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Geography of Population 4

Feeding the hungry

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Population and food

World population growthT.R. Malthus and the problem of the carrying capacityFood requirementsMore food, less people or new thinking?

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World population growth

Year Millions + % per annum Years for doubling

1750 791

1800 978 0.43 161

1850 1,262 0.51 136

1900 1,650 0.54 128

1930 2,070 0.76 91

1950 2,916 0.98 69

1960 3,037 1.86 37

1970 3.693 2.04 34

1980 4,449 1.88 37

1990 5,321 1.82 38

2000 6,100 1.38 51

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Consequences of growth

More space to live onMore space to create jobsMore space for transportation routesMore space to produce food... and what about the ecosystem?

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The food problem

What is nutrition?Intake of substances every living being (plants, animals, humans) need for growth and survivalOrganic substances (proteins, carbon-hydrates, fats), fibres, water, salt, vitamins, tracer elements

furnish energy, replace old body substances, create new body substances

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Equilibrium nutrition

Water, drinks

Cereal products, potatoes

Oil, fatSugar, sweets

Milk, milkproductsFish, meat, eggs, pulses

Fruit, vegetables

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Key factors

Supply and demand

Lifestyle Living standard

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Supply and demand

SupplyLand use (harvest rhythm, succession)DemandProduction areasTransportationStorage capacitiesNatural potential (soils, climate)Culture, attitudes

DemandSocial situation of con-sumers (age, habits)Economic situation of consumers (income, subsistence)Degree of urbanizationCulture, attitudesSupplyNumber of consumers

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T.R. Malthus

1766-1834 1797 priest (Church of England)1806 Professor for history and political economy (East India Company Hailesbury College)1798 ‘An Essay on the Principle of Population as it affects the Future Improvement of Society, with Remarks on the Speculations of Mr. Godwin, M. Condorcet, and other Writers‘ Contemporary of Adam Smith, David Ricardo, J.H. von Thünen

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Malthus‘ main thesis

Population increases faster than food production (geometric vs. arithmetic progression)This increase is due to an instinct-motivated reproduction of mankind rather than reproduction dictated by reason“Vice” (which included, for Malthus, contra-ception), “misery,” and “self-restraint” alone could check this excessive growth.

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Background to Malthus

Discussion about poor laws and poor housesAccording to Malthus, the dole contained in the poor laws encouraged the poor to have many childrenDispute with William Godwin (1756-1836), social philosopher and anarchist

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Critics of Malthus

The priest sees ‘bad morality’ as chief reason for the food problem very simple solution to the food problemThere are other problems than just foodElegant theoryPoor empirical basis

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Merit of Malthus

Points to a fundamental problemNo calculation of an upper limit of world populationProposes a vicious cycle: more people more food demand more food production more people more ...

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Carrying capacity: how many people on earth?

"Carrying capacity is the largest number of any given species that a habitat can support indefinitely." For human societies in a specific region, this has to be completed by the cultural and social particularities, the transportation possibilities, and the level of living

There is no simple answer to the question

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Range of carrying capacity estimates

Ravenstein (1891): 5.995 billionBallod (1912): according to lifestyle:- Japanese lifestyle: 22.4 billion- US lifestyle: 2.3 billionPenck (1925): 7.7 billionRevell (1976): 40 billionWesting (1990): 2 billion

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Influence of lifestyle

Estimates by Rees & Wackernagel (ca. 1995): Third World lifestyle: 4.5 billionEuropean lifestyle: 2.2 billionUS lifestyle: 1.1 billion

The World population obviously lives beyond its resources!

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Results

In this domain, the globe cannot be regarded as uniformCarrying capacity varies according to space and timeThe economic basis has to be taken into accountLevels of living are diverse and influence demandThere are no reserve areas availableThe tropical rainforest cannot be used for large-scale food production

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The tropical rainforest

A relatively closed ecosystemNo profound soil but only a superficial layerFalling leaves rot in the tropical climate immediately, and nutrients pass directly back into the plants (no accumulation in the soil)Felling the forests destroys this short-circuit cycle: agriculture is possible for a short time onlyAdapted agriculture: shifting cultivation

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Growth of food production

Malthus‘ pessimistic forecasts were not correctAgricultural reforms since the 19th century have increased the output:- better rotation technique (clover instead of fallows)- improved fertilizers- new food plants- land reforms (consolidation of holdings)

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Agricultural production in Valais (Swiss mountain canton)

18th century 1996

Wheat (tons per ha) c. 1.8 5.3

Milk (100 litres per cow) 800-1,200 4,500-6,000

Wine (100 litres per ha) 15-25 85

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Agricultural production in China

1957 1995 + %Population (mio) 647 1,211 87.2Cereals (mio t) 191 465 143.5Cereals per head (kg) 295 384 18.0Oil seeds (mio t) 4.2 22.5 435.7Oil seeds per head (kg) 1.7 6.7 294.1Red meat (mio t) 4.0 42.0 950.0Red meat per head (kg) 6.2 34.7 459.7

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Consequences

Increases in food production are possibleThere is enough food on earth in sufficient quantity for everyoneIt is just a problem of distribution

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What do we need?

Human wants and needs are not always the sameBest known need: energy intake, measured in calories or joulesFurther intakes: vitamins, proteins, tracer elements, fibres, liquids (water)

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Energy

Energy intake depends on sex and activity: men need more than women (natural body fat higher in women; activities higher with men)The estimated values vary, however:Basic value: c. 1 kcal per kg body weight of a man 1680 kcal for a man of 70 kgsBasal metabolic rate (at rest): c. 1.25 kcal per minute (man of 65 kgs) and 0.90 kcal per minute (woman of 55 kg) 1800 man, 1296 woman.

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Energy requirements

Heavy work (mining, lumbering, steel works): 4000 kcal +Medium activities (light industries, carpenters, painters, etc.): 3000 kcal +Light activities (professors, students, drivers, etc.): 2500 kcalWhere are the housewives?Below 2100 kcal: undernourishment

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The reality

Ethiopian farmers may have to cope with 1800 kcalMinimum in Asia is often at 1600-2000 kcalMountain farmers in 18th century valley of Uri (Switzerland) had around 2500 kcal

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Global food situationDaily calorie

intake% vegetable

calories% of

requirementSub-Saharan Africa 2 250 93.4 93.7

Middle East 3018 90.6 119.7

South Asia 2215 92.9 98.7

Far East 2638 79.3 113.1

Latin America 2699 82.5 115.3

Europe & CIS 3422 69.169.1 132.6132.6

North America, Oceania 3586 69.169.1 136.2136.2

World 2697 84.3 112.7

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Interpretation

Although the global situation seems satisfactory, there are substantial regional differencesThe lack of animal calories makes itself felt in Africa and South AsiaThe North is ‘overfed’: given the dominance of the sedentary work, we eat far too muchThe table does not take social differences into account: the rich in the South are not hungryThis points to a grave problem of distribution of food

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Evolution of undernourishment in the World (FAO Technical report 2000)

1970 1990 1995 2015

Total undernourished (mill.) 960 830 790 430

% of world population 24 16 13 5

absolute change - 360 - 40 - 360

% change - 8 - 3 - 8

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Really a solution?

Undernourisment cannot be completely eradicatedThe WHO certainly pays a lot of attention to the food problemHowever, there is also wishful thinking: is the same rate of decline possible 1995-2015 and 1970-90?

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Proteins: varying opinions

What is the minimum quantity of daily protein intake (gram per kg weight)?- League of Nations, 1935 1 gr.- FAO/WHO, 1955 0.52 gr.- FAO/WHO, 1963 0.71 gr.- FAO/WHO, 1971 0.57 gr.- FAO/WHO/UNU, 1985 0.75 gr.

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Interpretation

There is no consensus among scientists as to the basic requirement12-17 % of the calories can be taken in form of proteinsA deficit of 8 % (infants) and 5 % (adults) with protein intake means undernourish-ment

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Recommended Nutrient Intakes Age Calcium

mg/dayVitamin A

μg/day Vitamin C

mg/day

0-6 months 300 375 25

7-9 years 700 500 35

Males 19-65 1,000 600 45

Females 19-50 1,000 500 45

Females 50-65 1,300 500 45

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The potato in 3 shapesNutrient etc. Baked Boiled skin Boiled peeled

Water (%) 71.2 77.0 77.5

Energy (kJ) 456 365 361

Protein (g) 2.3 1.9 1.7

Iron (mg) 1.4 0.3 0.3

Calcium (mg) 10 5 8

Fat (g) 0.1 0.1 0.1

Potassium (mg) 418 379 328

Vitamin C (mg) 13 13 7

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Efforts to increase food production

1950s – 1990s: Cereal yield per capita rose from 283 to 349 kg (+ 23 %)In the same time, the harvested surface declined from 0.235 to 0.127 ha per capita (- 46 %)Yields per hectare increased from 1205 to 2745 kgs (+ 128 %)

More is produced on less surface available – for how long?

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Conclusions

Food production has increased worldwideThe absolute increase has been greater in the South than in the NorthThe per capita increase has been lower in the South than in the North thanks to the population growthIn Africa, the absolute production has declinedThe food issue is a problem of distribution

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The future? Solutions?

The food problem is a social issueDistribution Access to foodFood pricing (for the poor)No speculative storing of foodNo wars (that destroy land and harvests)Environmentally friendly farmingLess fat people in the NorthChange of attitudes

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A few options

Better use of energyCare for the landMarine resources

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Better use of energy

1 vegetable calorie (e.g. wheat) is transferred into 1 bread calorieTo obtain 1 animal calorie, the following vegetable calories are needed:

- 12 for chicken meat- 4 for eggs- 3 for pork- 5 for milk

This under conditions of industrial agriculture (mass animal production).

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Care for the land

Fight soil degradation (less fertilizers)Prevent soil erosion (stone walls, hedges, contour ploughing)Improve irrigation (combination with drainage)Avoid monocultures (unilateral use of nutrients)

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Land in China: growth and decline

12

34

0

20

40

60

80

100

120

140

160

mio ha

Cultivated surfaceCropped surface

19791984

1993

1957

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Fertilizer efficiency in China, 1969-93

-10

0

10

20

30

40

50

60

1969

kg g

rain

/kg

nutr

ient

Dünger-Effizienz in China, 1969-93

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Marine resources

This is no longer the reserve we once thought (overfishing, stock depletion)Improved management of fisheries towards a sustainable useModerate aquaculture (labour intensive, not capital intensive, real needs, not luxury wants)Market orientation (according to the needs of the people)Promote local fishermen and low-intnesity fishing in order to maintain the stocks and secure jobs

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Was Malthus right?

Current trends show that the world popula-tion is no longer growing as fast as 30 years agoFood production has increased, but so has population: we are as far as 1950!The decline in the growth of food produc-tion may be the result of excessive stress on the ecosystem

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Population and cereal production growth, 1950-2000

0

50

100

150

200

250

300

1 2 3 4 5 6

Cereal yield index Population index1950 2000

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Stress on the ecosystem: Aral Sea

Aral Sea: a basin east of the CaspianThe two rivers of the Aral Sea (Amu Darya and Syr Darya) have been used for the irrigation of intensive cotton fields upstreamThe surface of the Sea has been shrinking since the 1950s (65,000 40,000 sqkm)

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The ecological limits: irrigation and Lake Aral

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The decline of Lake Aral

Desiccation of the Aral sea, 1995 to 1996: area decreased by 3885 km2, volume by 36 km3. Salinity: 46 g/l

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Aral Sea: former beach

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Genetically modified food – the solution?

Expectation 1: resistence to pests reduces lossesExpectation 2: better seeds give higher yieldsProblem 1: pests can adapt to new circumstances, cannot be eliminatedProblem 2: dependency from hi-tech industrial seed producersProblem 3: loss of genetic potential and biodiversity for the time after biotechnologyProblem 4: what happens in the long term?

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Other solutions?

More technology into agriculture?Intensive production where conditions are optimal?Free world market for food?Radical antinatalist population policy?

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A change in Northern attitude

Slimming of the people in the NorthRedefinition of ‘nutrition‘ in the NorthLess exploitation of the SouthMore respect for the food in the North

Food is precious, more than just a commodity to be used and thrown away.