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Ecumene: The proportion of earth

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Title: Ecumene: The proportion of earth


1
Ecumene The proportion of earths surface
occupied by permanent human settlement. This is
important because it tells how much of the land
has been built upon and how much land is left for
us to build on.
2
Population Density- the frequency with which
something occurs in space is density
  • Densities help describe the distribution of
    people in comparison to available resources.
  • Arithmetic density measures the total number of
    people living in an area.
  • Physiological density and agricultural density
    show spatial relationships between people and
    resources.

Figure 2.2.3
3
Arithmetic Density- The total number of people
divided by the total land area.  This is what
most people think of as density how many people
per area of land.
  • Population Density
  • Divide population by the land area
  • U.S. 31/sq km
  • India 350/sq km
  • Singapore 7000/sq km
  • Allows comparisons between different regions

Figure 2.2.1
4
Physiological Density- The number of people per
unit of area of arable land, which is land
suitable for agriculture
  • Population supported by arable land
  • More meaningful
  • U.S. 172/sq km
  • Egypt 2580/sq km
  • A measure of food resources and production
    requirements against population needing food
  • Large difference between arithmetic and
    physiological densities can mean significant
    problems

Figure 2.2.3
5
Agricultural Density
  • Ratio of farmers to arable land
  • U.S. 1/sq km
  • Egypt 826/sq Km
  • MDC have lower densities because of technology
    and economics
  • MDC fewer farmers feed more people
  • LDC have more people committed to farming but
    produce less

Figure 2.2.4
6
Carrying capacity This is the population level
that can be supported, given the quantity of
food, habitat, water and other life
infrastructure present.  This is important
because it tells how many people an area will be
able to support. Affects the population and a
countrys or areas ability to support that
population. 
7
Sustainability- providing the best outcomes for
human and natural environments both in the
present and for the futureRelates to development
that meets todays needs without compromising the
ability of future generations to meet their own
needs. 
8
Distribution The arrangement of something across
Earths surface (space). 
  • Population distributions- the arrangement of a
    feature in space is distribution.  Geographers
    identify the three main properties as density,
    concentration, and pattern (Used to describe how
    things and people are distributed)

9
Population
  • More humans alive than in Earths history.
  • 6.75 billion and growing
  • Most live in Less Developed countries
  • Most Developed Countries are growing slowly or
    not at all
  • Over population concerns
  • Not simply numbers
  • Resource needs
  • What is the balance?
  • Population density

10
Population Concentrations
  • Two-thirds inhabitants in four regions
  • Humans avoid harsh environments
  • Sparsely Populated Regions
  • Too dry, wet, cold, or mountainous
  • Poorly suited for agriculture
  • Four Populous Regions
  • Near oceans or rivers
  • Low-lying, fertile soils, temperate

Figure 2.1.1
11
  • Major population concentrations (distributions)
  • -East Asia largest concentration China, Japan,
    North and South Korea (gt1.5 billion people). 
    Ribbon-like extensions of dense population
    (clustered near rivers majority of people are
    farmers)
  • -South Asia second major concentration India,
    Pakistan, Bangladesh, Sri Lanka (1.5 billion). 
    Also ribbon (finger)-like extensions of dense
    population (e.g. Ganges River in India), majority
    are farmers as well.
  • -Europe third major concentration Britain to
    Russia, including Germany, Poland, Ukraine,
    Belarus, Netherlands, Belgium, parts of France,
    northern Italy (700 million).  Ribbon-like
    extension deep into Russia (follow Europes coal
    deposits, not fertile river valleys).  Ribbons
    are concentrated along numerous cities towns
    (due to the Industrial Revolution Germany 85
    urban, UK - gt90).
  • -North America a far fourth east-central US and
    southeastern Canada (lt200 million).  Like Europe,
    much is concentrated in major cities.

12
Population Concentrations (cont.)
Figure 2.1.2
13
Linear growth arithmetic growth increases at a
constant amount per unit time (1, 2, 3, 4, )
14
Exponential growth geometric growth doubles
each population (2, 4, 8, 16, )
15
Doubling time The number of years needed to
double a population, assuming a constant rate of
natural increase. This is important because it
can help project countries population increase
over the years and when its population will
double. It is a projection and not meant to be an
accurate predictor of the future.
16
Population explosion- a sudden increase or burst
in the population in either a certain
geographical area or worldwideOccurred in the
late 18th and early 19th centuries because
several countries moved on to stage 2 of the
DTM.  Can trace factors that lead to these
explosions.Population structure (composition or
distribution) (Population pyramid) is two
back-to-back bar graphs, one showing the number
of males and one showing females in a particular
population in five-year age groups.  This is
important because you can tell from the age
distribution important characteristic of a
country, whether high guest worker population,
they just had a war or a deadly disease and
more. 
17
Population Structure- (Population pyramid) is two
back-to-back bar graphs, one showing the number
of males and one showing females in a particular
population in five-year age groups.  This is
important because you can tell from the age
distribution important characteristic of a
country, whether high guest worker population,
they just had a war or a deadly disease and more
  • Individual women influence a countrys birth rate
  • Infants and older people influence the death rate
  • Patterns of births and deaths result in
    distinctive age structures or population pyramids

Figure 2.4.2
18
  • Cohort Population of various age categories in a
    population pyramid.  This is important because
    this can tell what state this country it is
    whether in Stage 3 or Stage 5 in the demographic
    transition model. 
  • Baby Boom people born in the US between 1946 and
    1964 this post-war era allowed for better
    education, employment, peace and prosperity -
    increasing higher rates of both marriage and
    fertility.
  • Baby Bust period in the US during the 1960s and
    1970s when fertility rates dropped as many female
    baby boomers sought higher levels of education
    and jobs, marrying later in life

19
  • Generation X people born in the US between 1965
    and 1980 will have the burden of supporting the
    Baby Boom cohort as they head into retirement.
  • Generation Y people born between 1980 and 2001
    also referred to as "Echo Boomers" (many are the
    offspring of Baby Boomers).

20
  • Demography geographic study of population

21
  • Natural increase births minus deaths in a given
    population.

22
Natural Increase Rate- the percentage by which a
population grows in a year.  CBR-CDR
NIR (excludes migration)
  • The percentage by which population grows in a
    year
  • Excludes migration
  • World NIR for the past 10 years has been 1.2 or
    1.2
  • 1963 NIR peaked at 2.2
  • NIR of most LDC exceeds 2.0
  • Most people live in countries least able to
    maintain them
  • Doubling Time
  • 1.254 years
  • 1.0 70 years
  • 80 million people added each year

Figure 2.3.1
23
Crude Birth Rate- number of live births per year
per 1,000 people
  • Total live births per 1000 people each year
  • CBR of 20 means 20 babies/1000 people in a year
  • As with NIRs the highest CBRs are highest
    (near 40) in sub-Saharan
  • Africa and lowest in Europe (lt10) U.S. 14

Figure 2.3.2
24
Declining Birth Rates
  • Lowered birth rate through economic development
  • Contraception
  • More recently birth rate has been decreasing
  • Recent decline in NIR has resulted from lower
    birth rates

Figure 2.7.1
25
Lowering Birth Rates Through Economic Development
  • Education and health-care
  • Educated women control their lives
  • Informed choices
  • Infant Mortality Rates decrease

Figure 2.7.3
26
Lowering Birth Rates Through Contraception
  • Diffusing of modern contraceptive methods
  • Family-planning programs
  • LDC contraceptive supply issues
  • Children as status
  • Political and religious issues

Figure 2.7.4
27
Crude Death Rate- number of deaths per year per
1,000 people
  • Total deaths in a year for each 1000 living
  • NIR CBR CDR
  • 15 20 5 or 1.5
  • CDR varies regionally and in combination
  • Denmark has a higher CDR than an LDC
  • U.S. has a higher CDR than Mexico
  • The reason is population differences due to
    demographic transition

Figure 2.3.3
28
Mortality There are two useful ways to measure
mortality infant mortality rate and life
expectancy.
  • Child mortality rate annual number of deaths of
    children under the age of 5, compared with total
    live births (also calculated as number of deaths
    per 1,000 births).
  • Maternal mortality rate annual number of deaths
    of women during childbirth per 1,000 women.

29
Infant Mortality Rate- The annual number of
deaths of infants under one year of age, compared
with total live births. Its is expressed as the
annual number of deaths among infants among
infants per 1000 births rather than a percentage.
This is important because it reflects the
healthcare system and tells how developed a
country is, if they have a high IMR they are an
LDC and if it is low they are an MDC. 
  • Deaths of infants under 1 year of age
  • Deaths per 1000 births
  • Highest rates in LDC
  • Lowest in MDC
  • Relation to health care system and minorities

Figure 2.4.3
30
Life Expectancy
  • Average number of years a newborn can expect to
    live
  • Related to countrys wealth
  • MDCs 70
  • LDCs low 40s

Figure 2.4.4
31
Total Fertility Rate (TFR) average number of
children born to a woman during her childbearing
years (expressed as children per woman).
  • TFR the average number of children a woman will
    have between 15 and 49
  • World as a whole 2.7
  • Sub-Saharan Africa 6
  • Europe lt2
  • U.S. citizens 1.5
  • U.S. total 2.1
  • TFR predictive of change

Figure 2.4.1
32
Total fertility rate (TFR)-
  • In the U.S its below 2.1 in much of Africa it is
    above 4, if South America is between 2 and 3, in
    Europe it is below 2.1, in China and Russia it is
    below 2.1, and in much of the Middle East it is
    above 4.  This is important because its shows how
    many kids a mother is having

33
  • Dependency ratio The number of people who are
    too young or too old to work compared to the
    number of people in their productive years. This
    is important because this tells how many people
    each worker supports.  For example the larger
    population of dependents, the greater financial
    burden on those who are working to support those
    who cannot. 

34
Young and Old
  • Age distribution is critical
  • Dependence ratio number of people too young or
    too old to work
  • More dependants greater financial burden (lt14 or
    gt65)
  • Graying - increased costs

Figure 2.4.5
35
  • Demographic equation The formula that calculates
    population change. The formula finds the increase
    (or decrease) in a population. The formula is
    found by doing births minus deaths plus (or
    minus) net migration. This is important because
    it helps to determine which stage in the
    demographic transition model a country is in. 

36
  • Demographic Transition model Has 4 steps. Stage
    1 is low growth (low stationary), Stage 2 is High
    Growth (early expanding), Stage 3 is Moderate
    Growth (late expanding), and Stage 4 is Low
    Growth (low stationary), and Stage 5 although not
    officially a stage is a possible stage that
    includes zero or negative population growth. 
    This is important because this is the way our
    country and others countries around the world are
    transformed from a less developed country to a
    more developed country.  
  •  

37
The Demographic Transition
  • Every country is in one of the
  • four stages
  • Process of change in population structure
    (Demographic Transition)

Stage 1 Very high CBR
Very High CDR
Very Low NIR
Stage 2 Still high CBR
Rapidly declining CDR
Very high NIR
Stage 3 Rapidly declining CBR
Moderately declining CDR
Moderate NIR
Stage 4 Very low CBR
Low, slightly increasing CDR
0 or negative NIR
38
The Demographic Transition (Cont.)
  • Denmark Stage 4
  • Cape Verde Stage 2

Chile Stage 3
2.5.3 Population and Demographic Transition p37
Figure 2.5.3
39
  • Demographic momentum this is the tendency for
    growing population to continue growing after a
    fertility decline because of their young age
    distribution.  This is important because once
    this happens a country moves to a different stage
    in the demographic transition model. 

40
  • Demographic regions Cape Verde is in Stage 2
    (High Growth), Chile is in Stage 3 (Moderate
    Growth), and Denmark is in Stage 4 (Low Growth). 
    This is important because it shows how different
    parts of the world are in different stages of the
    demographic transition.

41
The Epidemiologic Transition
  • Distinctive causes of death
  • Leading causes shift through demographic
    transition

Stage 1 Pestilence and Famine Pestilence and Famine
Stage 2 Receding Pandemics Receding Pandemics
Stage 3 Degenerative and Human-created Diseases Degenerative and Human-created Diseases
Stage 4 Delayed Degenerative Diseases Delayed Degenerative Diseases
Stage 5 Possible Reemergence of Infectious Diseases Possible Reemergence of Infectious Diseases
Evolution
Poverty
Travel
Figure 2.8.2
42
  • J-curve This is when the projection population
    show exponential growth sometimes shape as a
    j-curve.  This is important because if the
    population grows exponential our resource use
    will go up exponential and so will our use as
    well as a greater demand for food and more. 
  •  

43
  • S-curve- traces the cyclical movement upwards and
    downwards in a graph. So named for its shape as
    the letter "s"
  • Relates to growth and decline in the natural
    increase.

44
  • Overpopulation- relationship between the number
    of people on Earth, and the availability of
    resources
  • Problems result when an areas population exceeds
    the capacity of the environment to support them
    at an acceptable standard of living. 
  • Underpopulation- it is the opposition to
    overpopulation and refers to a sharp drop or
    decrease in a regions population
  • Unlike overpopulation, it does not refer to
    resources but to having enough people to support
    the local economic system.  If there are not
    enough tax payers, then the area cannot
    continue. 

45
Stationary population level (SPL) when the crude
birth rate equals the crude death rate and the
natural increase rate approaches zero. (aka Zero
population growth Often applied to countries in
stage 4 of the demographic transition model) 
46
  • Population theorists
  • -Thomas Malthus food production linear human
    reproduction geometric despite natural checks
    (famine, disease) will always be
    overpopulation he brought up the point that we
    may be outrunning our supplies because of our
    exponentially growing population. 
  • Neo-malthusian- theory that builds upon Malthus
    thoughts on overpopulation.  Takes into count two
    factors that Malthus did not population growth
    in LDCs, and outstripping of resources other
    than food
  • Recognizes that population growth in LDCs is
    from the transfer of medical talents from MDCs
    but not the wealth that would provide food and
    resources

47
Malthuss Grim Forecast
  • Population would increase faster than resources
    (1798)
  • Validity questioned
  • Population increase geometrically
  • Food supply increase arithmetically
  • Supporters
  • 18th century few stage 2 countries. Did not
    anticipate LDC growth.
  • Neo-Malthusians population outstripping
    resources not just food

Figure 2.6.1
48
Malthuss Grim Forecast (Cont.)
  • Malthuss Critics
  • Larger population could stimulate development and
    more food
  • Social welfare problems result from unjust social
    and economic institutions
  • World possesses sufficient resources if shared
  • Some LDC leaders desire high population growth
  • Some MDC viewed as preventing growth in LDCs
  • Theory and Reality
  • Globally, recently conditions have not supported
    Malthuss theory
  • Population and food have consistently grown
  • Food production has increased
  • Distribution of wealth may be the problem
  • Population growth has been lower than predicted
  • Cultural, economic and technology change impacts

49
  • -Boserup human growth stimulates agricultural
    intensification (Malthus upside-down)
  • -Marx anti-capitalist lack of food is due to
    unequal distribution human growth is not a
    problem
  • -Cornucopian theory Earth has an abundance of
    resources can never be used up

50
  • Migration Patterns (immigration into a region
    emigration out of a region)
  • -Intercontinental- Permanent movement from one
    country to a different country on the same
    continent.
  • -Interregional- Permanent movement from one
    region of the country to another. 
  • -Rural-Urban- Permanent movement from suburbs and
    rural area to the urban city area. 

51
  • Laws of migration 1885 Ernst Ravenstein
    (studied internal migration in England)
  • 1.     net migration amounts to a fraction of the
    gross migration
  • 2.     the majority of migrants move a short
    distance
  • 3.     migrants who move longer distances tend to
    choose big cities
  • 4.     urban residents are less migratory than
    inhabitants of rural areas
  • 5.     families are less likely to make
    international moves than young adults

52
  • Gravity Model (Ravenstein) Predicts that the
    optimal location of a service is directly related
    to the number of people in the area and inversely
    related to the distance people must travel to
    access it. 

53
  • Push factors incentives for people to leave a
    place (e.g., harsh climate, economic recession,
    political turmoil)

54
  • Pull factors attractions that draw migrants to a
    place (pleasant climate, employment, education)

55
  • Catalysts of migration many exist such as
    economic conditions, political circumstances,
    armed conflict civil war, environmental
    conditions, culture and traditions, technological
    advances, flow of information (through
    technology)

56
  • Friction of Distance- is based on the notion that
    distance usually requires some amount of effort,
    money, and/or energy to overcome. Because of this
    "friction," spatial interactions will tend to
    take place more often over shorter distances
    quantity of interaction will decline with
    distance.

57
  • Distance Decay- The diminishing in importance
    and eventual disappearance of a phenomenon with
    increasing distance from its origin.  Typically,
    the farther away one group is from another, the
    less likely the two groups are to interact. 
    (Electronic devices such as the internet and
    e-mail have aided in eliminating barriers to
    interaction between people who are far from each
    other.

58
  • Step migration migration to a destination that
    occurs in stages (e.g., from farm to nearby
    village and later to town and city)
  • Chain migration migration event in which
    individuals follow the migratory path of
    preceding friends or family to an existing
    community (initial migration created a chain
    reaction)  Can be seen from Mexico to the United
    States when guest workers set up homes and make
    money for their family to follow them. 
  • Intervening opportunity the presence of a nearer
    opportunity that greatly diminishes the
    attractiveness of sites farther away
  • Voluntary migration movement in which people
    relocate in response to perceived opportunity)
  • Forced Migration People removed from their
    countries and forced to live in other countries
    because of war, natural disaster, and government.
     (Atlantic Slave Trade, Jewish Diaspora)

59
Reasons to Migrate
  • Push and pull factors
  • Most migration for economic reasons
  • E.G. Ravensteins migration laws
  • Reasons economic
  • push and pull
  • Characteristics of migrants
  • Distance of migration
  • Resources and industry attract
  • Perception of economic plenty

Figure 3.2.4
60
Cultural Push and Pull Factors
  • Forced migration between countries
  • Slavery
  • Political instability
  • New state boundaries
  • and ethnicity
  • War
  • Refugees

Figure 3.1.2
61
Environmental Push and Pull Factors
  • Physically attractive regions
  • Mountains
  • Sea sides
  • Warm climates
  • Hazardous regions
  • Water too much or too little
  • Floodplains
  • Storms
  • Cant sustain human life

62
Characteristics of Migrants
  • Most long-distance migrants are male
  • Migrant families with children are increasing
  • Increasing female migration social and status
    changes in home country
  • Family status
  • 40 male ages 25 39
  • 16 Children under 15
  • 5 over 65

Figure 3.2.2
63
Global Migration Patterns
  • Most international migration is from LDCs to MDCs
  • United States leading destination
  • Most migrants relocate short distances within the
    same country
  • Wilbur Zelinsky Migration Transition
  • Social changes comparable to demographic
    transition
  • High daily or seasonal mobility related to stages
    of development

64
Immigration by Country
Figure 3.3.2
65
Guest Workers
  • Guest workers migrate from LDCs to Europe and the
    Middle East
  • Low-paying unskilled jobs locals dont want
  • Temporary, time-contract workers with
    restrictions
  • Significant numbers, many from former colonies
  • Both economies gain host country gets low-end
    workers and home country reduces unemployment
    rate and foreign currency to stimulate local
    economy

66
Time-Contract Workers
  • 19th century millions of Asians contracted to
    work for fixed periods
  • Built railroads, mining plantations
  • Many chose to remain in the new country
  • 33 million ethnic Chinese live in other countries
  • Illegal immigration on the increase
  • Reduced pay but higher than at home

Figure 3.4.5
67
Migration to the Unites States
  • Undocumented U.S. Immigrants
  • Changing Origin of U.S. Immigrants
  • U.S. Immigration Patterns

Figure 3.5.3
68
Changing Origin of U.S. Immigrants
  • Three main eras of immigration
  • 17th and 18th centuries
  • Mid 19th to early 20th centuries
  • Late 20th and early 21st centuries

Source of migrants changed in each era
69
Migration to the United States by Region of
Origin
Figure 3.5.2
70
U.S. Immigration Patterns
  • Restrictive Quota Laws
  • Immigration not uniform
  • Origins change but economic push factors at home
    drove immigration
  • Quota Act 1921 and National Origins Act 1924
    established quotas
  • Significant prejudice toward new arrivals
  • Immigration Act of 1965
  • Applicants exceed quotas
  • Refugees and family members are special cases
  • Clusters of immigrants in the U.S.

Figure 3.6.1
Figure 3.6.3
71
Destination of Immigrants by Source and U.S.
States to the End of 2007
Figure 3.6.1
72
Undocumented U.S. Immigrants
  • Legal documentation
  • Lack of policy agreement
  • Primarily for work
  • Students and tourists over staying
  • Slip across the borders
  • Numbers vary widely in the millions
  • There are jobs lower pay
  • Log, broken border, poor maps
  • False papers
  • Americans, divided, want something done

Figure 3.7.2
73
Interregional Migration
  • Opens new regions for development
  • Settled the western United States
  • Cluster population due to trade
  • Terrain obstructions
  • Advances in
  • agricultural technology
  • Railroads

Figure 3.8.2
74
Interregional Migration (Cont.)
  • Other Countries
  • Russia Resources and Industry state controlled
  • Brazil From coastal cities to the interior
    Brasilia
  • Indonesia Paid to move to less populated
    islands
  • India Permits and
  • ethnic protection

Figure 3.8.3
75
Intraregional Migration
  • Traditionally rural to urban areas
  • MDCs most migration is from cities to suburbs
  • 20 million migrants a year
  • Work and housing
  • Counterurbanization
  • Central city population decline
  • Social- not jobs related
  • Homes
  • Land conversion

Figure 3.9.1
76
Reverse Migration
  • Some MDCs seeing migration back to cities
  • Lifestyle reasons
  • Work in cities
  • Inter-city and cultural draws
  • Technology and communications
  • Transportation

Figure 3.9.4
77
  • Counter migration migration back to an original
    area in which people had left (e.g., migration
    increases after natural disasters, yet many
    eventually return after a time)
  • Cyclic movement movement that has a closed route
    and is repeated annually or seasonally (e.g.,
    activity (action) space space within which
    daily activity occurs commuting, seasonal,
    nomadism)
  • Periodic movement movement that involves
    temporary, recurrent relocation (e.g., military
    service, migrant workers, college attendance,
    transhumance movement of pastoralists and their
    livestock between highland and lowland pastures)
  • Migratory a change in residence intended to be
    permanent

78
  • Refugees people who leave their homes because
    they are forced out (but not because they are
    officially relocated (Nazis forcing Jews into
    ghettoes) or enslaved.  Most refugees 1) move
    without any more tangible property than what they
    can carry or transport with them 2) make their
    first step on foot, by bicycle, wagon, or open
    boat and 3) move without the official documents
    that accompany channeled migration.
  • -internal displaced within their own countries
  • -international crossed an international boundary
    during dislocation seeking asylum in a different
    country

79
Population policies typically sponsored by
governments
  • -PRO-NATALIST/ Expansive encourage large
    families and raise the rate of population growth
    (e.g., USSR under Stalin and China under Mao
    Zedong)
  • -ANTI-NATALIST/Restrictive reduce the rate of
    natural increase (e.g., India promoted
    sterilization, now has focused on education,
    advertising, and family planning in China the
    One-Child policy since 1978)

80
  • -Eugenic favor one racial sector over others
    (e.g., Japan, US up until the civil rights
    movement (1960s), Nazis are an extreme example of
    eugenics)

81
  • Census tract areal unit that best approximates a
    neighborhood in size through small county
    subdivisions
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