Welcome back to the lesson on technological changes in

agriculture in relation to the change of the metabolic pattern of societies.

In this second session,

we will look at the technological lock-in of agriculture and, in particular,

we will look at the implication of an increase in

demographic pressure that's been taking place in the world and also,

the implication of an increase in bio-economic pressure that we

want to develop society richer and richer so they

have to allocate more and more a larger fraction of the workforce away from agriculture.

So first of all,

economic development implied a dramatic increase in the requirement of food products,

both because we have more people and because the people are eating more.

If you're looking at the history of humankind and looking at

the population - and the human population remained flat for the size of the population,

in fact, for a long period of time

and then the arable land per capita and the resources per capita,

of course, remained more or less abandoned

for a long period of time and the same in the food consumption.

Then suddenly something happened in relation to the industrial revolution.

The human populations are growing as a crazy and, of course,

the ecosystem resource per capita per person went down.

And then the food consumption per capita increased,

in spite of the fact that we had less and less land available.

Of course, this can only be explained by the fact that fossil energy entered into

the picture and then this provided the first driver of a change in agriculture;

we need to increase the yield per hectare.

Just to give you an idea,

not only did we have more people,

but people in developed countries eat much more than

the people in developing countries or in pre-industrial society.

In pre-industrial society, we can imagine the equivalent of 250 kilo grain per capita.

These are very, of course, a rough assessment,

but it's just order of magnitude difference here,

whereas in a developed country,

post-industrial country like United States,

you have a consumption that can be higher than 1,000 kilos per capita and

annual product with feedlot have a big part of this increase in consumption.

So there is another big change that happened with the developing of country,

that not only we had to produce much more per hectare,

but we had as well to produce much more per worker.

So again, this is something that we saw already,

the analysis of what happened in general in a country

given the dietary intake of a full year per hours available per person.

In a full year, 50 percent are lost for the [inaudible] population,

the active population work only for a small amount of time,

less than 2,000 hours per year - and then the other economic sector,

in general, take the large part of the workforce.

In the developed countries, you have,

in general, only three percent of the workforce in agriculture.

And this imply that the productivity of labor has to be very,

very high, because basically,

with 25 hours per capita - 48 depending in which country are you considering,

you have to produce all the food consumed in one year.

And this could be a pretty challenging task.

As a matter of fact, in a lot of countries,

we are using import to make up for the difference between what

can be produced internally and what is consumed.

Just to give an idea how the economics,

the level of economic development affect the workforce in agriculture,

you can see that this is the labor share of

the workforce in agriculture versus the GDP per capita.

And you can see that both the percent of

GDP in agriculture and the percent of workforce in

agriculture go down - dramatically shrinks - shrink when the GDP per capita increase.

There is no rich country that has

a large share of

its GDP from agriculture or has a large fraction of workers in agriculture.

So the agriculture becomes totally a marginal for each country.

In order to become developed,

an economy must get rid of its farmer.

So for instance, in the States,

all the food consumed per person,

which is quite a lot,

is produced with less than 20 hours of work per person in agriculture.

And what is impressive is that in agriculture of the United States,

export also a lot.

So probably, this is even less.

So then we can conclude that there are

two pressures driving the pattern of use of technical input in agriculture.

The demographic pressure, that is we want to

boost the productivity per hectare and reduce the requirement of agricultural land.

And such economic pressure that we want to boost the productivity per hour of

labor and then we have to reduce the number of farmers in the workforce.

Let's see now how this is achieved by using technology.

And again, this is achieved because of fossil energy.

This is - in agriculture is extremely clear.

This is a study that I did in 1992 when I

started to have this - to try to explore this link

- and this is a graph in which we have

how much land productivity will be required to be self-sufficient;

you know, how much food is eaten divided by the hectares available per capita.

And then this is the actual productivity of land.

Of course, the two are not to be exactly correlated because you can import and export,

but you can see that - more or less,

we can see that the more crowded countries have a larger productivity per hectare.

So then I did the same analysis later on to see whether things were changed.

As a matter of fact, it was a Ph.D. student of mine that did the analysis.

And then we got the result that basically things are exactly the same.

The more crowded country are producing

more per hectare and the less crowded country are producing less per hectare.

And then I did the same type of analysis,

this time for labor productivity.

So given the workforce in agriculture,

given the amount of food consumed by a country,

how much will be the productivity of labor required to be self-sufficient?

And then how much is the actual labor productivity?

Then again, you see that the correlation,

if possible, is even stronger.

You really see that the richer are the country,

the lower is the fraction of agricultural force

in the workforce than the higher is the productivity of labor.

Again, we updated the - let's see,

the analysis in 2003 and basically nothing changed.

The rich countries are reducing

their workforce in agriculture and then they are producing more per hour.

So basically, you have a substitution of farmers with

machines of more fossil energy and the poor country,

in general, don't do that.

What are they implications in terms of technical input?

Basically is that the crowded countries are using more irrigation than other countries.

This was in 1992 and then this is in 2003.

Of course, this is a study done in 2010, but, I mean,

you have a certain length of time to get the right data.

Then the fertilizer is exactly the same as irrigation.

This is a type of input that seems to be used more for boosting the yield.

Then this was 1992 analysis;

in 2003, is exactly the same.

Completely different is the situation for machinery.

Machinery is something that is just used to reduce the level demand.

So this is a classic of a rich country.

So this was in 1992 and now this is the situation in 2003.

So basically, we can say that the situation in agriculture,

the basic trend of - of technological progress

are pretty much locked in by these two pressure.

They are affecting what can be done in agriculture.

We have to produce more and more per

hectare due to the increase in demographic pressure and we

have to produce with less and less workers because of

the low economic productivity

of agriculture that we will have in other lesson on this;

that agriculture at the moment is not

economically competitive with the other sectors of the economy.

And then basically this results in

a continuous compression and reduction of the number of farmers in the sector.

In conclusion, we can say that this lock-in is very difficult to

be affected by policy

because there are very strong constraints coming from the social side.

We are becoming more and more an urban population,

so we are forcing agriculture to feed cities.

And then from the ecological side,

we are also getting problems with water and land

availability, protection of biodiversity.

And so this is a reason of serious concern for the future of agriculture.

Technological lock-in of agriculture

Sustainability of Social-Ecological Systems: the Nexus between Water, Energy and Food

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