GEOG10001 Lecture Notes - Lecture 7: Diminishing Returns, Crop Yield, Technological Change
16 May 2018
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LECTURE 7: NEO-MALTHUSIAN THEORIES OF FAMINE
• Neo-Malthusians: see population as a meta-pressure on environment
o Solution: decrease population growth
o Key relationship: food supply + population
• Abundance theory argues famines occur when food supply per capita decreases under a threshold
• Diminishing Returns: more effort delivers increased output, but at a diminishing rate
o Reasons: over-use of fertiliser, deterioration of soil + limits of water availability for
irrigation
DEMOGRAPHIC TRANSITIONS
• Describes changes in fertiliser + mortality in relation to economic development
• Decline from high level death rates +decline of high level death rates
• Long-term trend declining trend of fertility rate in Asia to reach 2.1 currently (replacement rate)
• Can we avert food shortages by controlling population?
4 Stages of Demographic Transition
To achieve falling fertility rates
• Contraception + family planning
• Political + social stability
• Women education
o Huge role, research shows empowerment leads to fewer children
CONSUMPTION + AFFLUENCE
• Growth of economy is driving environmental crisis
• Global consumption: 1.7 billion are global class of consumer
o Developed countries: consume far more than % population
• Growing middle class (China + India) – taking over the consumer class
o Tipping point: consumption patterns + population = environmental crisis
Carrying Capacity
• Physical, chemical + biological limits on the environment
• Equity issues: who gets to consume?
• How do we + do we place limits on consumption?
• Are we reaching carrying capacity – increases in consumption across all sectors
• Urbanisation: cities are nodes of consumption
THEORIES OF TECHNOLOGICAL INNOVATION
Two contrasting views:
• Malthus: food production can’t keep up
• Boserup: people will innovate when needed, gradual adaptation in response to population density, people are proactive agents
(shape environment to our needs
Green Revolution (began in 1960’s)
• Main features: Irrigation, crop selection (dwarf varieties) + agrochemicals
• Massive technological intervention in agriculture
• Implementation: most favourable + areas with success, irrigation well developed, credit access, input access
o Required government investment, favoured some areas over others, uneven access to revolution
• Dramatic transformation of social + economic relations
o Capitalist market introduced in rural areas,
• Increase in productivity
• Major growth in yields since 1960 = reduction in food prices
o Led to increases in population growth
Why?
• Easier than land reform
• Technological change + improvements
• Scale neutral: same for big + small farms/operations
• No need for land expansion due to intensification
Demographic Transition in Bangladesh
1970’s
• Contraception + family planning
saw a decline in fertility rate, first
increases while second decreases
• Led to longer life expectancy
I = P.A.T
Where:
I = Environmental Impact
P = Population
A = Affluence ($/person)
T = Technology (impact/$)
1. High death rate, high birth rate
(pre-industrial)
2. Falling death rate, high birth rate
(better sanitation, diet + health)
3. Low death rate, falling birth rate
(economic developments, female
equality, education)
4. Low death rate, low birth rate
Limitations
• Impacted on poor more than expected – had to turn to
markets
• Regional benefits uneven
• Political impacts – conflict
• Degradation + environmental problems
• Dependence on machines + materials – heavy energy input
Theory of Diminishing
Returns
Document Summary
Neo-malthusians: see population as a meta-pressure on environment. Abundance theory argues famines occur when food supply per capita decreases under a threshold. Diminishing returns: more effort delivers increased output, but at a diminishing rate. Reasons: over-use of fertiliser, deterioration of soil + limits of water availability for irrigation. Describes changes in fertiliser + mortality in relation to economic development. Decline from high level death rates +decline of high level death rates. Long-term trend declining trend of fertility rate in asia to reach 2. 1 currently (replacement rate) Returns: high death rate, high birth rate (pre-industrial) Falling death rate, high birth rate (better sanitation, diet + health) Low death rate, falling birth rate (economic developments, female equality, education) 1970"s: contraception + family planning saw a decline in fertility rate, first increases while second decreases. To achieve falling fertility rates: contraception + family planning, women education. Huge role, research shows empowerment leads to fewer children.
