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World Population Growth Constraints and Challenges to Global

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					 World Population Growth:
Constraints and Challenges
  to Global Food Supply



    Frederick T. Oresanya
            Introduction
 Art of farming discovered 10,000 years
  ago
   • Spread through migration
   • Triumph over hunting & gathering era
 World pop.  from 10 millions to about
  200 million A.D.
 Below 700 millions until Industrial
  Revolution in the 18th century
            Introduction
 1798 Warning: Population growth may
  outstrip food supply
   • Famine, pestilence, war
 Geographical & economical famine
 War for land & water
 Estimated 1 billion hungry & malnourished
 Estimated 19,000 death d-1 from hunger &
  malnutrition (WHO, 1996)
Population: Numbers & Growth

 Accelerated growth after 1900
 More than double from 2.5 billion in
  1950 to 6 billion in 1998 (ZPG, 1998)
 Growth enhanced by  fertility rate, 
  life expectancy and  death rate
 1.7%yr-1 (doubling time of 40 years)
Fig 1.                   Population Growth Scenario

                        25         Unfavorable
 Population (billion)




                                   Probable
                        20
                                   Ideal
                        15
                        10
                        5
                        0
                             1965 1980 1995 2010 2025 2040 2055 2070 2085 2100
                                                   Year

                                                          Kim & Han, 1998
     Table 1.   World Largest Countries
                1998                       2050
Rank    Country    Population     Country      Population
                     (millions)                 (millions)
1        China        1,255        India         1,533
2        India          976        China         1,517
3        U.S.A         274         Pakistan        357
4        Indonesia     207         U.S.A           348
5        Brazil        165         Nigeria         339
6        Pakistan      148         Indonesia      318
7        Russia        147         Brazil         243
8        Japan         126         Bangladesh     218
9        Bangladesh    124         Ethiopia       213
10       Nigeria       122         Iran           170
                                            UN, 1996
     Food: History & Supply

 1950-1984: Introduction of high-yield
  crops & energy intensive agric.
  World grain output
 Green Revolution (G.R.)
   •  use: Fossil energy for fertilizer,
    pesticides, irrigation, improved seeds
 G.R. Environmental sustainability??
 Food: Availability & Consumption


 Grain: Consumed directly & indirectly
 Useful measure in estimating future
  food need
 Growing affluence:  indirect grain
  consumption
         Food Production

 Pre 1950: Greater area of land cultivated
 Irrigation: Rapid spread
 1960s: Nations self-sufficient in food
 Irrigation: Becomes more difficult &
  expensive
 An unforseen “dust bowl”
                            Fig 2.   Food Production

                     200
Index (1960 = 100)




                     180             Population
                                     All food items
                     160             Feed per person
                                     Agric. Land
                     140
                     120
                     100
                     80
                           1960 1964 1968 1972 1976 1980 1984 1988 1992 1996
                                                   Year

                                                          Kim & Han, 1998
            Fig 3.   World Meat Production Per
                       Person, 1950-97
            40
            35
            30
Kilograms




            25
            20
            15
            10
             5
             0
                 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 1997
                                         Year

                                                    FAO, 1998
                 Fig 4.   World Fish Production
            20

            15
Kilograms




            10

             5

             0
                  1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050
                                           Year

                                                  Brown et al., 1998
How Many People Can The Earth
         Support?

 What is the earth’s carrying capacity?
  • At what level of material well-being?
  • In what physical, chemical & biological
      environment?
  •   With what variability or stability?
  •   At what level of consumption?
  •   For how long?
How Many People Can The Earth
         Support?

 Is the earth able to support 12 billion
  in 2050 without jeopardizing its
  ability beyond then?
 Is it enough time for agriculture to
  revolve?
 What is the impact of increasing
  population on the climate?
            Global Carbon Emission Per
                  Fig 5.

       Person, 1950-98, Projections to 2050
                  2
Tons of Carbon




                 1.5

                  1

                 0.5

                  0
                       1950 1960 1970 1990 2000 2010 2020 2030 2040 2050
                                             Year
                                                    Marland et al., 1998
                    Fig 6. Average Temperature at the
                          Earth’s Surface, 1880-1998
                  14.8
                  14.6
Degrees Celcius




                  14.4
                  14.2
                    14
                  13.8
                  13.6
                  13.4
                         1880 1890 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 1998
                                                      Year


                                                         Marland et al., 1998
   Scenario For Increase Food
           Production

 Varied increase in food production.
  About 0.5 & 0.3% per year (Kim & Han, 1998)
 3 scenario
   •  yield
   •  arable land
   •  irrigation
              Fig 7.   World Grain Production Per
                         Capita,1950-1998
            400
            350
Kilograms




            300
            250
            200
            150
            100
                  1950 1954 1958 1962 1966 1970 1974 1978 1982 1986 1990 1994 1998
                                               Year

                                                           USDA, 1998
 Fig 8.   Arable Land per Person
          Population (Billion)   Arable Land (ha)


1950
1960
1970
1980
1990
2000
2010
       8 7 6 5 4 3 2 1 0 0.05 0.1 0.15 0.2 0.25
                 Billion                 Hectare
                                 Kim & Han, 1998
 Table 2.   Land Surface (M ha)


Globe Total Land Surface           13,000
Forest & Savannah                   4,000
Area Utilized for Food            ~ 4,600
 - Pasture & Rangeland              3,100
 - Cropland Total                   1,500

                           WRI, 1992
           Gains and Losses of
     Table 3.
       Arable Land (M ha/year)
Forest and Savannah Loss           20 (~ 0.5%/year)
Cropland Lost or Abandoned
      Erosion                      5-7
      Urbanization                 2-4
      Salinization & waterlog      2-3
Total Cropland Losses              >10
Cropland Gain (deforestation)      16

Cropland Net Gain                  5-6
                                WRI, 1992
 Table 4. ForestedArea Per Capital, 1995
         with Projections to 2050
Region               1995                 2050
                             (Hectares)
Africa               0.32                 0.11
Asia                 0.12                 0.08
Europe & Russia      1.1                  1.28
N. & C. America      2.07                 1.54
Oceania              3.32                 2.02
S. America            2.14                1.30
World                0.59                 0.36
                             Brown et al., 1994
          Got Water?
  “The real limit for the future
 growth of world’s population
  does not lie in the potential
amount of agricultural land, but
 in the total amount of water.”
               Herman Wagner 1923
      Where is the Water?
 Depleted aquifer; falling water table
  • U.S southern great plains &
    southwestern
  • Punjab & several states, India
  • Central & northern China
  • Belgium & the Netherlands
  • Fossil aquifer in Saudi Arabia
 Nile: An endangered river
       Where is the Water?

 Irrigation source of additional output
   • In 1950, ~94M ha irrigated land, in 1998,
    ~260M ha
 40% of total world grain harvest
  today comes from irrigated land
  (Brown et al. 1998)
                       Irrigated Area Per Capital,
           Fig 9. Global
              1955-95, with Projections to 2055

           0.05
           0.04
Hectares




           0.03
           0.02
           0.01
             0
                  1955 1965 1975 1985 1995 2005 2015 2025 2035 2045 2055
                                           Year


                                                 FAO, 1998
           Table 5.   A Thirsty World
Country                   1990          2025
                       (m3/person)   (m3/person)
Egypt                    1,070           620
Ethiopia                 2,360           980
Somalia                  1,510           610
Libya                      160            60

Iran                    2,080           960
Saudi Arabia              160            50
Haiti                   1,690           960
Peru                    1,790           980
                                 Gleick,1996
              Challenges


 Improved growth rate
 Improved feed efficiency/  animal waste
 Improve carcass composition
 Increase milk yield protein
              Challenges

 Improve reprod. Performance/  mortality
   • Super sow: >20 piglets???
   • 2 eggs/day???
   • Gain time on gestation length???
   • Twinning in cow: a minimum requirement?
 Defend tenaciously our practices
                      Summary
             Grain & Food
                Prices
                                                   M.C.
              Animal Protein                      H2O
                 Demand                          Demand

    Econ.                          Food        Arable Land
                       Pop.
Dev./Affluence                     Demand          Demand
                                     M.C.
                 O3 Depl./  CO2                 Deforest.

                                   Climatic 
                                     M.C.
                 Conclusion

 World population is projected to increase well
  into the 21st century
 Related increase in food demand (especially
  animal protein)
 Intensified efforts to raise animal productivity
  (especially reproductive and feed efficiency)
           Quotes of a Decade

“It must be obvious by now that further
population growth in any country is
undesirable.” Prince Philip 1990
“…..there is no country in the world in
which people are satisfied with having
barely enough to eat.” Kingsley Davis 1991
“I know of nine-year-old farm lads in jail for
murder over water disputes.” Syed Ayub Qutub
1993
“World peace will not be built on empty
stomachs and human misery.” Norman Borlaug
1995
“If our population continue to grow as it is

				
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