soil, which are crucial for
fertility and resistance to erosion. Permacultures have interesting
techniques, like covering the soil to let weeds die and enrich the soil at the
same time, not sure how those techniques can scale, even if they are highly
productive. There are also the use of livestocks:
[https://www.ted.com/talks/allan_savory_how_to_green_the_worl...](https://www.ted.com/talks/allan_savory_how_to_green_the_world_s_deserts_and_reverse_climate_change?language=en)

other links:
[https://en.wikipedia.org/wiki/Topsoil#Erosion](https://en.wikipedia.org/wiki/Topsoil#Erosion)
[http://www.fao.org/3/a0100e/a0100e07.htm](http://www.fao.org/3/a0100e/a0100e07.htm)
[http://www.fao.org/3/t0389e/t0389e02.htm](http://www.fao.org/3/t0389e/t0389e02.htm)

------
pier25
Agriculture is one of the biggest environmental catastrophes humans have
perpetrated. Entire ecosystems have to be destroyed. I always find it
disturbing when vegetarians think eating plants is a peaceful affair.

One could argue about organic agriculture in balance with the environment,
unfortunately it produces on average 20% less than monoculture industrial
agriculture[1] and the food demands of the planet are only growing.

[1] [https://news.berkeley.edu/2014/12/09/organic-conventional-
fa...](https://news.berkeley.edu/2014/12/09/organic-conventional-farming-
yield-gap/)

------
sarego
What comes to mind is something called "zero budget farming" invented by in
India by Subhash Palekar. This is basically an approach based on the premise
that modern farming including Organic farming is killing the microbes and
other beneficial organisms in the soil critical to sustainable agriculture.
[http://www.palekarzerobudgetspiritualfarming.org/zbnf.aspx](http://www.palekarzerobudgetspiritualfarming.org/zbnf.aspx)

------
gdubs
One of the best books I’ve ever read on this subject is “Tree Crops”, Smith,
1929. Soil erosion is his main focus and he quotes FDR who says that a nation
that destroys its soil destroys itself.

The subtitle of the book, A Permanent Agriculture, inspired Permaculture — a
niche but growing group of farmers who look towards perennial crops with their
deep root systems, and less fickle needs for inputs and maintenance. Because
these plants are permanent, tilling is all but eliminated.

The green revolution with its world-changing chemicals born out of the world
wars led to a boom in yields, and has fed the world for the past century. But
with our changing climate, and the obvious destructiveness of industrial
farming (runoff, land use change and deforestation, emissions from tilling,
emissions from chemical production and transportation), it’s pretty clear we
need a new model.

If you look at my post history, I recently linked to The Carbon Farming
Solution — it’s fascinating and phenomenally well sourced. There’s an active
push to develop perennials to replace many of our staple crops. This is, er,
fertile ground for research.

------
0xDEFC0DE
Guess it's time to check in with the hydroponics scene and see how things are
coming along.

------
the_mitsuhiko
Farmers in Austria (where glyphosate was recently banned) are worried that
without glyphosate erosion will accelerate due to the lack of reasonable
chemical alternatives. This will be interesting to see unfold.

~~~
jelliclesfarm
No/minimal till regenerative Ag would work.

We have to change design of farm Mach aka tractors. Good opportunity for
automation in Ag to step up to the plate and create a new paradigm shift

~~~
Nasrudith
Glyphosate is no till farming already and keeps the soil in place with the
dead weed while it decays.

Farmers aren't paying money to spray it for shits and giggles.

Although it would be interesting to see both a robotic mechanical weed
killer's operation, performance, and economics in comparison.

~~~
jelliclesfarm
Ok. Minimal or No till/non chemical farming then.

There is no need for chemical Ag if we have automation. Chemistry removed the
need for hard labour. It is still possible to use mechanization to replace
toxic chemicals because weeding is all about timing, but even with
mechanization, labour costs add up. Automation is the solution. And we have
the capability and tech to do it now.

I suspect that there will be some resistance and possibly nascent tech will be
bought out to die in a dark vault after being acquired by the big players
whose market share will be threatened. But it’s only a matter of time when the
transition from tractor to Ag bots happens seamlessly..I feel the big tractor
companies are just trying to time and manage the transition. They certain have
a massive market share. Chemical Ag is certainly out. Automation will be the
new paradigm.

------
learnfromstory
Isn't there something extremely wrong about the math in this blerg? Surely 12
million hectares produces a lot more than 20 tonnes of grain annually. Did
they mean 20 tonnes _per hectare_? Otherwise it's low by a factor of ten
million. Either way doesn't make sense.

~~~
lsb
[https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/16/nrcs143_...](https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/16/nrcs143_014887.pdf)

[https://en.wikipedia.org/wiki/Bushel#Weight](https://en.wikipedia.org/wiki/Bushel#Weight)

A hectare is ~2 ac.

Wheat looks like 2-5 tonnes/hectare

Looks like 20 tons per hectare is pretty high, but

~~~
hjalle
It's 20 million tonnes per year according to the source
[https://www.unccd.int/actions/united-nations-decade-
deserts-...](https://www.unccd.int/actions/united-nations-decade-
deserts-2010-2020-and-fight-against-desertification)

------
throwaway3627
Dirt-based farms are antiquated and inefficiently use resources compared to
fogbox and airponics. Healthy soil is great, if it's for grassland vegetation
browsed by managed mega-herds.. otherwise, the trend (climate change and lack
of roaming mega-herds) is towards desertification.

------
winchling
I presume they will, but will modern greenhousing and 3D farming (under
artificial light in factories) help to reduce soil erosion, or not?

~~~
saalweachter
Scale is the problem.

Just constraining yourself to the US and using the arbitrary 2000 calories per
day per person, the US needs to produce about 2.4 x 10^14 food calories per
year. I'll leave it as an exercise to the reader to figure out how many
greenhouses that is or how many 3d hydroponic farms, but the counter offer is
a few thousand square miles of corn.

------
leakybit
Sounds like a good use case for GMO.

------
jelliclesfarm
Tillage.

------
graeme
I never make this kind of comment, but that was unreadable. It broke scroll
speed, didn't have a reader view, and the text constantly shifted from left to
right hand side of the screen.

~~~
zeristor
Looking at it on an iPad it insisted I go from landscape to portrait, a tad
impertinent.

~~~
stkdump
Same for my Surface clone, I had to detach the keyboard and rotate to
portrait. I ended up reading it in firefox reader view.

------
QuickToBan
With regard to fixing this, the article contains a link to:

[https://theconversation.com/to-restore-our-soils-feed-the-
mi...](https://theconversation.com/to-restore-our-soils-feed-the-
microbes-79616)

"To restore our soils, feed the microbes" (2017)

------
carapace
Agriculture is pretty much the dumbest thing you can do to land (other than
simply poisoning it.) It's a process of converting ecosystems into people
(and, since the invention of artificial nitrogen fertilizer, converting _oil_
into people.)

Ecosystems are more productive, so if we imitate Nature with "applied ecology"
(such as Permaculture), we can actually create a new kind of civilization. One
that _generates_ more healthy soil than it loses.

Toby Hemenway (RIP) gave a talk, "Redesigning Civilization -- with
Permaculture"

> Modern agriculture, industry and finance all extract more than they give
> back, and the Earth is starting to show the strain. How did we get in this
> mess and what can we do to help our culture get back on track? The
> ecological design approach known as permaculture offers powerful tools for
> the design of regenerative, fair ways to provide food, energy, livelihood,
> and other needs while letting humans share the planet with the rest of
> nature. This presentation will give you insight into why our culture has
> become fundamentally unsustainable, and offers ecologically based solutions
> that can help create a just and sustainable society. This is the sequel to
> Toby's popular talk, "How Permaculture Can Save Humanity and The Planet, but
> not Civilization."

[https://www.youtube.com/watch?v=H6b7zJ-
hx_c](https://www.youtube.com/watch?v=H6b7zJ-hx_c)

~~~
Nasrudith
That is nakedly not true at all for yields and shows a massive ignorance of
history, trophic layers, ecology, and economics to declare it less productive.
Less biodiversity by definition but that is essentially the whole point of
agriculture - producing what you want.

Permaculture really seems to be the new Lysenkoism. They keep on making grand
claims about their sustainability and output and how it is the only
sustainable way yet their yields aren't even any better than conventional
farming with crop rotation.

If you want to preserve nature your best bet is unsexy density - scales better
than local and distributed. Even solar and wind which benefit from being
spread around are still clustered.

~~~
carapace
You haven't had time to watch the video?

> Permaculture really seems to be the new Lysenkoism.

No need for insults.

> That is nakedly not true at all for yields and shows a massive ignorance of
> history, trophic layers, ecology, and economics to declare it less
> productive.

Yeah, I actually know a lot about this and you are just plain wrong.

Agriculture has always been destructive. The masses of people have
historically been miserable and malnourished, suffered from regular famines,
etc.

Applied ecology generates greater yields per acre, and per unit of labor
input, than any other system we have tried. It's a new form of civilization.

