Put carbon where it belongs… back in the soil

We hear a lot about climate change
and carbon dioxide.

What can farmers do about it?

'A lot,' says Austra,lian soil scientist,
Dr. Christine Jones.

' and get better crops as a result.'

It's all about getting light energy,

transforming it to biochemical energy,

getting that biochemical energy
into the soil,

to drive the soil ecosystem
to make nutrients available

Well, the reason that carbon is important

is because all living things
contain carbon

so as things live and die,
they give up their carbon

and then something else lives
and takes up that carbon.

I guess what we're talking about
with climate changes,

we're talking about that cycle
getting out of balance

So, for thousands of years
it's been in balance...

the atmosphere and the plants,
and the soil,

and all the living creatures.

But in modern times people have dug up

and burned fossil fuels
and exposed soil for farming.

In fact, over a third of the carbon

added to the atmosphere since 1850

has come from deforestation

and exposing, and oxidizing
the rich carbon deposits in our topsoil.

U.S. soil scientist Dr. Elaine Ingham says,

'We can put it back though.'

'And in a way so that much of it will stay.'

So, carbon sequestration -
we're talking about putting CO2

from the atmosphere back into the soil

in a form that's not going to be lost.

How do we do this?

The same way nature did
in the first place.

We've got to be photosynthesizing.

So, we've got to be growing plants in that soil...

So CO2 and sunlight
will be bound back into sugar structures.

As those sugars go down
into the root system,

Picking up all the nitrogen phosphorus
sulfur magnesium calcium

from the soil.

Building that plant material -
the plants are putting

exudates out into the soil,

'cakes and cookies' out into the soil,

and the bacteria and fungi utilize that material

and build the organic matter
back in the soil once again.

Those sugar water exudates are the key.

This photo shows liquid carbon
flowing from a plant root above,

along a fungal hypha or two,

to feed the fungus below.

In exchange for that carbon,

soil microbes, including fungi,

bring water
or micro nutrients to the roots,

causing the plant to release more carbon.

In order to build that soil carbon,

you have to be looking after the microbial

or supporting
the microbial communities in the soil

that join all the little
carbon atoms together

to form humors polymers.

It can't grow as well unless
those microbes are there.

They won't have as many
trace elements in them

if those microbes aren't there,

and when the plants don't have
those trace elements in them,

they become vulnerable
to insect attack and fungal attack,

pathogens of all kinds.

Finally, we're now seeing
the light as it is

and realizing that we are like farmers.

And that what we need to do is

to harvest as much
sunlight energy as possible,

by having as much green leaf as possible.

Therefore, as much
of the year as possible.

Because photosynthesis drives
the whole system...

soil should always be covered with plants,

either crop plants or cover crops.

Farmers here in the United States

started experimenting with two-way covers,

and then five-way covers,
and then 10-way covers,

and now they're sort of aiming
for 20-way covers.

In other words, 20 different varieties
of plants in a cover crop.

And realizing that the more diverse
they make the cover crop,

the faster they can build soil.

And the more, less reliant
they are on any chemicals at all.

Farmers are finding
that building soil biodiversity

builds plant health.

And they're finding they don't have
to use any synthetic fertilizers anymore,

they don't have to use pesticides,

they don't have to use insecticides.

They not only are they producing food
that's higher in nutrients,

but it's also lower in toxic chemicals.

And they're taking co2
out of the atmosphere

and storing it in soils.

We also want resilience in our fields.

Carbon builds
a good clumpy soil structure,

holding on to rainwater.

And the other thing is how quickly
when the rain does absorb...

how quickly does it evaporate.

So when it gets into the soil,
we want it to stay there.

So we want to have
an aggregate send us all,

aggregates the little lumps
like pea show clumps in the soil

that have a much higher moisture content

on the inside of the aggregate
than on the outside.

And we see the greatest increases
in carbon sequestration,

through what I call
'the liquid carbon pathway' -

when it's being

fixed in and green leaves transfer

powder through the plants excuted by

roots into microbial communities in the

soil and forming aggregates and leading

to the process of unification which is

the holy grail for soil to have an

increase in humans in the soil so our

job as dr. Ingham says is to farm so we

are working with nature

so don't till could we have a list of

those farmers that are no-till or zero

till and really let people know that

they're the ones doing the work and as

dr. Jones says this kind of farming is a

win for everyone if we can take more of

the carbon that's in the atmosphere and

store it in our soil and our soils and

our food production systems are going to

be more resilient but we could produce

the same meal with much higher quality

with much lower cost and building soil

at the same time

I think the fundamental shift in

thinking that we have to make is that

farming is about harvesting light

through the process of photosynthesis

we're going to change light energy to

biochemical energy and then that

biochemical energy becomes our plants

our animals so you know through the

carbon compounds that are made by that

process we are fundamentally light

farmers and when we make that

realization then the sky's the limit.