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11/1/2016
1
World Population,Demographic Transition
Model,Primate Cities
http://navigator‐iup.passhe.edu/login?url=http://digital.films.com/
PortalPlaylists.aspx?aid=1972&xtid=34174
Thomas Malthus (Malthusian Theory)• Famously predicted that the population of the Earth would steeply rise after the industrial revolution
• Authored , An Essay on the Principle of Population
• Several editions from 1798 – 1826
• Theory states that Population grows geometrically (1, 2, 4, 8…) while food supply grows arithmetically (1 ,2 ,3, 4 ,5…)
• Suggested that as population grew faster than food supply, ‘checks’ on population must occur
• War, disease, famine
• Said the fertility of the poor put pressure on industrial capitalism
• Anti‐Capitalist critics argued it was not the poor who were pressuring production, it was the increased rate of production that was pressuring the poor!
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World Population Distribution Stats:• Uneven population distribution uneven population density
• World is increasingly urbanizing • 50% of the world’s population lives in cities
• Europe and South America are two of the most urbanized regions with close to 80% urbanized
• 90% of all people live north of the Equator
• 60% live between 20° and 60° North (Temperate Climate)
• 50% of the world’s population live on just 5% of its land area• Almost 90% of the population live on less than 20% of its land area
• People favor lowland areas over high altitude areas• 80% live below 500 meters above sea level
• Coastal areas have the densest settlement• 60% of the world’s population lives within 100 km of the ocean
Population Distribution of Latin America
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Rural‐to‐Urban Migration in Latin America
Demographic Transition Model (DTM)
• A general rule‐of‐thumb that identifies periods of development with population characteristics
• The DTM is based on variations in • Crude birthrates – the annual number of live births per 1000 population
• Crude death rates – the annual number of deaths per 1000 population
• Five Phases identified:• Phase 1 – High births, high deaths
• Phase 2 – High births, declining deaths
• Phase 3 – Declining births, Low deaths
• Phase 4 – Low births and low deaths
• Phase 5 – Deaths higher than births
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Characteristics of DTM Phases:
• Phase 1 –High births, high deaths
• Pre‐industrial economy
• Phase 2 –High Births – Declining Deaths
• Developing Country
• Improving food and water supply
• Improving Sanitation
• Improvements in farming technology
• Improvements in education
• Results in a large population increase
Many Latin American countriescurrently in this phase, including;
• Bolivia• Peru• Paraguay• Guatemala
No Latin American country is in this phase today – all have passed through this phase
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Characteristics of DTM Phases:• Phase 3 –
Declining Births – Low Deaths• Contraception• Wage increases• Urbanization• Reduction of subsistence agriculture• Increase in status and education of women
• Reduced child labor• Increase in parental investment in children
• Population growth begins to level off
Brazil and Mexico in this phase
• Phase 4 –Low births and low deaths• Stabilization of population• Idealized end point
Uruguay, Cuba in this phase,
Chile and Argentina approaching
• Phase 5 –Deaths higher than births• Shrinking population• Threat to Industrial Societies• Norm in post‐Industrial/deindustrialized societies
• Mitigated through immigration
No Latin American country in this phase
Phase 3 Line Graph
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Phase 4 Line Graph
Phase 1 – High births, high deaths
Phase 2 – High births, declining deaths
Phase 3 – Declining births, Low deaths
Phase 4 – Low births and low deaths
Phase 5 – Deaths higher than births
Mexico is emerging out of Phase 2 and into Phase 3
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Population Pyramids ‐Mexico
Notice top age is 80+ years
Population Pyramids
Notice top age is 75+ years Notice top age is 100+ years
All of Latin America Mexico
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Population Density• Population Density – is the number of people living per geographic unit (i.e., per square mile or per square kilometer)Examples:
“Urbanized Areas” of the USA
http://en.wikipedia.org
“Urban Areas”For the 2010 census, the Census Bureau redefined the classification of urban areas to "a densely settled core of census tracts and/or census blocks that meet minimum population density requirements, along with adjacent territory containing non‐residential urban land uses as well as territory with low population density included to link outlying densely settled territory with the densely settled core. To qualify as an urban area, the territory identified according to criteria must encompass at least 2,500 people, at least 1,500 of which reside outside institutional group quarters."
Urban Areas of the United States of America[1]
Rank Name[Note 1]Population
(2010 Census)Land Area(km²)
Land Area(sq mi)
Density(Population / km²)
Density(Population / sq mi)
1 New York‐‐Newark, NY—NJ—CT 18,351,295 8,936.0 3,450.2 2,053.6 5,318.9
2Los Angeles‐‐Long Beach‐‐Anaheim, CA
12,150,996 4,496.3 1,736.0 2,702.5 6,999.3
3 Chicago, IL—IN 8,608,208 6,326.7 2,442.8 1,360.6 3,524.0
4 Miami, FL 5,502,379 3,208.0 1,238.6 1,715.2 4,442.4
5 Philadelphia, PA—NJ—DE—MD 5,441,567 5,131.7 1,981.4 1,060.4 2,746.4
6 Dallas‐‐Fort Worth‐‐Arlington, TX 5,121,892 4,607.9 1,779.1 1,111.5 2,878.9
7 Houston, TX 4,944,332 4,299.4 1,660.0 1,150.0 2,978.5
8 Washington, DC—VA—MD 4,586,770 3,423.3 1,321.7 1,339.9 3,470.3
9 Atlanta, GA 4,515,419 6,851.4 2,645.4 659.0 1,706.9
10 Boston, MA—NH—RI 4,181,019 4,852.2 1,873.5 861.7 2,231.7
11 Detroit, MI 3,734,090 3,463.2 1,337.2 1,078.2 2,792.5
12 Phoenix‐‐Mesa, AZ 3,629,114 2,969.6 1,146.6 1,222.1 3,165.2
13 San Francisco‐‐Oakland, CA 3,281,212 1,356.2 523.6 2,419.5 6,266.4
14 Seattle, WA 3,059,393 2,616.7 1,010.3 1,169.2 3,028.2
15 San Diego, CA 2,956,746 1,896.9 732.4 1,558.7 4,037.0
16 Minneapolis‐‐St. Paul, MN—WI 2,650,890 2,646.5 1,021.8 1,001.7 2,594.3
17 Tampa‐‐St. Petersburg, FL 2,441,770 2,478.6 957.0 985.1 2,551.5
18 Denver‐‐Aurora, CO 2,374,203 1,730.0 668.0 1,372.4 3,554.4
19 Baltimore, MD 2,203,663 1,857.1 717.0 1,186.6 3,073.3
20 St. Louis, MO—IL 2,150,706 2,392.2 923.6 899.0 2,328.5
27 Pittsburgh, PA 1,733,853 2,344.4 905.2 739.6 1,915.5
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http://www.newgeography.com
• The least dense urban areas with more than 2.5 million population are all in the United States.
• The least dense is Atlanta, with 1800 people per square mile or 700 per square kilometer.
• The second least dense is, perhaps surprisingly, Boston, despite its reputation for high density.
• Boston's population density is 2200 per square mile or 800 per square kilometer.
• Also, perhaps surprisingly, Philadelphia is the least dense urban area in the world with more than 5 million population, while Chicago is the least
dense urban area of more than 7.5 million.
http://www.newgeography.com
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Global Population Densities
http
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Primate City (a result of rapid urbanization)
• A primate city is the major city of a country, serving as the financial, political, and population center and is not rivaled in by any other city in that country
• In general, a primate city must be at least twice as populous as the second largest city in the country
• The presence of a primate city in a country usually indicates an imbalance in development
• An expanding core
• A stagnant periphery
Some Primate Cities of Latin America include:
Central America:•Mexico City, Mexico•Guatemala City, Guatemala•Havana, Cuba•Managua, Nicaragua•Panama City, Panama•Port‐au‐Prince, Haiti•San José, Costa Rica•San Salvador, El Salvador•Santo Domingo, Dominican Republic
South America:•Buenos Aires, Argentina•Caracas, Venezuela•Lima, Peru•Montevideo, Uruguay•Santiago, Chile
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GINI Coefficients• The GINI Coefficient is a useful metric for understanding the state of cities (or countries) with
regard to distribution of income or consumption
• It is the most widely used measure to determine the extent to which the distribution of
income (or consumption) among individuals (or households) deviates from a ‘perfectly equal
distribution’
• Equal Distribution (of income) meaning every individual has an equal amount of income
• Not going to happen, correct? But it does give us an indicator as to how the income in a place
is distributed throughout the population – and that is useful!
• The data used here is supplied by the United Nations and is collected from national surveys
and censuses (which will each have a different level of accuracy)
• Most GINI coefficients are usually compiled for a region or country
• GINI coefficients for cities are a relatively new way using data to look a the income
distribution of cities
GINI Coefficients
• The GINI coefficient is derived from a statistical formula and expresses the degree of evenness or unevenness of any set of numbers as a number between 0 and 1
• based on the Lorenz curve which plots the proportion of the total income of the population (y axis) that is cumulatively earned by the bottom x% of the population
• A Gini Coefficient of 0 would indicate equal income for all earners
• A Gini Coefficient of 1 would mean that one person had all the income and nobody else had any
• So… lower Gini Coefficients indicate more equitable distribution of wealth in a society, while higher Gini Coefficients mean that wealth is concentrated in the hands of fewer people
• Sometimes the Gini Coefficient is multiplied by 100 and expressed as a percentage between 0 and 100. This is called the "Gini Index"
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What do the ‘coefficients’ mean?
The table below provides a general guide that is used to identify possible causes and consequences associated
with different GINI coefficient values
UN‐Habitat, ‘State of the World’s Cities 2008/2009. 2010
GINI Index – Income Disparity since WWIINotice the USA has an increasing GINI index (meaning income disparity is growing), and that the USA’s
GINI coefficient is much closer to that of Mexico than that of Canadawww.wikipedia.com, using World Bank data
Alertline
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Urban and Rural GINI Coefficientsfor select developing countries
Urban and Rural GINI Coefficientsfor select developing countries
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UN‐Habitat, 2009
LATIN AMERICA
Income Inequality GINI coefficients for selected cities:
ASIA AFRICA
The red line represents 0.4 on the GINI coefficient scale
UN‐Habitat, 2009
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Urban Inequalities in Latin America & Caribbean
UN‐Habitat, 2009
Latin American Urban Populations• Brazil and Mexico together are home to ~54% of the region’s urban population
• In Brazil, 34 percent of households are classified as ‘slums’• Of these, 12% lack improved sanitation for wastewater
• The highest proportion of slums in Latin America can be found in Haiti, Guatemala, Nicaragua (C.A.), and Bolivia (S.A.)
• In most of Latin America, access to improved water and improvedsanitation for wastewater is more common than in other parts of the developing world
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UN‐Habitat, 2009
UN‐Habitat, 2009
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UN‐Habitat, 2009
Latin American Urban PopulationsLatin America and the Caribbean have almost completed its urban transition
Urbanization rates are stabilizing and slum growth rates are slowing
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Age‐sex pyramids for slum, non‐slum and rural populations in Brazil
UN‐Habitat, 2009
SLUMSand urban inequalities
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How is a ‘Slum’ defined?• Our text book uses indicators of deprivation based on five conditions:
1. Poor access to improved water
2. Poor access to sanitation
3. Non – durable housing
4. Insufficient living area, and
5. Insecure tenure (lack of ownership)
• It is important to remember that even if it is defined as a ‘slum’, it is a community for the people living there…
Origin of the word, ‘slum’• The word ‘slum’ appeared in London at the beginning of the 19thc, designating, initially, “a room of low repute”
• At the end of the 19thc, the word appears in the Oxford English Dictionary:
• The contemporary use of the word ‘slum’ is often inter‐changed with ‘shanties’, as in ‘shanty‐towns’
• Shanty‐towns are spontaneous settlements that develop in outskirts of towns
• While officially different, ‘shanties’ are now considered by some as a type of slum
“A street, alley, court, etc., situated in a crowded district of a town or
city and inhabited by poor people or a low class or by the very poor;
a number of these streets or courts forming a thickly populated
neighborhood or district where the housed and the conditions of life
are of a squalid and wretched character”
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How is a ‘Slum’ defined?• The term ‘slum’ has loosely been used in the West when referring to housing areas that were once affluent, but have deteriorated
• This is not the same as the definition of ‘slum’ in the non‐western world
• Non‐western urban slums are not simply parallel to ‘poor areas’
• Contemporary slums of the non‐western world are informal settlements where newcomers to the city can find:
• affordable shelter
• enclaves of local culture, and
• support from a social network
• The United Nations (author of our text book) and many at the World Bank argue that slums should be eradicated
• Is that a solution? Is it achievable? Who would this serve most?
How is a ‘Slum’ defined?• Despite the few positives a slum may provide for rural newcomers to the city, slums are characterized by many negatives, such as:
• Poverty
• Illiteracy
• Unemployment (official, taxable employment)
• Informal economies
• Crime
• Drug proliferation
• Disease
• ‘Waste’ collection
• Absence of disaster response and relief
• (fire, police, earth‐moving, etc.)
• Alternatively, it can be argued that these types of urban settlements represent the ultimate in the free‐movement of people, thus representing true democracy
• And that those cities that try to demolish them are totalitarian
What is the best course of action to address these types of settlements?
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• Sub‐Saharan Africa (62.2%) followed by South Asia (42.9) rank the highest in the proportion of urban populations living in slums
• Latin America (27%) is much lower and we can relate this to the region’s demographic transition (as seen in the DTM)
Rio de Janiero, Brazil
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Planning as a response to slums
• Understanding the function in concept, and geography of slums in context is necessary
• Urban Planning techniques include;• Monitoring and predicting of the expansion
• Improvement of existing facilities
• Disaster prevention
• Environmental resource management
• And, if absolutely necessary, relocation of residents to formal housing
• A crucial requirement for effective Urban Planning is to have access to accurate and updated spatial data
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Water
We can’t do without it, but there may not be enough of
it…
World Fresh Water Supply
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Some Water Statistics…• 3.575 million people die each year from water‐related disease
• Poor people living in slums often pay 5‐10 times more per liter of water than wealthy people living in the same city
• An person taking a five‐minute shower uses more water than a typical person in a developing country slum uses in a whole day
Hydrologic/Water cycle
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Urban water cycle• This graphic illustrates the impact of human activity on groundwater. It shows that groundwater is obtained from periurban wellfieldsand urban wells, then used and disposed of as wastewater through pluvial drainage, piped sewage and on‐site sanitation and industrial effluent disposal. It also shows that wastewater is treated and then reused for irrigation, with excess flows re‐entering the aquifers.
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Urban waters supply challenges:
1. Population growth• As population increases, water supply infrastructure need to expand
• This is of high cost to local governments even though in many cases it is not sufficient
• The continued construction of new illegal settlements makes it harder to map and to connect the pipes to the supply network system, that in the end can lead to inadequate management
2. Water Scarcity• Potable water (water fit for drinking) is unevenly distributed globaly
• Many people do not have access to it OR do not have access to standard levels of potable water even where the resource is abundant
• Geographically, disadvanteged populations in developing countries may actually be closer to major water sources, but do not have access to potable water at all
• Ironically, there are people that live in areas where the lack of water creates millions of deaths every year
Urban waters supply challenges:
3. Mis‐guided government policies– Policies meant to promote economic growth sometimes demand water resources that exceed local demand
– Or, lack of investment in the water supply network
– Permitting industrial uses that threaten or destroy water supplies
4. Globalizing of industrial production – where labor is plentiful, but (drinkable) water is not…
5. Privatization of Water– When the provision of water to citizens is no longer a public utility, but a
private enterprise
– AND when the sources of water become privately owned
– More on this next week…
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Areas experiencing depleted water resources
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Water used in production:
• 1 pound of rice: 250 to 650 gallons of water
• 1 pound of wheat: 130 gallons of water
• 1 pound of potatoes: 65 gallons of water
• To grow the feed for a cow to make ¼ pound of hamburger:• 3,000 gallons
• For the cow to fill its udders with a quart of milk:• 500 – 1,000 gallons
• Cheese?• About 650 gallons for a pound of cheddar
Fro
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Water used in production:• Sugar?
• 1 pound takes 400 gallons of water
• Coffee?• 1 pound takes (hold on…) 2,650 gallons (that’s 10 tons!) of water!
• If we turn these numbers into portions for a meal, it’s like this:• 25 gallons for a portion of rice
• 40 gallons for the bread in a sandwich or for toast
• 130 gallons for a two‐egg omelet. Same amount for a tossed salad.
• 265 gallons for a glass of milk
• 400 gallons for ice cream
• 530 gallons for a pork chop
• 800 gallons for a hamburger
• 1,320 gallons for a small beef steak
Fro
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Note: the concept of‘virtual water’ is used for these estimates.
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‘Virtual’ watersimilar to a ‘water footprint’
• Virtual water refers to, in the context of trade, the water used in the production of a good or service – from beginning to end
• It refers to the sum of the water use in the various steps of the production chain
• The Virtual Water Project (with IPhone app)• http://virtualwater.eu/
Water Footprint• A water footprint is conceptually made up of three kinds of water:
– Blue water ‐ the volume of freshwater that evaporated from the global blue water resources (surface water and ground water) to produce the goods and services consumed by the individual or community
– Green water the volume of water evaporated from the global green water resources (rainwater stored in the soil as soil moisture)
– Grey water the volume of polluted water that associates with the production of all goods and services for the individual or community
• The Water Footprint Network– http://www.waterfootprint.org
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Local Urban Stream Management,Water Use, and
Flooding
Poor examples of urban river management (as a result of natural resource planning policy):
Somewhere in Africa(worst case example)
Somewhere in South America(better, but still not good)
Photo Source: ‘Sick Water’ United Nations, 2010
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Better examples of urban river management (as a result of natural resource planning policy):
Columbus, Ohio
San Jose, CA
Photo Source: http://development.columbus.gov
Photo Source: http://visions2200.com
Flow‐channel interplay
• Two (2) facts must be applied when attempting to interpret stream features:
1. Types and magnitudes of stream processes that can be observed on most days may have little or nothing to do with the origins of most channel forms and valley features
2. Through erosion and deposition the stream is continually adjusting its channel and, in turn, its slope, depth, and bed shear stress
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The Changing course of the Mississippi River
• Every 1,000 years or so, rivers change courses due to sediment build‐up and subsequent re‐direction
• The Mississippi’s fresh water discharge is so massive (200.000 to 700.000 ft³/sec) that a plume of fresh water is detectable from outer space, even as it rounds Florida and up to the coast of Georgia.
Stream Components (1)
Thalweg –• (Map) a line, as drawn on a map, connecting points of a valley
• (Border) the middle of the main navigable channel of a waterway that serves as a boundary
‐ (Stream) the deepest part of a stream channel where water velocity is often the fastest within its longitude
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• During low flows (in most streams) water is spatially distributed in a sequence of calm pools linked together by rapid segments called riffles
• Ideally, in streams where we live:• a ‘Run’ is after a riffle and before a pool
• a ‘Glide’ is after a pool and before a riffle
Some streams can be Riffle/Run prevalent,
while others can be Pool/Glide prevalent
• Pools contain fine sediment
• Riffles contain larger particles
Riffle – pool sequence
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Stream ‘Reach’
A unit length of channel type where the same channel type ideally exists for at least twenty bankfull widths (Rosgen)
www.fgmorph.com
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Household Energy Consumption
Urban Energy Consumption varies by Economic Sector
In the global economy, economic activities are separated into four distinct categories:
• Primary Sector: Involves the extraction and production of raw materials• Mining industry / Fishing industry / Timbering industry / Farming industry
• Secondary Sector: Involves the transformation of raw materials into goods adding value to that raw material
• Manufacturing industry / Construction industry / Food Processing industry
• Tertiary Sector: Involves the provision of services to consumers and businesses• Retail Consumer Goods Industry / Tourism Industry / Entertainment Industry
• Quaternary Sector: Involves the research and development needed to produce products from natural resources and the assembly, transmission and processing of information and data
• Financial industry / Education industry / Media industry