Population pressure●●●

Environmental health (9) on 7th Dec. 2023(cf.) Chapter 15 "Healthy Communities" of Frumkin's text 3rd ed.
Key concepts●Fertility rates are falling in some regions, global population still
grows, especially in poor countries●
Global population is becoming increasingly urban●
Population growth with affluence/technology (using resource)exerts pressures on natural resources and ecosystem integrity●
Ecological footprint is to measure impact of population andresource use on the ecosystem●
Carrying capacity = No. people who an ecosystem or theentire Earth can support●
Limiting population growth and reducing per capita resourse
use contribute to environmental healthPopulation and resource use are uneven
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Current world population

https://www.worldometers.info/world-population/
Fertility declines in virtually every region of the world●
Rapid in Europe, Asia, North America "birth dearth"●
Africa's fertility drops due to HIV/AIDS (40 million people
are HIV positive, 75% of them live in sub-Sahara), but thedrop is attenuated due to international programs incl.
UNAIDS
UN-DESA (United Nations Department of Economic and SocialAffairs), population division's report●
Annual population growth ~ 78 million ~ slightly more than
100 million during 2014-2017●
Projection: 8 billion by 2025, 9.1 billion by 2050●
99% growth occurs in the world's poor, developing
countries (sub-Saharan Africa, Middle East, South Asia).
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90% of 1.2 billion teenagers live in developing countries
https://population.un.org/wpp/Graphs/Probabilistic/POP/TOT/900

Measuring population impact
See, https://ecotope.org/blog/saved-by-ester-boserup/
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Malthus T (1803): Human populations have a tendency
to increase exponentially, unless limited by starvation,disease or fertility limitation policies, but agriculture
only increased its productivity in linear fashion,
resulting in famines
Neo-malthusians: Population is a driver of negativeenvironmental changes
Boserup E (1965): Population growth is the force
stimulating technological change and intensification.
Increases of population density resulted in land
scarcity, which triggered agricultural intensification
through application of improved technology (e.g. better
tools, irrigation, terracing, shortening of fallows)
Ehrlich PR, Holdren JP (1971): Developing countries
have large impact on environment due to rapid
population growth, developed countries do so due tohigh affluence and technology level.
* Impact = Population x Affluence x Technology (I=PAT)
see, Ehrlich PR, Ehrlich AH (1990) The Population
Explosion, Touchstone, too.
Lomborg vs Bongaarts and others●
Debates between optimists andpessimists about the population
growth exceeding environmentallimits.
●
https://doi.org/10.1007/s11111-023-00424-5

Ester Boserup
1910-1999
Danish Economist

Long term history ofworld population growth●●

Deevey (1960) https://www.jstor.org/stable/10.2307/24940623●
Log-log graph shows a sequence of multistep logarithmic growth●"Three population surges" correspond to cultural revolution (use of stonetools), agricultural revolution (farming with sedentary life), scientificindustrial revolution (use of fossil fuels and machinery)
Annual increase rate since 1750 (bars in the Figure 1 top right)●
Before 1750, less than 0.5%●
1750-1930, 0.5-1%●
After 1950, higher than 1.6%, mostly in developing countries

Population and urbanization
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World is in the middle of urban revolution
Global population live in urban area●
More than 50% (2008) → 60% by 2030●
UN-DESA: 3.3 billion (2007) → 6.4 billion (2050)
Big cities in Africa are growing at 4% per year. It will
be double within 20 years
Infrastructure of most cities in developing countries
cannot keep pace with such rapid/continuous urban
growthUrban growth ← fleeing collapsing rural economies,lack of rural infrastructure/services, landlessness, lackof rural employment opportunities (push factors)
On the other hand, urban sprawl also occur in someplaces (emphasis on private spaces, large footprint).

(Source: Frumkin's text 3rd Ed.)

Population and environment
https://assets.wwf.org.uk/downloads/city_footprint2.pdf●●

Ecological Footprint●(Wackernagel and Rees, 1997) A
measure of how much area of
biologically productive land and water
an individual, population or activity
requires to produce all the resources it
consumes and to absorb the waste it
generates using prevailing technology
and resource management practices.
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Usually measured in global hectares.
Because trade is global, an individual orcountry's footprint includes land or sea
from all over the world.
Carrying Capacity●
The number of people the Earth (orspecified region) can support. Estimates
depend on what's included and how it's
measured●vegetarian diet with 2500 kcal/day → 40
billion, meat diets → 10 billion, if
developing population live at the standardof developed, 2 billion

Population → Land Use (← Urbanization, Policy,
Economic growth incl. industrialization)→ Biodiversity loss, CO2 emission
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Weber H, Sciubba JD (2019) The Effect of Population Growth on theEnvironment: Evidence from European Regions. European Journal ofPopulation, 35(2): 379-402.
https://dx.doi.org/10.1007%2Fs10680-018-9486-0
de Leon Barido DP, Marshall JD (2014) Relationship between
urbanization and CO2 emissions depends on income level and policy.
Environmental Science & Technology, 48: 3632-3639.
https://doi.org/10.1021/es405117n
Foley JA et al. (2005) Global consequences of land use. Science, 309:570-574. https://doi.org/10.1126/science.1111772
Regression model in IUSSP conference (2001) states that the impact of
population on CO2 varies by affluence.
https://iussp.org/sites/default/files/Brazil2001/s00/S09_04_Shi.pdf
Casey G, Garol O (2017) https://doi.org/10.1088/1748-9326/12/1/014003
D’Sauza R (2022)
https://www.orfonline.org/expert-speak/population-drives-climate-change/

Population-Environment Scoreboard●●●"Earth Summit" (at Rio de Janeiro, 1992) : set specific goals* Rio+5 (UN General Assembly, 1997): little progress or worsened* Rio+20 (UN Conference on Sustainable Development, 2012)
Poverty had increased, partly due to population growth
Situation of environments●
Arable Land: Degraded, Small scale farmers cannot produce
enough food to feed their families●Freshwater: Growing populations place pressure on freshwatersupplies. In 1995, 2.3 billion lived in water stressed areas. Lackof clean water: 1 billion in 1990, 1.2 billion in 2007. Chronic
water shortages will be the most limiting factor on future
economic development. World Resource Institute prospects 3.5billion people live under water-shortage stress by 2025.
●Oceans: Coastal wetland have deteriorated. 40% of coral reefs
were lost. FAO (2009, 2011) reported 3/4 of world majorcommercial fish stocks are fully/over-exploited or depleted. 2billion people depends on seafood for protein
https://www.fao.org/3/i2389e/i2389e.pdf●Forests: Deforestation increased (Brazilian amazon, rate was70% increased in 1992-2002). 37 million ha forest was lost in2000-2005.
●Biodiversity: Losing species at 100-1000 times faster thannatural loss. During 1990s, 27,000/yr animal/plant species
extinct. IUCN Red list: 41415 species. Species diversity isessential for human health as the source of medicine and food.
●Climate Change: Population growth → energy use → CO2 →global warming and climate change. Though COP3 FCCC
Kyoto Protocol → COP21 Paris Agreement, still ongoingPoverty and population
Rapid, unsustainable population growth = a principal
contributor to poverty●1/4 ~ 1/5 of Earth's people live in extreme poverty(absolute poverty: spend less than US$1/day in 1985,$1.25/day in 2008, $1.90/day in 2015)(cf.) Relative poverty (the poorest segment ~ 1/5 or 2/5~ of the population, sometimes less than half of themedian income) should also be paid attention.
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https://openknowledge.worldbank.org/bitstream/handle/10986/11985/9780821376133.pdf

Lower fertility and slower population growth have notbrought an improved living standard for the average
person. In 1980, about 2.5 billion people lived in lessthan $2 per day.
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Extreme poverty decreased during recent decades (from1.9 billion in 1981 to 1.8 billion in 1990, 1.4 billion in2005) partly due to MDG1●

Environmental Distress Syndrome
Population pressure and excessive resource use
threats the health of the environment●
Deteriorating environmental conditions andconcomitant threats to human health●Five symptoms●

Reemerging/Emerging infectious diseases●
Loss of biodiversity●
Growing dominance of generalist species●
Declines of pollinators are intrinsic to the propagationof flowering plants.
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Proliferation of harmful algal blooms along the world's
coastlines → outbreaks?
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