Presentation on theme: "Sustainability: Global Population – History, Changes, Areas of Crisis, Causes, and the Future"— Presentation transcript:
Sustainability: Global Population – History, Changes, Areas of Crisis, Causes, and the Future http://www.lib.utexas.edu/maps/world_maps/world_rel_803005AI_2003.jpg
Global Population: http://www.worldpopulationbalance.org/images/exponential.gif Global population is exponentially increasing: What does that mean? Exponential growth means that it takes fewer and fewer years for the population to grow by the same amount.
History of Population Growth: What are some of the reasons that the world’s population has increased so much? 1.Sanitation Improvements: - In the early 1800s, soap use greatly increased. - By the mid to late 1800s, municipal sanitation systems were much more common. - Improved sanitation results in fewer people dying from infectious diseases. http://www.knowitall.org/techteam/teams/marion/websites /cherry/Images/soap.jpg Before municipal sewer systems, many communities dumped their sewage into nearby rivers (where their drinking water also came from) or even directly into centers of streets (where it drained to nearby water sources) ! For example, in the 1860s, London built an extensive sewer system. http://www.bbc.co.uk/england/sevenwonders/lo ndon/i/man_made/sewer302.jpg
Changes in population continued… 2. Medical Improvements: - Improving sanitation practices in the medical community - New medicines – particularly antibiotics and vaccinations - These improvements have resulted in fewer infant and children deaths as well as a longer average lifespan around most of the world. Before improvements in sanitary conditions in hospitals, people were very likely to die from other infectious diseases transmitted there. http://www.biotechnologyonline.gov.au/images/co ntentpages/antibiotics.jpg Before antibiotics, minor infections could easily kill people. http://www.rrojasdatabank.org/figure65.gif
Changes in population continued… 3. Agricultural Changes: - Greatly increased crop production per acre from the mid 1940s to early 1980s. - Crop production is no longer increasing – there are problems with soil, water and plant diseases using current farming practices. - Overall, many more people are fed on smaller pieces of farmland compared to 100 years ago. http://www.tox.ncsu.edu/photos/spray_groundrig_resize.jpg http://agronomyday.cropsci.uiuc.edu/2003/liquid_ manure/robert-fig-1.gif Increased use of pesticides and fertilizers as well as new equipment allowed for greater crop density Many fertilizers are made from petroleum and so are not really sustainable and are increasing in cost. Large-scale homogenous agriculture puts plants at great risk for death from diseases and pests. For example, today the average acre of agriculture in the U.S. is producing 5-6 times more food than it did in 1940. http://www.precisiongps.com/images/Manure%20Pics/c orn%20field.jpg
Changes in population continued… Worldwide – child mortality is much lower and life expectancy is much greater than in the past. However, not all parts of the world have low mortality or long life expectancy.
http://www.fi.edu/guide/hughes/images/pop-1a.jpg The World’s population is unevenly distributed.
Uneven distribution of population: Developing countries are experiencing considerably faster population increases compared to developed countries. Developing Countries have a greater fertility rate for women http://www.globalchange.umich.edu/globalchange2/current/lectures/human_pop/human_pop.html
Uneven distribution of population… http://www.ablueplanet.org/images/terra.jpg In most developing countries, women are 2 nd class citizens. Women do not have the same opportunities as men in: Health care Education Employment Legal rights Women’s disadvantage begins immediately: Boys get more food than girls. Boys are many times more likely to get medical care than girls. Boys have much greater chance of attending school. As a result, women must find economic security through marriage. Once married, women need at least one son (and, ideally more) to provide for future security. Strong connection between education and fertility – when women have educational (and employment) opportunities, they have fewer children. http://www.unesco.org/education/tlsf/TLSF/theme_c/mod12/img/fig_femlit_sml.gif
Uneven distribution of population… Vastly differing access to family planning and birth control options in the developed and developing world. More than 500,000 women die every year from pregnancy or childbirth: - Primarily in developing countries - Often associated with poor health and very little time between pregnancies - Women (and couples) in developing countries often have no access to birth control even when they want it http://www.ispub.com/xml/journals/ijh/vol3n2/reprod-fig1.jpg http://www.who.int/reproductive-health/publications/health_benefits_family_planning/FPP_95_11_chapter1.en.html
Why is increasing population such a concern? Human suffering: Poverty : 3 billion people worldwide live in extreme poverty (on less than $2/day). Sanitation : More than 1 billion people do not have access to clean (and safe) drinking water. http://www.worldwater.org/drinkwat.gif
The concern of increasing population… Human Suffering: Hunger and malnourishment : Thousands of children die everyday from lack of food and poor nutrition. War : Many conflicts worldwide are directly or indirectly caused by too many people wanting a limited number of local resources. Millions of people are forced to become refuges every year. http://www.unicef.org/sowc05/english/map3.html
The concern of increasing population… Environmental Damage: Pollution of soil, water and air : Areas under strain from higher populations often have poor land, water and air quality. Few environmental protection plans exist in developing countries. http://www.waterencyclopedia.com/images/wsci_03_img0425.jpg
The concern of increasing population… High population does not mean high consumption: The majority of the World’s population lives in developing countries. However, the majority of the World’s resources are consumed in developed countries. As developing countries gain technology and industrialization, their citizens will begin (and are beginning) to use more resources. Projected Coal Plants: http://www.naturalhistorymag.com/0506/images/0506feature_diagram2.jpg
Population Density: earthtrends.wri.org/updates/node/61 Current World Population = 6.7 billion people