The Vicious Spiral and the CLF Concept Model I (Lawrence)

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Do curso por Johns Hopkins University

Introdução ao Hábitos Alimentares Americano: Uma Perspectiva de Saúde Pública

63 classificações

Johns Hopkins University

Introdução ao Hábitos Alimentares Americano: Uma Perspectiva de Saúde Pública

63 classificações

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

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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.

The Vicious Spiral and the CLF Concept Model I (Lawrence)9:59

The Vicious Spiral and the CLF Concept Model II (Lawrence)13:54

The Vicious Spiral and the CLF Concept Model III (Lawrence)7:45

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

[MUSIC]

My name is Bob Lawrence, and I'll be providing this introductory lecture and

setting the stage for following modules.

First, I want to say that the Center for Livable Future is based at the School of

Public Health, but it is a university center, and we work with many people from

different disciplines trying to pull together all the different important

strands that bear on food security, food production and public health.

The Vicious Spiral was a term introduced by the late Jim Grant.

Jim was the Director of UNICEF, the United Nations Children's Fund,

until his premature death in 1993.

He was a great advocate for children and for equity, and very concerned about

the fact that severe poverty was limiting opportunities for children worldwide.

He invoked the notion that poverty, population growth and

environmental degradation, created a viscous spiral that had to

be interrupted before we could really make progress, with child development and

indeed with overall economic development for the entire population.

Sustainable development is the progress for

all without exceeding planetary resources and the carrying capacity of the planet.

When the Center for a Livable Future was established in 1996,

we wanted to focus on the fact that we have had, in public health,

strong contributions to diet for virtually the entire last century.

One of the very first faculty members in the School of Public Health, was E.V.

McCollum, who had discovered both vitamins A and D, and from 1916 on,

was the first real nutritionist in the faculty of the school.

Similarly, we've had a very strong department of environmental heath

sciences for many decades.

Neglected, however, with the transformation of American agriculture,

was the overall impact of the food production system,

on both the quality of the diet available to the American people and

the impact of that food production on the environment.

So as this concept model shows,

food production influences diet in terms of the quality of the inputs.

Similarly the production of the food system with the generation of large

amounts of waste, excess nutrients, air water and

soil pollution profoundly influences the ecosystem.

These changes in our ecosystem and

in the diet have profound influences on the health of the public.

We also have ongoing pressures of population growth,

climate disruption, lack of equity in the distribution of food,

and resource depletion of non-renewables.

Looking at a global perspective on the problem of feeding the world,

we see that there are a large, large number of people who are subsisting,

barely subsisting, on less than a $1.25 a day.

They're concentrated in sub-Saharan Africa and in southern Asia.

If you look at the light blue bar, I chose the status of poverty in 1990.

The dark blue bar, 2005, and the millennium targets for

2015, are the yellow lines embedded in the dark blue bar on the bottom.

I have to draw your attention to the fact that it looks as

though Sub-Saharan Africa has the largest number of people living in poverty.

They have the largest proportion of their population living in poverty, but for

sheer numbers, India with its current population of almost 1.4 billion people,

in fact has more than 50% of all people living in the world

in abject poverty, meaning resources of less than $1.25 a day.

These data from 2005 show that we have a long way to go before reaching

the Millennium Development Report targets for 2015 just around the corner.

Population growth continues to be a major challenge for our food security and for

the ability to bring people out of poverty and to interrupt that vicious cycle.

Most of the growth now is in less developed countries,

meaning low income and lower middle income countries.

In the high income countries, in fact, there are several places in

the world now where replacement rate, fertility rates of 2.1,

are not being met, that in fact there is a population decrease,

because total fertility has fallen to as low as 1.3 or 1.4.

Projected growth shown in this chart has concentrations of high fertility and

high population growth rates across the heart of

Africa down into Southern Africa there is a very,

very impressive decrease or stabilization of population growth in China,

an actual diminished population growth in the Russian Federation.

Other pockets of very low population growth can be seen in southern Europe,

the Iberian Peninsula and pockets in Latin America.

Despite these trends in population growth,

we now have about 75% of the world's population living in countries

where resource extraction and depletion has exceeded resource capital.

In other words, just as you wouldn't want to draw down on the principal in

your investment portfolio, those of you who have an investment portfolio,

because that would deplete the very nature of the resource upon which you

might depend for interest and so on.

We are now living as though the whole world is one great banking system and

we are spending our principle, ending up with severe resource depletion.

The consumption of Earth's resources now exceeds our capacity for

renewal by about 30%.

The resource extraction is increasing steadily and some of the newly emerging

economies, such as Brazil, Russia, Indonesia, China and India.

One of the most critically important resources is fresh water.

Worldwide, the hydrologic cycle accounts for only about 2% of all water

on Earth, most of it of course is in our large seas and much of

our fresh water is actually locked in the ice cap of Greenland and Antarctica.

But the extractable water now accounts for about 93% of water use going toward

agriculture, deep tube wells, such as illustrated in this photograph.

If you fly across the United States,

you get into the arid regions of the southwest, and

you look down from 35,000 feet and you see these blue green circles.

These are the large pivot irrigation systems that are drawing down,

the Ogallala Aquifer.

Aquifers elsewhere in the world, such as the northern plain of China and

the Punjab, both of them being the bread baskets respectively of China and

India, are now being depleted at the rate of

about 20 centimeters per year dropped in water table.

The direct relationship between the availability of water and

the world's ability to meet the nutrition requirements of the population

is impacted by this and we are going to face increasingly severe water shortages.

Water scarcity, pictured in this map of the globe, is of two types.

There's physical water scarcity, that is, that the hydrologic cycle just

simply does not provide enough, rainfall over that portion of the earth's surface.

Or, the runoff in river systems and so

forth has not been adequately captured and utilized to provide water.

Economic water scarcity shown in the dark purple,

is a problem of resource lack for capital improvements.

Simply not enough money available to build water systems,

to manage the hydrologic cycle that actually provides water in some abundance,

as I'll show you in the next slide.

With adequate investment in some of these areas, such as Peru, Bolivia,

parts of Northern Chile in Latin America, and that

broad swath across Sub-Saharan Africa, and to a lesser extent in South Asia.

We could improve greatly the accessibility of fresh water supplies for

human use, for agriculture, for industry, and for municipal use.

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