World food and pop exam 1

Why our population has grown
so quickly?

Humans have the ability to expand into all climate
zones and habitats
 Modern agriculture has allowed us to produce food
very efficiently and in large quantities
 Death rates decreased because of improved
sanitation and healthcare (biggest influence)

What is the current population growth?

Around 1.7% per year (and slowing). Most of this growth
happens in developing countries.

Factors affecting growth

Births, Deaths, Immigration, Emigration, and fertility rates

What factors affect birth and fertility rates?

Cost of raising and educating children
 Urbanization
 Infant deaths
 Education for women
 Marrying age
 Access to contraceptives

What factors affect death rates?

 Access to nutrition, medical care, clean water
 Community support for elders
 Increased life expectancy
 Usually higher for women
 Decrease in infant mortality

Factors affecting Migration (immigration and emigration)

Net migration rate ( difference between immigration and
emigration per 1000 people in a given year (only effects
individual countries)
 Better jobs and economic improvement
 Religious, ethnic, or political conflicts
 Lack of access to basic needs (food, water, etc.)
 Environmental refugees

Population Pyramids

Graph (histogram) that allows us to see the population
growth within a country broken down by age groups and
gender
 horizontal axis: gender
 male: left-hand female: right-hand
 absolute number of people or %
 vertical axis: age
 5-year or 10-year age groups
 Ages categorized as...
 Pre-reproductive: ages 0-14
 Reproductive: ages 15-44
 Post-reproductive: ages 44+

Classify population pyramids

Rapidly Growing: large amounts of people in the pre-
reproductive and reproductive years
 Very large bottom of the pyramid
 Growing Slowly: more individuals in the pre-
reproductive and reproductive years
 Bottom of pyramid is slightly larger than the rest
 Stable (zero population growth): population is evenly
distributed throughout age groups
 Pyramid is relatively even top to bottom
 Declining (negative growth): more individuals in the
post-reproductive age groups
 Bottom of pyramid is smaller than the top

Demographic Transition: 5 stages

Stage 1—Birth and death rates are both high
 Stage 2—Death rates fall; birth rates remain high; growth rate
rises. “Developing Countries” Much of Africa today Wide base
 Stage 3—Birth rates fall as standard of living rises; growth rate
falls and continued decline of death rates; Wide Middle ; “moderately developed countries” Mexico today.

Economic change: urbanization ( have fewer children)
 Stage 4 and 5—Growth rate continues to fall to zero or to a
negative rate, low birth and rising but low death rates; 4: slender and 5 : narrow base; several Europe countries

Solutions for slowing population growth

• Economic development

• reduction of poverty

• education

• Family planning: reproductive health care

• empowering women

Problems with a growing population

graying of a population” (Japan)
 Characteristic of highly developed countries
 Women choosing not to have children..pursue career instead
 who will care for the elders?
 income to provide for social services
 economic impacts (smaller workforce)
 some countries providing incentives to have more
children (Europe)
 may be balanced out with a large number of
immigrants

Land uses

• Residential

• Commercial

• Industrial

• Institutional

• Transportation

• Agricultural

• Park and Green Spaces

Agricultural Land

US has 350 million acres of prime farm land

Much is being overtaken by suburban sprawl: parking lots, housing, developments, and shopping malls

U.S. Agriculture:

• Industrialization

• Specialization

• Rapid technological changes

• Internationalization

• Changing consumer tastes & preferences

• Changing government policies

Changes In Farm and Agribusiness Firms

Old concept: produce and sell commodities, sell product, give away service, tradition, art, staple products, family farming, independence, stability, US primary world food producer, farm income lower.

New Concept: industrialized farm, sell service, give away product, innovation, science, specialty products, industrializing farming, interdependent, high risk, international comp. , farm income comparable.

Land problems

• Erosion

• Deforestation

• rapid urbanization

• climate change

Landforms

Features that make up the Earths surface

Archipelago

A group or chain of islands in a large body of water

Bay

A body of water that is partly enclosed by land

Gulf

A part of the ocean (or sea) that is partly surrounded by land (usually largers than a bay)

Isthmus

A narrow strip of land connecting two larger landmasses. Has water on 2 sides

Mountain

A natural elevations of the earths surface

Ocean

A large body of salt water that surrounds a continent. Oceans cover more then 2/3rds of Earths Surface

Peninsula

Land that is surrounded by water on three sides

Plain

Flat lands that only have small changes in elevation

Plateau

A large, flat area of land that is higher than the surrounding land.

River

A large, flowing body of water that usually empties into a sea or ocean

Sea

A large body of salty water that is often connected to an ocean. A sea may be partly or completely surrounded by land.

Valley

A low place between mountains

What cause soil erosion?

Removing plant cover by burning pasture or felling trees.

• having to many animal on the land

• bad cultivation practices

• wind

• frost

• rain and water runoff

• extreme climatic effects

Erosion by wind

Dust storm; carrying loose unprotected soil into cities

Erosion causes by animals

Overgrazing; leads to the extinction of indigenous plant and animal species, soil erosion, and eventual desertification that renders once-fertile soil

People affecting erosion

construction sites; residential and commercial

traditional plowing

deforestation

What can we do about soil erosion?

Contour farming, no-till farming, terracing, wind breaks/barriers, grassed waterways, soil mats during construction, re-seeding and planting trees, covering with mulch, spraying water to prevent wind erosion, retaining walls

What is deforestation?

Cutting, clearing, cleaning, and removal of rainforest or related ecosystem into less bio-diverse ecosystem such as pasture, cropland, or plantation.

• Permanent destruction of indigenous forest and woodlands

Importance of forest

removing CO2 from the air, photosynthesis, carbon sink ( takes CO2 and stores it)

Types of deforestation

 1. Natural reasons (i.e volcanic eruption) these
reasons are only occur for a small fraction
 ii) Land clearing to prepare for crops to be
planted
 iii) Commercial logging and timber harvests
 iv) Slash and burn forest cutting for subsistence
farming

Causes of deforestation

• logging

• mining

• oil/gas extraction

• cattle ranching

• agriculture: cash crops

• Local, National, and International factors:
  development, land titles, government subsidies to
  attract corporations into developing countries,
  trade agreements (NAFTA, CAFTA), civil wars,
  debt, lack of resources, and lack of law
  enforcement.

Effects of deforestation

Environmental impact:

Habitat fragmentation( disturbs animal habitat and may force them to enter a habitat which is already occupied)

Soil erosion

Climate change one of the main causes (more CO2 released into atmosphere); huge impact on global warming; 20% of greenhouse gas emissions

Pollution

Social impacts of deforestation

Social conflicts and struggles over land and
natural resources.
 Conflicts over racial and ethnic rights.
 Poisoning from oil and mining waste.
 Economic uncertainty (price fluctuations and
high interest rates on outstanding
international loans with The World Bank and
International Monetary Fund.

Solutions to deforestation

Corporations/Markets
 They can use forest products wisely
 Implement paper saving laws and policies
 Politics
 Politicians can implement national laws to help
achieve zero deforestation
 Consumer Power
 As a consumer we can pressure the companies
to implement paper saving laws and policies and
be more eco friendly

List of largest rainforest’s

 Amazon basin of South America
 Congo river basin of Central Africa
 S.E. Asia
 New Guinea
 Madagascar

What is urbanization?

The growth of cities, brought about by a population shift from rural areas and small communities to large ones, and the change from a largely agricultural economy to an industrial one

Causes of urbanization

A city grows through natural increase - the excess of births over deaths and the in-migration of people from rural areas

• MDCS and LDCs differ in the way in which urbanization is occurring

• Economic development

• Industrial revolution
   Job/employment opportunities
   Availability of easy Transportation
   Agglomeration economies
   Political, cultural and social influences

much of urban migration is driven by rural pop. desire for the advantages offered in urban areas

Megacities

As the population increases, more people will live in
large cities. Many people will live in the growinglarge cities. Many people will live in the growing
number of cities with over 10 million habitantsnumber of cities with over 10 million habitants
known asknown as megacitiesmegacities. shows,.

Urbanization problems

• Urban sprawl

• overcrowding

• unemployment and under employment

• shortage of residential housing

• transportation

• water

• sewage/trash disposal issues

• poverty/urban crime

• Competition on limited resources

• sanitation

• consume more food and durable goods

• energy consumption

Remedies for the problems of urbanization

 Urban planning, urban infrastructure, urban
development.
 Solid waste management/wastewater treatment
 Law and order situation
 Public transport – traffic congestion
 Improve physical and social environments
 Develop the economy of villages/small scale
industries viable

Things that can cause the climate to change

1. Natural variations

2. Volcanic Eruptions

3. Human activity

Changes: climate change

• Earth has warmed ( increased by 0.74 C)

• Rainfall patterns have changed

• Global sea levels have risen

• More extreme weather ( tropical storms and hurricanes increase)

Climate change is affecting our lives by

• health impacts

• agriculture

• forest impacts

• water resources

• wildlife

• costal areas

Must change for climate change

There is need to adopt mitigation measures to reduce greenhouse gas emissions at
their source or enhance their removal from the atmosphere. These should include using
renewable energy and planting more trees.

• Adaption : including technological, behavioral, and managerial

What is Pollution?

When harmful substances contaminate the environment

• any undesirable change in the physical, chemical, biological characterisitc’s of any component of the environment which can cause harm to life and property.

Air pollution

An atmospheric condition in which certain substances (including normal constituents in excess) are present in concentrations which can cause undesirable effects on man and his environment

• In the form of gases ( Nox, Sox, CO, VOC) dust, smoke, fumes, radioactive

Sources of air pollution

Natural: Volcanic eruptions, forest fires, pollen, biological decay, etc.

Anthropogenic: thermal power plants, vehicular emissions, industrial units

Primary pollutants v secondary

Primary: are emitted directly from the point source

Secondary: formed by interaction of primary pollutants

Indoor air pollution

Many people spend large portion of time indoors - as much as
80-90% of their lives.
 We work, study, eat, drink and sleep in enclosed environments
where air circulation may be restricted
 Children, women more exposed to risk
 Radon gas
 Burning of dung cakes for fuel, wood, kerosene
 Incomplete combustion produces CO
 Cigarette smoke

Control of Air pollution

Proper air pollution control devices in industries
 Using low sulphur coal
 Regular engine tune up, replacement of old more polluting
vehicles
 Using mass transport system, bicycles etc
 Shifting to less polluting fuels
 Planting more trees

Pollution control devices

cyclone separator and bag house filter

Water pollution

The Contamination of water with undesirable
substances which make it unfit for usage is termed
water Pollution.