Food Production, the Ecosystem, Diet, and Public Health I (Lawrence)

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Do curso por Johns Hopkins University

Introdução ao Hábitos Alimentares Americano: Uma Perspectiva de Saúde Pública

55 classificações

Johns Hopkins University

Introdução ao Hábitos Alimentares Americano: Uma Perspectiva de Saúde Pública

55 classificações

Explore how food intersects with public health and the environment as it moves from field to plate.

Na lição

Is Climate Change Vindicating Malthus? Food Security and the Right to Food

Welcome to our short course on the U.S. food system. In this first series of lectures, we dig into the very important concepts of food systems, food security and intergenerational equity and begin to explore what we eat, how that food is produced, and how our dietary choices impact our health and the health of the planet. This broad overview lecture lays the foundation for the rest of the course.

Food Production, the Ecosystem, Diet, and Public Health I (Lawrence)9:45

Food Production, the Ecosystem, Diet, and Public Health II (Lawrence)13:48

Food Production, the Ecosystem, Diet, and Public Health III (Lawrence)9:00

Conheça os instrutores

Keeve Nachman, PhD, MHS
Assistant Professor, Environmental Health Sciences
Bloomberg School of Public Health
Robert S. Lawrence, MD
Professor, Department of Environmental Health Sciences
Bloomberg School of Public Health
Pamela Rhubart Berg
Food Systems Education Program Manager
Johns Hopkins Center for a Livable Future, Department of Environmental Health and Engineering

Hello, this is Bob Lawrence.

We're going to now focus on some of the changes in

the food system in the late Anthropocene, and

look at the radical transformation of agriculture in the last 100 years.

This slide illustrates some of the many changes that have

accompanied the industrialization of agriculture.

The impact of human interference with the ecosystem, of course,

goes back to the very beginning of agriculture 10,000 years ago.

But it's really in the last century that we have greatly accelerated the impact

of our food production methods on the environment.

What do we mean by industrialization of food production?

It's a system for

agriculture based on the principles of the Industrial Revolution of the 19th century.

Mechanization, efficiency, speed, uniformity,

standardization, with an emphasis on increasing throughput.

In agriculture, we've seen a shift toward monocropping, meaning large acreage

planted in a single plant variety such as corn, soybeans, wheat, cotton.

The heavy use of inputs.

Fertilizers, pesticides, water, ground water with irrigation systems,

and a large reliance on fossil fuels.

The union of concerned scientists has defined industrial

agriculture as viewing the farm as a factory.

With input such as pesticides, feed, fertilizer and

fuel and outputs such as corn, chickens and so on.

The goal is to increase yield, measured by bushels per acre or

pounds of animal flesh for inputs of feed and decreased cost of production.

Usually by exploiting economies of scale and

externalizing costs to the environment.

By externalizing we mean not including in the retail cost of

a product the true cost of production.

So if there's great degradation of the environment, if you produce

an unhealthy diet that causes a lot of disease, and the consumers of that diet.

And those costs are borne by the healthcare system, or

by the public expenditures to deal with environmental degradation.

Those end up being externalized costs.

With the industrialization of our food, we have come to a food system that,

since the second World War, has relied heavily on fertilizer production.

We had a situation where in 1909 two German scientists Heber and

Bosh invented the procedure that allowed extraction of

atmospheric nitrogen and fixing it as ammonia.

The ingredient of nitrogen sources, nitrates for

both gun powder and for fertilizer.

Post World War II in the United States we had large munitions factories that

had been fixing large amounts of nitrate for use in our weapons,

and suddenly these plants were idle.

They were converted to production of synthetic fertilizers, and

the amount available at a very low cost to the American farmer escalated rapidly.

These conditions now allow us to

have heavy inputs without capturing those true costs.

High resource use of soils, water, energy.

The environmental consequences of degradation of our water systems,

pollution by pesticides and soil loss lead to the big dead zones in the Gulf

of Mexico,all the other attendant problems environmental degradation.

We have artificially inexpensive fuel, and

water and I say artificially because once again.

If you don't really account for the cost of exploitation,

if these externalized costs are not captured in the cost of

the product it appears as though indeed we can have our cake and eat it too.

Agricultural subsidies, the farm bill,

which had it's origins in 1933 at the depths of the depression and

served mainly to support farmers through the depression, to stabilize prices and

to assure adequate supply of food for the American people.

But in the early 1970's, when Earl Butts was the Secretary of Agriculture

a totally new approach to farm policy was introduced and farmers were encouraged to

plant hedge row to hedge row, fence row to fence row to maximize productivity.

Forget about stabilizing prices.

And rely on government financial incentives.

The USDA is caught in an awkward situation of having dueling roles.

On the one hand, its main purpose has been to promote U.S.

agricultural products, exports, and has been an important part

of minimizing our balance of trade deficit for the last 30 or 40 years.

Another section of the USDA is responsible for developing the recommended daily

allowances of foods for the American diet, and providing nutrition education.

And as we'll see later on, the policies that are promoted by these two branches of

the USDA are frequently at odds.

The transformation of American agriculture has been characterized by the decrease in

the number of farms, shown in that blue line that peaks at

about 1935, and the green line, which is the average size of the farm.

For many years, from about the time of the Civil War until post-World War II,

the average size of the American farm was around 160 to 170 acres, or a quarter

of a mile square section as the farm belt was developed during the 19th century.

Now we have increasing size of farm and decreasing number of farms.

This has led to overall little change in total land use for

agricultural purposes, but dramatic changes in rural communities.

With these mega farms, we have seen a hollowing out of many,

many rural communities.

Where the local seed store, the local mechanic, the local farm equipment

supplier, has gone out of business to be replaced by more remote sites for

large sales of farm equipment that sometimes exceeds $1 million in cost.

In addition to the change in the size of the farm

we've had a rather dramatic shift in the distribution of farms.

The top map here shows how poultry processing plants were

distributed in 1949.

And each of those little black dots represented a plant that

processed 50,000 or more chickens each year.

By 2007, each of these dots now represents a poultry

processing plant producing more than 1 million chickens per year.

And of the 8 billion, with a b, chickens that are raised in the United States each

year, that's about a million chickens every hour, 24/7, 52 weeks a year.

We've had tremendous consolidation of poultry production and poultry processing,

in what is now called the broiler belt, running from East Texas,

through the south, on up to the Delmarva Peninsula, in the Mid-Atlantic Coast.

The concentration of farms in larger and larger operations

distributed in narrower and narrower sections of the country has also been

accompanied by a shift from diverse and resilient to highly specialized.

The turn of the previous century, we had about five commodities per farm, so

you might have a small farm of 150 acres, where perhaps a flock

of 50 to 75 chickens, maybe a 20 or 30 pigs,

a couple of fields of alfalfa, some wheat, some sweet corn, all being produced at

a level sufficient to have at least five commodities available for commercial sale.

In the early 2000s we had shifted to the point where

now it's barely over one commodity per farm.

You might have a 2,000 acre farm in Southern Illinois or

Northern Iowa that is producing nothing but corn one season and

then soybeans the next in the typical corn-bean crop rotation.

With this specialization of course has come the loss of bio-diversity.

And increased vulnerability to extreme weather events.

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