This video is a collaboration with Fisheries and Oceans Canada and Ingenium.
Obviously, potatoes are the best vegetable — especially when paired with a
tasty campsite raclette.
But like all good things, obviously, the potato has its dark side.
"Die, potato!"
"Not today."
Do you know what a potato field
look? A potato field looks like this.
These images in particular are
of a field in Australia where I worked about 14 years ago. And personally,
when I worked in this field to transplant potatoes, I felt like I was in
a very natural place with fresh air, wallabies, and possums stealing
my cookies. And since then I have learned that this “natural” vision of agriculture, or at least of
intensive agriculture, blegh… it’s really not that natural. In order to maintain such
a high production rate, in general we use a lot of fertilizers, which can end up
hundreds or even thousands of kilometers away. In the oceans for example, with obviously
a pretty unpleasant impact on the environment. I know what you are going to tell me because it's
always the same refrain: as soon as we enjoy something really nice like a potato or a
raclette, there is always a issue on the environmental front. But where this is interesting,
is that this is one of the issues where it is possible to do better AND, as a bonus,
we even know how to do it! You guessed it, I am no longer in Australia, I am in Canada
where the potato is the most popular vegetable crop. And it so happens that in my garden, I have
some plans of potatoes, which will come in handy in this video. One of the common fertilizers we
use to cultivate potatoes is nitrogen. And for once, if there is one thing
which we do not lack, it's nitrogen. It makes up 78% of the atmosphere
(the N you see floating is the abbreviation for nitrogen). Except that the plant, in this case, has a small
quirk: it assimilates nitrogen much better if dissolved in water, in the form of
nitrate (NO3-) or ammonium (NH4+) ions. Look, some prefer poutine to raclette;
this plant prefers dissolved nitrogen to gaseous nitrogen from the atmosphere.
To each their own. And since it prefers it dissolved, that explains why we use fertilizers:
in order to give the plant this dissolved nitrogen. As for the potato
in particular, we're starting to know the plant pretty well, and it is estimated that 1 ton of
potatoes would need 3.7 kg of nitrogen for its normal development. In Quebec, each ton of
potatoes receives 5.8 kg of nitrogen, 1.5 times over what the plant needs.
So, as a small aside, plants did not wait for us to show up with our fertilizers,
in order to grow. All this diversity is not thanks to us. Well, maybe in a
Montreal park it is, but I mean in general. They do very well on their own.
In fact, with agriculture, we're actually breaking a natural cycle.
Because normally, the plant draws nutrients from the soil, and when it dies,
it breaks down, and the nutrients it absorbed return to the ground, and the
cycle starts over. With some losses here and there. But with agriculture, since
we pick the plant, its nutrients don't return to the soil, or at least
not as much as if we had left it there. So we break that cycle, and the field is gradually
impoverished from nutrients. Hence the need for fertilizers to compensate. End of the aside.
With fertilizers, we treat the plant like we would a cat that we're leaving alone for 4 days.
We know exactly how many kibbles he eats per day. But we still add in a few more
because “you never know”, in case the kitty cat would need to eat his feelings. And that
is the first problem: we're giving plants too much fertilizer. Then at some point,
rain will fall, and the rainwater washes the fields and carries the fertilizers
into the soil, and the nitrate concentration (it's nitrogen, remember) skyrockets.
Too much nitrogen in the soil, is our second domino. In Canada, the largest production of
potatoes is made in Prince Edward Island. And... I've never been. But I think I have a good
reason for not going. Oh, I'm exaggerating. An 11 hour and 28 minutes journey. That's
right next door!
Hey, there's a squirrel. Tshht! Tshht!
*anti-squirrel growl*
I don't like squirrels!
So if we combine the rain, the flow of water but also erosion,
it means that a karge amount of our fertilizers ends up in the ocean.
Now, it doesn't happen in a flash. It can take years for nutrients to
go from the potato field to the ocean, of course.
Ah, who caught the mismatch? I left without
my hat on and I'm coming back with it ;) Let's pretend that this is an ocean although it's
clearly just a pond. So, cool, we might think that all these extra nutrients landing in the oceans
will give a small boost to biodiversity.
... Nope.
It's a bit counter-intuitive, but for an estuary
or an ocean to be “well”, it actually needs to be poor in nutrients and when there are too many,
it unbalances the ecosystem. Seaweed proliferate, which prevent other organisms
living in the water to receive enough light — that's two dominoes at once. For instance,
you've probably seen this sort of thing before where there are long seaweeds in the water,
it's called eelgrass. And when you see these algae, it means that everything is fine,
BUT. If they begin to get covered over by the surface algae that you can see here… Houston,
we have a problem. These algae multiply at high speed and it can quickly look like
this. And I think we'd all agree that we don't feel like swimming anymore.
This uninviting seaweed is then broken down by bacteria which
consume a lot of oxygen, to the point where there will not be enough oxygen for the
other plants and animals to survive in this space. And if there isn't a lot
of movement in the water, then little by little, the whole area loses oxygen. And when the area has lost
its oxygen, the bacteria are replaced by other bacteria that are able to
further degrade matter without the need for oxygen. In the end, after all these steps,
only a few bacteria end up reigning their quiet little kingdom. And the waste of
this kingdom is, among other things, methane CH4. Methane, that greenhouse gas that is 34x
more powerful than CO2, so it contributes to global warming. And in the end,
in the kingdom of the few bacteria that live without oxygen, all the rest of the local biodiversity —
fish, microorganisms, everything — disappears due to lack of light and oxygen.
And all that is called the phenomenon of eutrophication.
We talked about the ocean,
because we followed the example of the potato field. But in reality, eutrophication due to human activity
is also found in lakes and rivers. Not far from Montreal, at
Gatineau Park, Pink Lake is in the process of eutrophication. The Wikipedia
article on eutrophication also shows how badly Europe is affected. Yet what
is crazy is that technically, eutrophication is not a terrible problem. It's a
natural phenomenon that is part of life and the evolution of lakes, oceans, etc. Except that
normally, it happens over several centuries, not a few decades. In fact,
the root of the problem is that our fertilizers accelerate the end of life of these bodies of water
much too quickly.
Let's not get depressed; there are solutions.
But these solutions must be
approached a little bit like a great fashion designer would a garment: tailor-
made rather than one-size-fits-all. We don't make a one size and unisex t-shirt
thinking it will fit everyone. Same thing for a potato field, for an estuary, for
a lake; you will need a specific solution for each. And then there are plenty of options,
actually. We could tackle each of the dominoes, quite simply. For example, if we look at the
very first domino, which corresponds to the fact that too much fertilizer ends up in the soil.
We could simply monitor what is in the soil with sensors and to only add
fertilizer when it is needed, where it is needed and in the amount it is needed. Like a smart kibble
distributor. We have the technology, we have the knowledge, we have the skills...
We just need to do it! Another option, we could also fertilize the soil naturally by rotating
different crops from season to season. For example, if we plant legumes,
these live in symbiosis with bacteria that live at root level
and transform the gaseous nitrogen into dissolved nitrogen. And as you know,
the plant loves dissolved nitrogen and therefore these bacteria serve it its nitrogen on a
silver platter — without impoverishing the soil. And if we leave the legumes in the field and
then bury them, they will decompose and fertilize the field. We will therefore need to add
less fertilizer when planting potatoes in their place. Although of course that comes with a
productivity problem, but that is another can of worms. We could also look into some
other dominoes. For example I think it was this one where the fertilizers ended up in
rivers. A very simple trick is to avoid planting potatoes in areas at risk of
flooding, or leaving buffer zones between fields and streams. Or this one,
where the algae proliferate: we can eliminate the algae before they die and have them
be broken down by bacteria, either tearing them off by hand or introducing
species that feed on it like some fish do. Which is still complicated because
you really have to be careful not to unbalance the ecosystem. This is probably the most complicated
solution to put in place, but it could be an option. Or this one, where the area gradually loses
oxygen: we can set up various mechanical water mixing systems,
with artificial fountains, so that the water can oxygenate better. The hard part is to
take the time, the energy and the funds to put the right solution in place. And that's where we
understand the importance of knowing and documenting a problem. Because when
we have all the dominoes in front of us, we can break this downward spiral. But of course, as always,
nothing in life is ever so simple. There isn't just one line of dominoes. In fact,
there are several lines, and they intersect with economic, social and
political considerations. We must ensure that in trying to break one line, we aren't
messing up another which would have been beneficial. Anyway, in this video I wanted
to tell you about three things. First, the chain of dominoes. It's hard to imagine
that because we put fertilizer here, the ocean that is over there is dying and
contributing to global warming. And that's why I wanted to talk about the chain.
It's hard to work against a problem when you can't see the whole chain. Hence the importance
of research, documenting problems, etc. The more we understand how a phenomenon occurs,
the better we will be able to stop it. Second thing, there are solutions. But we won't have
a one-size-fits-all solution for every field, every ocean, or every river.
And lastly, it will take time. Because even if we stopped using any fertilizer tomorrow,
a lot of it has already accumulated in the soil. These are very long-term solutions in
any case. Eutrophication doesn't have a one-size-fits-all solution. It's tailor-made.
But what wouldn't we do for potatoes and a good raclette?
Thanks to Fisheries and Oceans Canada and Ingenium for collaborating on this video. As a note, please
understand that we mostly talked about the potato because that is the most important vegetable crop here.
In truth, everything we have talked about applies to many other vegetables, but with their own nuances,
specificities… As you can imagine.
Bye!
{Bloopers — Mosquito Attack}