CIE Geography A-Level 4: Population Detailed Notes PDF

CIE Geography A-level 4: Population Detailed Notes This work by PMT Education is licensed under https://bit.ly/pmt-cc https://bit.ly/pmt-edu-cc CC BY-NC-ND 4.0...

CIE Geography A-level 4: Population Detailed Notes This work by PMT Education is licensed under https://bit.ly/pmt-cc https://bit.ly/pmt-edu-cc CC BY-NC-ND 4.0 https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc Understanding Population Population is the amount of people in a defined area, e.g. the population of the world is currently 7.6 billion (May 2018). Population can be measured in different ways: Key Population Parameters A parameter is a measurable factor. Population parameters are different ways in which the population is measured, and these are very useful to gain some insight into the characteristics of a population. Distribution Density How a population is spread globally or Measurement of population per unit area, regionally. e.g. population per km2. Numbers Change The amount of people in a defined area Increases and decreases in population over (population) e.g. a town, a region, or a a period of time. country. Natural Increase Natural population change is affected by multiple factors influencing the total population of an area: Birth rate: Number of live births per 1000 of the population per year. Death (mortality) rate: Number of deaths per 1000 of the population per year. Infant mortality rate: Number of deaths of infants under the age of 1 per 1000 of the live births per year. Total fertility rate: The average number of children a mother will birth in her reproductive age. Natural increase rate: % change (in a year), calculated by the birth rate subtracted by the death rate. If birth rates exceed death rates, % change is positive, if death rates exceed birth rates, % change is negative. https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc Health, Mortality, and Morbidity Health, mortality, and morbidity can be used as indicators of a population’s development. Mortality can be numerically measured by mortality rate (number of deaths over time, per unit of population - usually per 1000) and morbidity can be measured by disease incidence or prevalence. Health can be measured using a range of measures, including mortality and morbidity rates. Mortality rates are greatly affected by morbidity (although mortality is also affected by war, genocide and other unnatural causes of death). Patterns of Mortality Mortality rates do vary throughout the world, and provide some indication of the socioeconomic status of a region/country. Crude death rates are highest in all but Northern Africa - a low income region - but are also high in Russia and Eastern Europe. Mortality is particularly low in Central America and the Middle East. Infant mortality (the amount of infants that die per 1000 births) is another indicator of mortality, and perhaps a better indicator of the socioeconomics of a region. Infant mortality is highest in Africa, as well as Pakistan, Afghanistan, and Laos. Infant mortality rates are usually lower in high income, developed countries, such as in the regions of Europe and North America. The map to the right shows infant mortality rates per country, 2017. Source:https://data.worldbank.org/indicator/SP.DYN. IMRT.IN?view=map) https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc Patterns of Morbidity (and Health) The incidence and prevalence of disease varies regionally, and morbidity rates can be used to show the severity of a disease in a particular country. Morbidity rates may also be used as a reflection of the general health of the population; countries with a higher prevalence of disease may be seen as less ‘healthy’, as overall the proportion of people in the population who are unwell is higher. Morbidity rates are shown through the incidence of diseases. In general, non-communicable diseases are higher in HICs, whereas infectious diseases or biologically transmitted diseases are more prevalent in LICs. This trend can be seen in the maps below; note how infectious diseases are higher in poorer regions such as Africa. HIV prevalence Diarrhoeal Diseases prevalence (Source:https://upload.wikimedia.org/wikipedia/commons/ (Source:http:/upload.wikimedia.org/wikipedia/commons/ d/d7/]HIV_Epidem.png) 5/51/Diarrhoeal_diseases_world_map) As previously mentioned, some diseases are more prevalent in high income countries. These diseases are usually influenced by lifestyle choices, e.g. lung cancer can be caused by smoking or poor air quality. Cardiovascular Disease Prevalence Lung Cancer Prevalence (Source:commons.wikimedia.org/w/index.php? (Source:www.theglobeandmail.com/life/health-and-fitness curid=50287978) /health/five-maps-that-put-cancers-global-spread-into-focus/) A mortality rate of a disease is dependent on the ability to treat morbidity. In general mortality rates are lower than morbidity rates as people can usually be treated. However, the proportion of those who die from the disease they have contracted is higher in LICs than HICs. https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc Fertility In general, fertility rates are lower in HICs than LICs. This is due to a number of reasons, for example: Less need for a larger family Access to contraception Emancipation of women The societal reasons behind why fertility rates decrease are explained in Stage 3 of the Demographic Transition Model, which will be explored later. Total fertility, estimates, 2010-2015 Population Structure All populations have a set structure with demographic variables: Age Gender The economically active: These are people, usually aged between the ages of 15-65, that contribute to the economy through labour. The dependants: Dependants are generally not working, meaning they do not contribute to the economy. Dependants are split up into young dependants (under 15) and elderly dependants (over 65). These are groups of people who are dependent on the contributions of the economically active to provide for their economy/them. Dependency Ratio The dependency ratio is the proportion of those economically active to those who are dependants. A high dependency ratio indicates there are a high proportion of dependants in the population compared to the economically active. High dependency ratios usually indicate that there is more pressure on the working population, as there are more people to provide for, and less people providing. https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc Issues associated with dependent populations Elderly populations Elderly populations have a high proportion of elderly people in comparison to the economically active and youthful dependants. This causes a population pyramid with a wide top and a thinner base. Elderly populations can cause several issues: More welfare spending (i.e. pensions and other benefits). In 2014/2015, 55% of welfare spending was spent on pensioners, and this is set to rise as the elderly population does. More pressure and spending in the NHS, as older people usually require more healthcare. This impacts those who use the NHS, as there is less time and resources available. Higher demand for healthcare/ social care professionals to support the elderly population, leading to pressure on these services when there is not enough labour available. A lower proportion of people in work, leading to lower tax revenues. Youthful populations Youthful populations have a high proportion of young dependants This causes a population pyramid with a wide base and a thin top. Youthful populations can cause several issues: Government expenditures into education, childcare, healthcare etc. with less people in proportion putting money into the government through taxes etc. Larger workforce required to support the needs of youths, which puts pressure on these services (e.g. larger class sizes in school because there are too few teachers) If fertility rates do not replace the population, then eventually there will be a larger elderly population, bringing the issues associated with it. Age-Sex Composition Age and sex are the two major demographic variables in a population, and these variables can indicate a country’s level of development. Age-sex composition can be shown on graphs known as population pyramids. Below are 2 contrasting population pyramids: https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc (Source: CIA World Factbook. Left (blue) is male population and right (red) is female population. Data is from 2016.) There are several things to note: LICs usually have population pyramids with wide bases, reflecting the high fertility rates.There is usually a large decrease in the population between the 0-4 age group and the 5-9 age group, indicating a high infant mortality rate. HICs usually have a higher proportion of elderly dependants than LICs, due to better healthcare and quality of life reducing morbidity. Compare the proportion of elderly dependants in Niger to Australia. In many LICs, there is a very high dependency ratio due to the high fertility rates (seen in Niger). In MICs and some HICs, there may be a large proportion of economically active people, shown in Australia by the bulge between 15-65. This is known as a demographic dividend. In HICs, there may be an ageing population, causing a high proportion of elderly dependants. In many HICs, this could be a possible issue in the future if the number of economically active is not in proportion to the number of elderly dependants. This population pyramid of Germany shows an ageing population, which is characterised by a large bump at the top of the pyramid. Demographic Transition The trends of natural population change (from the start of a population to present day) is represented within the Demographic Transition Model (DTM). This model shows how the birth rate and death rate change over time, and how this affects population numbers. In general, birth rates and death rates have both decreased. The model is separated into 5 stages, which are reflective of a country’s level of development. Usually, lower stages of the DTM usually indicate the country is less developed. https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc  Stage 1 High, fluctuating birth and death rates due to high levels of disease, pestilence, famine etc. Birth control is virtually non-existent, giving reason as to why birth rates are high, although they fluctuate in correspondence to pestilence/disease/famine etc. Population remains constant and low, as birth rates do not exceed the equally high death rates. Population is dependent on food, meaning any limits to food supply (e.g. from droughts or other disasters) would have significant effects on population. It is generally agreed that there are very few populations that are still in stage 1 of the model, aside from perhaps tribal communities. Stage 2 This stage is characterised by a fall in death rates. The reason behind the fall in death rates is due to major societal developments, for example the Agricultural Revolution. Advancements in healthcare, hygiene, and general living standards lower the incidence of disease, causing less deaths in that respect. Furthermore, increased food security also leads to less famines etc. lowering the death rate. Birth rates are still high (although it is important to note they are not increasing generally, they just remain high) leading to a rapid increase in population as there are more people living. A notable example of a country in this stage would be Angola, although many Sub-Saharan African countries, as well as Yemen, Afghanistan, and Iraq, fall into this category. Stage 3 In stage 3, birth rates start to fall due to further societal developments (lower fertility rates) These changes in society are less concerned with health and food like in stage 2; they are instead cultural and social changes. For example: The emancipation of women: Women’s rights become more recognised societally in this stage; it becomes more socially acceptable for women to choose whether they wish to have children, and how many they choose to have. Women are no longer seen as child bearers, but instead are beginning to work and earn their own living, decreasing birth rates. Contraception: Developments in science and the right for women to choose both lead to the development of contraceptive methods for birth control. The availability of contraception allows birth rates to fall. Reduced need for large families: As society develops, the need for a large family is reduced. In the past, children were assets to a family for labour, e.g. providing work on farms. As society develops, there is a shift in industry causing there to be less need for large families, e.g. living in an urbanised area. Furthermore, as death rates have previously fallen, it is now recognised that there isn’t a need for many children (i.e. there is less risk of them dying and the parents being left without carers). Education and change in societal values: Higher literacy rates (especially in women), education about contraception, and a more educated workforce all lower the need for many children. Furthermore, society’s view of the ‘ideal family’ changes, and it is no longer an expectation to have a large family, causing birth rates to fall. Many Low-Middle income countries are in this stage, including Mexico and India (both rapidly developing economies). https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc  Stage 4 Birth rates and death rates are both low, causing population growth to slow, but still grow overall. The majority of high income, developed countries are in this stage, including the UK. Stage 5 This stage is not officially in the model, but has been proposed. In this model, birth rates fall below death rates, causing a decline in population. Germany is usually named as an example of a stage 5 country, however unnatural population growth (migration) is changing the population structure. Age-sex composition graphs (population pyramids) can be related to the different stages of the DTM. (Source: CIA World Factbook. Left (blue) is male population and right is female population) STAGE 1 STAGE 2 STAGE 3 STAGE 4 STAGE 5? How Development Affects Life Expectancy and Infant Mortality Over time, it can clearly be seen that life expectancy has increased. This is due to developments globally, including healthcare, education, and better hygiene. https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc Development affects life expectancy in many ways: In general, life expectancy is higher in high income countries that are more developed. This is demonstrated by Western/Northern Europe, Australia, Canada, and Japan having the highest life expectancies (80-85). This trend of HICs having a higher life expectancy has been the case over time, these countries (aside from Japan) had higher life expectancies in the 40s/50s in comparison to the rest of the world. In contrast, the lowest income countries have the lowest life expectancies. This is most likely due to the poorer healthcare, water quality, sanitation etc. causing higher morbidity (illness). Sub-Saharan African countries have the lowest life expectancies, although this life expectancy has increased significantly since 1945, where many countries in Africa had life expectancies that were under 40. The rate of change of life expectancies is reflective of the rate of development. HICs were at a more stable state of development before LICs, meaning the rate at which the life expectancy has increased is slower. In Africa, contrastingly, the life expectancy has grown rapidly, but is still low. https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc Infant mortality is higher in less developed countries because there are less means of keeping a baby healthy and preventing illness when countries have less money/ services available. E.g.: Little/no access to specialist care for babies, meaning birth complications or issues with newborns cannot be rectified as easily and safely. This causes morbidity in many children, which can lead to infant mortality. Poor sanitation and poor access to clean drinking water, causing infections, illness, and dehydration. All of these are very dangerous to a newborn, and often fatal. Food insecurity, causing malnutrition and illness, often leading to death. The graph below shows infant mortality rates over time. In general, it can be seen that infant mortality rates are higher in less developed countries, but there is also the most rapid decrease of infant mortality in these countries. (Source: http://www.worldbank.org/: Mortality rate, infant (per 1,000 live births) ) Population-resource relationships Food Security Food security is the concept of having available, accessible, and affordable food that is safe and nutritious, so that people may live a healthy lifestyle. Food insecurity Not every population in the world has food security, in fact 1 in 10 people globally experience chronic hunger as they do not have access to sufficient food. Food shortages occur globally for a number of reasons, shown on the next page: https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc  Crops and livestock need to be in certain climates to thrive. They need the right amount of water, sunlight, and heat in order to survive. In extreme climates, there may be food shortages because food cannot grow there. Climatic hazards such as floods, droughts, tropical storms, and wildfires can be detrimental to crops and livestock. Annual crop yields can be severely affected by these events, causing food shortages. Lower Income Countries may lack the funding for agricultural technology and innovation (e.g. high yielding varieties of crops, equipment such as combine harvesters, equipment to dry/store crops etc). This causes less productivity and thus food shortages. In areas where agricultural productivity is poor, there is still opportunity to purchase food from other areas where productivity is higher. However, in poorer areas, many cannot afford to buy food, exemplifying the food shortages in LICs especially. Wars and severe political instability can majorly disrupt food supplies in a country. High death rates, displacement, and disruption to society can make it difficult to source food through growing it or importing it. Global links, e.g. trade agreements, can affect food supplies. Populations may be subject to food shortages if their country does not have a good deal with other countries. Effects of food shortages: Due to the lack of food available, and also the lack of variety of food when crops fail, widespread malnutrition and famines are common when there are food shortages. Deficiencies due to a lack in variety in food, causing diseases like rickets. People cannot afford to be picky when there is less food available, meaning many eat poor quality food to get by. Lower quality food can leave people vulnerable to a range of illnesses if the food is contaminated, such as diarrhoeal diseases or food poisoning. In areas where biologically transmitted diseases are common, malnutrition makes people less able to fight the disease, i.e. it is harder for the body to respond to - for example - malaria or diarrhoeal diseases when it is already malnourished. When agricultural yields fail, food prices can increase dramatically (as supply significantly decreases). For example, in 2016 maize prices in Malawi were 192% higher than the five-year average (many crops failed due to the extreme climatic event El Niño). When food prices rise, people can no longer afford a variety of food, meaning nutritional standards decrease, causing ill health. https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc Strategies to Ensure Food Security There are strategies to overcome food insecurity; not only can more food be produced, but the food that is available can be made more accessible, and waste can be reduced to save food. Increasing access Increasing amount Increasing efficiency Increasing a country’s Strategies and new Similar to increasing the access to foreign markets technology (e.g. GM crops) amount of food, increasing means they can import food, can increase the amount of the efficiency of a farm can increasing food security. food being produced, which save time and food, meaning therefore increases food overall there is more food Trading agreements such security as there is more available and it may be as trade blocs can be very food available, and this food more affordable as there beneficial to a country that is may also be healthier. are less expenditures. struggling to provide enough food for its Managing farms more Equipment and better population. successfully through management can produce training, farming equipment, more crops in less time, In times where food security and high yielding varieties helping affordability and is dangerously limited, such (HYVs) can increase food availability of food. as after a crisis or natural supplies. This means a disaster, aid and relief can country has more food Waste can be reduced by also increase food security. available to distribute to its harvesting natural resources population. and having better storage. Food production has increased in different regions for different reasons. For example, wheat and rice production has increased in Asia and Northern Africa due to higher yields, whereas maize production in Latin America and the Caribbean has increased due to methods of land expansion (creating more arable land). https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc In general, food production is unevenly distributed, with lower income countries producing the least amount of crops. The richest countries have the largest food supplies, meaning they produce enough/more calories for their population. This production trend varies crop by crop, usually due to environmental limitations in other countries, meaning consequent lower crops. Global Food Production per Region Current Regional Crop Yields (Source: http://storymaps.esri.com/stories/feedingtheworld/) https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc Examples of Regions with Differing Crop Yields Eastern Asia These areas have consistent high yields, due to the North America availability of resources, such as nutrients and water. Western Europe Eastern Asia receives high amounts of rainfall, facilitating in crop growth. The Great Plains in Central North America also create high yields. India These areas have moderate yields, but can be at risk of South America environmental limitations, such as droughts and flooding, Western Africa especially due to climate change. Central Australia Due to extreme environmental limitations, such as Saharan Africa droughts and temperatures unsuitable for crop growth, these Eastern Russia regions of the world have little if no crop growth to feed the population. For regional crop yields information, visit the FAO’s factfile: (www.fao.org/docrep/018/i3107e/i3107e03.pdf) Population Ecology Population ecology is the study of how the environment affects population factors, such as size, distribution, density, age-sex composition etc. Carrying Capacity The carrying capacity is the maximum population that can be supported in an environment without the environment being severely degraded. If the carrying capacity is reached it can have effects on the population as resources are no longer available to support the population. This is thought to lead to an increase in death rates and fall in birth rates until population numbers can be supported again (e.g. famines due to lack of food, causing deaths and lower fertility rates). Optimum population, underpopulation, and overpopulation An environment that supports a population can be of optimum population, or it could be underpopulated or overpopulated. Overpopulation Optimum population Underpopulation Too many people to be The ideal number of Too little people to fully supported by the people for the environment utilise the environment and environment and its and its resources. its resources. resources. Populations rely on their environment and its resources in order to be supported. Overpopulation and underpopulation are not necessarily concerned with how many people there are, but rather how many resources there are in order to support the people. https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc Take these 3 populations for example. = 1 person = the amount of food and resources needed for 1 person. Community 1 Community 2 Community 3 If an area had this amount of resources:...then community 2 would be the optimum population, community 1 would be overpopulated (as there are too many people compared to the resources available), and community 3 would be underpopulated (as there are too few people to utilise the resources). But if an area had this amount of resources:...then community 3 has an optimum population, whereas community 1 and community 2 are both overpopulated. It is important to consider that just because an area is densely populated, it does not mean that it is overpopulated if there are enough resources to support the population. This is the same for sparsely populated areas not necessarily being underpopulated. https://bit.ly/pmt-cc https://bit.ly/pmt-edu https://bit.ly/pmt-cc