Module 2 Human Population Growth PDF

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This material has been reproduced and communicated to you by or on behalf of University of the Philippines pursuant to PART IV: The Law on Copyright of Republic Act (RA) 8293 of the “Intellectual Property Code of the Philippines”. The University does not authorize you to reproduce or communicate this material. The Material may contain works that are subject to copyright protection under RA 8293. Any reproduction and/or communication of the material by you may be subject to copyright infringement and the copyright owners have the right to take legal action against such infringement. Do not remove this notice. © Institute of Environmental Science & Meteorology, College of Science, University of the Philippines Diliman 1 Module 2 Env Sci 1 (Environment & Society) Human Population & the Environment Image credit: Google Earth Pro https://givingcompass.org/article/world-population-day-family-planning/  Learning Outcomes ! Explain population dynamics & the factors that control population growth ! Discuss the human carrying capacity ! Examine how rapid human population growth is the fundamental environmental issue ! Describe Philippines population growth & its environmental impact Image from https://www.haaretz.com/us-news/.premium.MAGAZINE-how-many- people-have-have-lived-on-earth-1.6550893 3 © C.L.Ringor Human Population underlying nearly all environmental problems is the rapidly increasing human population Botkin & Keller (2011) https://ecowarriorprincess.net/2019/02/philippines-major- 4 problem-plastic-pollution-heres-what-theyre-doing-about-it/  The Prophecy of Malthus In 1798, Reverend Thomas Robert Malthus stated the human population problem in his writings “An Essay on the Principle of Population”. Malthus based his argument on three simple premises: (1) Food is necessary for people to survive (2) Passion between the sexes is necessary & will remain in its present state — so children will continue to be born (3) Power of population growth is infinitely greater than the power of earth to produce subsistence He argued that we are condemned by the tendency of population to grow geometrically while food production would increase only arithmetically. Unless birth rates were checked or wars & disease raised the death rate, the world would face inevitable famine & a subsistence standard of living. Critics of Malthus continue to point out that his predictions have yet to come true, technology has provided a way out, allowing us to live at greater densities. Supporters of Malthus respond by reminding them of the limits of a finite world. Who is correct? Image credit: https://en.wikipedia.org/wiki/Thomas_Robert_Malthus 5 World Population 2.1% in 1968 Growth, 1700-2100 The exponential increase of global population (13-fold over the course of four centuries), has amplified humanity’s impact on the natural environment. The greatest challenge our generation is facing is how to provide space, food, & resources for a large population in a way that is sustainable into the distant future. We should not make the mistake of underestimating the task ahead of us. Although new generations contribute, for now it is upon us to provide for them. Population growth is still fast even if the annual growth rate is decreasing: it is Population projected that in the next 31 years, we will add 64.5 million people in the world population every year. Even with a growth rate of 0.01%, 1.08 % in 2019 we will still reach 10.9 B in 2100. Where do we go from here? a te Growth R 0.04% was the average population growth rate between 10,000 BCE & 1700 0.01% Data sources: Our World in Data based on HYDE, UN, and UN Population Division (2019 Revision). This is a visualization from OurWorldinData.org, where you find data and research on how the world is changing. Licensed under CC-BY by the author Max Roser 6  Population group of individual of the same species living in the same area or interbreeding & sharing genetic information Image credit: https://www.dreamstime.com/world-population-globe-populated-stylized- human-figures-asia-d-rendering-world-population-globe-people-asia-china- image140802572 7 Basic Concepts of HIGH FERTILITY Population Dynamics Population dynamics is a general study of how population changes. Demographic transition is a model that describes population change over time Demography is the statistical study of human populations, & people who study the human population include demographers Five key properties of any population are (1) MEDIUM FERTILITY abundance, which is the size of a population; (2) birth rates, (3) death rates, (3) growth rates, & (5) age structure. How rapidly a population’s abundance changes over time depends on its growth rate, which is the difference between the birth rate & the death rate Population size increases through births & immigration; decreases through deaths & emigration Key factor that determines the size of a human population is the average number of children born to the women in that population (total fertility rate) LOW FERTILITY Human population can grow, decline, or remain fairly stable Botkin & Keller (2011); Miller & Spoolman (2016) 8 https://www.unfpa.org/SWOP-2018 Forecasting 1 Population Change We can write a formula to represent population change in terms of actual numbers in a population (Equation 1). However, sometimes it is difficult to get data of the different parameters required in the equation. We may use the exponential equation to forecast population change (Equation 2). We can apply this equation since we know that the population grows by a constant percentage per year. 2 We can also estimate the doubling time, which is the time it takes for a population to double its present size, using the equation T = 70/r where T is the doubling time & r is the annual growth rate expressed as a percentage. For example, the current annual growth rate of our global population is about 1%. It will take 70 years before the present population will reach twice its size. Botkin & Keller (2011) 9 Population Age Structure A more comprehensive approach in forecasting human population would take into account the effects of the supply of food, water, & shelter; the prevalence of diseases; & other factors that can affect birth & death rates. These factors have different effects on different age groups, & so the next step is to find a way to express how a population is divided among ages. This is known as the population age structure, which is the proportion of the population of each age group. The age structure of a population affects current & future birth rates, death rates, General types of population age structure. Data from 2019 United Nations, DESA, Population Division. & growth rates & has an impact on the World Population Prospects 2019. Licensed under Creative Commons license CC BY 3.0 IGO.https:// environment. It also has implications for population.un.org/wpp/Graphs/ downloaded 30 Aug 2020. current & future social & economic conditions as different age groups have many young people & a high death rate elderly, e.g., USA. An inverted pyramid different functions & needs. at each age—& therefore a high birth occurs when a population has more rate, characteristic of a rapidly growing older than younger people, e.g., Japan. population & also of a population with a A bulge occurs if some event in the past Age structure has four general types: (1) relatively short average lifetime, e.g., caused a high birth rate or death rate for pyramid, (2) column, (3) inverted Philippines. A column shape occurs some age group but not others, e.g., pyramid (top-heavy), & (4) column where the birth rate & death rate are low Australia. with a bulge. The pyramid age & a high percentage of the population is structure occurs in a population that has Botkin & Keller (2011) 10  Demographic Transition It is a three-stage pattern of change in birth rates & death rates that has occurred during the process of industrial & economic development of Western nations, leading to a decline in population growth. Stage 1 is a decline in the death rate. In a non-industrial country, birth rates & death rates are high, & the growth rate is low. With industrialization, health & sanitation improve & the death rate Theoretical demographic transition, including 4th & 5th stages that might take place in the future. drops rapidly. The birth rate remains Advances in treating chronic health problems could bring about Stage 4, in which the birth rate would high, however, & the population enters remain the same while the death rate fell. Stage 5 would be achieved only when the birth rate declined even further to match the decline in the death rate (Botkin & Keller, 2011). Stage 2, a period with a high growth rate. As education & the standard of living increase & as family planning methods become more widely used, the Such families have few children & put all & even young children earn for the population reaches Stage 3. The birth their resources toward the education & family’s survival. Unless rate drops toward the death rate, & the well-being of those few. there is a change in attitude among growth rate declines, eventually to a low parents—unless they see more benefits or zero growth rate. However, the birth Historically, parents have preferred to from a few well-educated children than rate declines only if families believe there have large families. Without other from many poorer children—nations is a direct connection between future means of support, aging face a problem in making the transition economic well-being & funds spent on parents can depend on grown children from Stage 2 to Stage 3. the education & care of their young. for a kind of “social security,” Botkin & Keller (2011) 11 Demographic transition will take place only if parents come to believe that having a small family is to their Image credit: https://creazilla.com/nodes/7220-happy- family-clipart benefit. Scientific analysis can show the value of small families, but this knowledge must become part of cultural values to have an effect. Botkin & Keller (2011) 12 Factors Affecting Human Population Size Factors Affecting Birth & Fertility Rates " Importance of children as a part of the labor force especially in less-developed countries. Many children in such countries have to work for wages to help their families survive Cost of raising & educating children. Birth & # fertility rates tend to be lower in more-developed countries, where raising children is much more costly because they do not enter the labor force until they are in their late teens or twenties Availability of, or lack of, private & public $ pension systems. Pensions reduce a couple’s need to have several children to paid employment outside the home. In less- developed countries, a woman with no education typically has two more children than does a woman with a high school education. Miller & Spoolman (2016) 13 https://rappler.com/bulletin-board/artists-against-child-labor-independence-day Average age at marriage (or, more % precisely, the average age at which a woman has her first child). Women normally have fewer children when their average age at marriage is 25 or older Availability of, or lack of, reliable birth control methods. Contraceptives allow women to control the number & spacing of & their children. Birth & total fertility rates are also affected by the availability of legal abortions. According to WHO & the https://fortune.com/2019/11/08/companies-that-openly-support-abortion-access/ Guttmacher Institute, each year, more than 208 M women become pregnant & at least 40 M of them get abortions—about 20 M of them legal & the other 20 M illegal (& often unsafe) Religious beliefs, traditions, & cultural ' norms. In some countries, these factors favor large families, as many people strongly oppose abortion & some forms of birth control Miller & Spoolman (2016) 14 https://time.com/5634762/northern-ireland-abortion-law-impact/  Factors Affecting Death Rates More people in some less-developed countries are living longer & fewer infants are dying because of larger food supplies, improvements in food distribution, better nutrition, medical advances such as immunizations & antibiotics, improved sanitation, & safer water supplies. ( Life expectancy: the average number of years a person can expect to live. The population of many of the richest countries in the world have life expectancies of over 80 years. In 2019, the life expectancy in Spain, Switzerland, Italy, & Australia was over 83 years. In Japan, it was the highest with close to 85 years. In the countries with the worst health life expectancy is between 50 & 60 years. The population of the Central African Republic has the lowest life expectancy in 2019 with 53 years. In the Philippines, the life expectancy in 1938 was 40 years. By 2019, we saw an increase to 71 years. Research indicates that poverty, which reduces the average life span by 7–10 years, is the single most important factor affecting life expectancy. https://ourworldindata.org/life-expectancy, downloaded 30 Aug 2020 Miller & Spoolman (2016) 15 https://en.wikipedia.org/wiki/Igorot_people Infant mortality rate: the number of babies 6.61% ) out of every 1,000 born who die before their first birthday. It is viewed as one of the best measures of a society’s quality of life because it reflects a country’s general level of nutrition & health care. A high infant mortality rate usually indicates insufficient food, poor nutrition & a high incidence of infectious disease. In areas with low infant mortality rates, women tend to have fewer children because fewer of their children die at an early age. Globally, the annual infant deaths have declined from 8.7 M in 1990 to 4.0 M in 2018, most of them in less-developed countries (WHO). The majority die of preventable causes during their first year of life. Pneumonia is the most common cause of death, preterm births & neonatal disorders are second, & diarrheal diseases are third. 2.00% In the Philippines, the infant mortality rate (deaths per 100 live births) is 6.6% in 1960. In 2021, it decreased to 2.0%. https://ourworldindata.org/grapher/infant-mortality downloaded 31 Jan 2024 Miller & Spoolman (2016) 16  Migration Affects an Area’s Population Size * Migration: the movement of people into (immigration) & out (emigration) of specific geographic areas. Most people migrate to another area within their country or to another country to seek jobs & economic improvement. But many are also driven to migrate by religious persecution, ethnic conflicts, political oppression, or war. There are also environmental refugees—people who have to leave their homes & sometimes their countries because of water or food shortages, soil erosion, natural hazards, or some other form of environmental degradation or depletion Miller & Spoolman (2016) https://www.thetimes.co.uk/article/abuse-of-rohingya-muslims-in-burma-is- 17 ethnic-cleansing-rex-tillerson-says-2zck3ks7g Human Population’s Effects on the Earth The danger that the human population poses to the environment is the result of two factors: the number of people & the environmental impact of each person. People have affected the environment for a surprisingly long time. Botkin & Keller (2011) https://ecowarriorprincess.net/2019/02/philippines-major- 18 problem-plastic-pollution-heres-what-theyre-doing-about-it/  Case Study: Easter Island The story of Easter Island has been used as an example of how people may degrade the environment as they grow in number, until eventually their overuse of the environment results in the collapse of the society. This story has been challenged by recent work. However, the primary lesson is that limited resources can support only a limited human population. When Polynesian people first reached it about 800–1,500 years ago, they colonized a green island covered with rich soils & forest. It took more than 1000 years for the expanding population to deplete its resources. Loss of the forest was irreversible: because it led to loss of soil, new trees could not grow to replace the forests. As resources grew scarcer, wars between the villages became common, as did slavery, & perhaps even cannibalism. Like Easter Island, our planet Earth is isolated in the universe & has limited resources. Its collapse is a metaphor, a worst-case scenario, for what may lie ahead of us in our own future. Of course, there are differences in our situation today that are in our favor. https://www.discovermagazine.com/planet-earth/easters-end Botkin & Keller (2011) 19 Image credit: Robert Harding, National Geographic Case Study: Mayan Civilization The ancient Maya, whose early settlements date back to about 2,000 BC, lived in present-day southern Mexico & northern Central America. As a civilization, they are recognized for their sophisticated calendar systems & hieroglyphic writing as well as their achievements in areas such as agriculture & architecture. Around 250 AD, the Maya entered an era in which they built flourishing cities with temples & palaces, & population size peaked. However, by around 900 AD, almost all of the major cities in what was then the heart of Maya civilization—the southern lowlands region, in present-day northern Guatemala & neighboring portions of Mexico, Belize & Honduras—had been abandoned. The collapse did not happen all at once; instead, it is believed to have occurred over time from place to place. Scholars have suggested a number of potential reasons for the downfall of Maya civilization in the southern lowlands, including overpopulation, environmental degradation, warfare, shifting trade routes & extended drought. However, the Mayans did not disappear in the aftermath of the collapse. They built cities in the northern lowlands region & in the highlands region where they cleared more ancient rain forests for farm lands. https://www.history.com/news/why-did-the-maya-abandon-their-cities Image20 credit: Charles & Josette Lenars, National Geographic  Total Impact of Human Population on the Environment This three-factor model is a good starting point in understanding the total impact of human population on the environment. The environmental impact of population on a given area depends on three factors: population size (P)— the number of people—, consumption per person (A), & technological impact per unit of consumption (T). The impact per person varies widely, A simple three-factor model of environmental impact of population in developing & developed within the same nation & also among countries. Image credit: Miller (2003). nations. The average impact of a person who lives in a developed so powerful that our effects on the standard of living & slowing overall country is much greater than the environment are even more global & human population growth. Improving impact of a person who lives in a significant. This could cause a the standard of living increases the developing country. But even in a poor, negative feedback—the more people, total environmental impact, countering nation, the sheer number of people the worse the environment; the worse the environmental benefits of a decline leads to large-scale environmental the environment, the fewer people. in population growth. effects. This simple three-factor model reveals The problem now is that there are so a great irony involving two many people & our technologies are humanitarian goals: improving the Botkin & Keller (2011) 21 Pandemics & World Population Growth Although outbreaks of the well-known traditional epidemic diseases have declined greatly during the past century in industrialized nations, there is now concern that the incidence of pandemics may increase due to several factors. One is that as the human population grows, people live in new habitats, where previously unknown diseases occur. Another is that strains of disease organisms have developed resistance to antibiotics & other modern methods of control. A broader view of why diseases are likely to increase comes from an ecological & evolutionary perspective. The 7.7 B people on Earth constitute a great resource & opportunity for other species; it is naive to think that other species will not take advantage of this huge & easily accessible host. From this perspective, the future promises more diseases rather than fewer. This is a new perspective. Image credit: https://www.statnews.com/2020/02/11/disease-caused-by-the- Botkin & Keller (2011) novel-coronavirus-has-name-covid-19/ https://www.fda.gov/food/food-safety-during-emergencies/food-safety-and-coronavirus- 22 disease-2019-covid-19  Tragedy of the Commons The population problem has no technical solution; it requires a fundamental extension in morality. -Garrett Hardin Tragedy of the commons is the depletion or degradation of a potentially renewable resource to which a large number of people have free & unmanaged access. For example, the depletion of commercially desirable fish species in the open ocean beyond areas controlled by coastal countries; air & ocean pollution; global warming. When a resource is shared, an individual’s personal share of profit from its exploitation is usually greater than his or her share of the resulting loss (i.e., resource depletion or environmental degradation). Individuals always act for his own benefit. In the short run, everyone seems to gain, but in the long run, everyone loses. Complete freedom of action in a commons inevitably brings ruin to all. The implication seems clear: without some management or control, all natural resources treated like a commons will inevitably be destroyed. Hardin (1968) Image credit: Jilson Tiu Greenpeace https://www.greenpeace.org/philippines/press/1131/garbage-engulfing-manila-philippines- 23 after-severe-storm-highlights-plastic-and-climate-crises/ © CLRingor The Human Carrying Capacity of the Earth Carrying capacity is the number of individuals of a given species that can be sustained indefinitely in a given space (area or volume). In humans, it is simply the number of people who can live on earth at the same time. What is the human carrying capacity of the earth? The answer depends on The “sigmoid growth form” curve & the carrying capacity. This curve describes the increase in human what quality of life people desire & are population with finite resources. When a population reaches the upper limits of carrying capacity, it may willing to accept. Think about your remain at this or decline (Pulselli & Coscieme, 2014; Odum, 1971) own needs at different stages of your life. Think about how much resources Estimates vary significantly: from 2.5 - effect of increasing the Earth’s are required to sustain those needs & 40 B, with about 15 B as the upper carrying capacity for our species. The think about where these resources are limit with today’s technology. average life expectancy in most of the coming from. Then multiply that by world has been steadily rising, despite 7.7 B, the current human population. Are there physical limits to human warnings that we are seriously population growth on a finite planet? degrading Earth’s life-support system. Calculation of the human carrying Some say “yes”. Others say “no”. They believe that we can avoid capacity of the Earth is complex due serious damage to our life-support to the great variety of resources that Those who say “no” argue that systems by making technological humans take from the environment, technological advances have allowed advances in areas such as food the great quantity of wastes they put us to overcome the environmental production & medicine, & by finding back & the range of their possible limits that all populations of other substitutes for resources that we are technologies, institutions & lifestyles. species face & that this has had the depleting. Miller & Spoolman (2016) 24  scientific underpinnings of the PB framework scientific understanding of ES functioning with sphere integrity—are recognized as “core” PBs science.sciencemag.org/ on August 31, 2020 are updated and strengthened. the precautionary principle, the PB framework based on their fundamental importance for the identifies levels of anthropogenic perturbations ES. The climate system is a manifestation of the RATIONALE: The relatively stable, 11,700-year- below which the risk of destabilization of the amount, distribution, and net balance of energy long Holocene epoch is the only state of the ES ES is likely to remain low—a “safe operating at Earth’s surface; the biosphere regulates ma- terial and energy flows in the ES and increases its resilience to abrupt and gradual change. cooking; soil erosion, decline in Anthropogenic perturbation levels of four of the ESgroundwater supplies, processes/features (climateclimate change change, bio- sphere&integrity, many others. biogeochemical flows, and land- system change) exceed the proposed PB (see the At some point, we could reach one or figure). more planetary CONCLUSIONS: PBs areboundaries. scientifically based levelsExceeding such boundaries of human perturbation could of the ES beyond whichlead to damaging ES functioning maylong-term changes be substantially altered. Transgression & the possibility of of theaPBs thusdecline sharp creates in substantial risk of destabilizing the Holocene the human population due to state of the ES in which modern societies have increasing evolved. death rates. The PB framework does not dictate how societies should develop. These are po- liticalIndecisions addition tomust that degrading include our life- considera- tion ofsupport the human system, we including dimensions, failed toequity, provide not incorporated in the PB framework. equitable & just access to resources. Never- theless, by identifying a safe operating space UN reported for humanity that the on Earth, in 2015, more than PB framework 736 aMvaluable can make peoplecontribution lived below the to decision- makers international povertycourses in charting desirable line (USD 1.90/ for socie- The planetary boundary framework provides a science-based analysis of the risk that human Current status of the control variables for seven of the planetary boundaries. The green zone perturbations will destabilize the Earth’s system at the planetary scale. Nine planetary boundaries have ▪ day) & around 10% of the world tal development. population is living in extreme poverty is the safe operating space, the yellow represents the zone of uncertainty (increasing risk), and the been identified. Of these, biosphere integrity (genetic diversity) & biochemical flows (P, N) are already at highred risk.isImage a high-risk zone. credit: The et Steffen planetary al. 2015boundary itself lies at the intersection of the green and yellow & struggling to fulfill the most basic zones. The control variables have been normalized for the zone of uncertainty; the center of the needs. How will we meet & sustain figure therefore does not represent values of 0 for the control variables. The control variable shown Those who say for climate “yes” change argue thatCO2 concentration. is atmospheric caused by for Processes drought or by a shortage which global-level boundaries The list the basic of author needs affiliations of inthe is available additional the full article online. 2 B sooner or later, we will reach the limits of energy for transporting cannot yet be quantified are represented by gray wedges; these are atmospheric aerosol food;loading, people *Corresponding projected author. in 2050? E-mail: [email protected] Cite this article as W. Steffen et al., Science 347, 1259855 thatnovel nature eventually entities, imposesrole and the functional on of any desertification; dispersal of certain biosphere integrity. (2015). DOI: 10.1126/science.1259855 population that exceeds or degrades pollutants, such as toxic metals, into No one knows how close we are to its resource base. On 736 13 FEBRUARY 2015our finite VOL planet, 347 ISSUE 6223 waters & fisheries; disruption in the environmentalsciencemag.org limits that some SCIENCE the human population will eventually supply of nonrenewable resources, analysts say eventually will reduce the be limited by some factor or such as rare metals used in making size of the human population primarily combination of factors. Some of steel alloys for transportation by sharply increasing the human these are disruption of food machinery; decrease in the supply of death rate. We must confront this vital distribution in a country, commonly firewood or other fuels for heating & scientific, political, economic, & ethical issue. Miller & Spoolman (2016) 25 Philippine Population the population of MM increased by 5.2 M (7.5 M in 1988 & 12.7 M in 2014). As population grows, we have to build infrastructures needed to live such as housing, transportation, The Growth of Metro Manila (MM) work places, schools, places of worship, hospitals, shopping malls, business centers, recreational areas, market places, Satellite (Landsat) images taken in 1988 & 2014 clearly show telecommunications, etc. We have already encroached the La the expansion of built-up areas in MM & its neighboring Mesa Watershed protected area, the main source of drinking provinces of Cavite, Bulacan, & Laguna (built-up is shown in water in MM. gray; farmland & forest are light green). During the same period, Population data retrieved on 31 Aug 2020 from https:// www.macrotrends.net/cities/22109/manila/population 31 Jan 1988 7 Feb 2014 La Mesa Watershed © Jilson Tiu Greenpeace https://www.greenpeace.org/philippines/press/1131/garbage-engulfing-manila-philippines- 26 https://landsat.visibleearth.nasa.gov/view.php?id=86780 after-severe-storm-highlights-plastic-and-climate-crises/ © CLRingor How did the Philippine population change over time? Total population Average annual rate of population change The Philippine population saw a rapid increase between 1950-2000, with a The average annual growth rate declined from 3.5% (1950) to 1.4% ( 2019). doubling time of 25 years. Since then, the population growth slowed & is Compared with SE Asia & combined E & SE Asia regions, this rate is higher. projected to double in 75 years (under the medium variant). As of August It is projected to continue to be higher until 2100. 2015, the Philippine census reported a population of 100.98 M. Population age structures show demographic transition from Stage 1 in 1950 to Stage 2 in 1990. Presently we are transitioning to Stage 3 & is forecasted to fully transition by 2050. Image credits: UN World Population Prospects 2019 27 Average annual number Number of births/deaths (M) Total Fertility of births & deaths Live births per woman Between 1950-2000, the average annual number of births rose from 1 M to As discussed, the key factor that determines the size of a human population 2.4 M. Since then, it has declined to 2.2 M in 2019 & is projected to is the total fertility. It is declining since 1950 when live births per woman was decrease until 2100. The average annual number of deaths, however, is 7.5. In 2019, it was about 2.5. The total fertility is higher than SE Asia & E & increasing since 1950. After 2080, this number will exceed births & our total SE Asia since 1950. It will be equal to these regions by 2060. population will drop. Life expectancy at birth Mortality under age 5 Deaths under age 5 years Life expectancy at birth (males & females) per 1000 live births (years) Filipinos have been living longer since 1950 when people have life Deaths under age 5 years per 1,000 live births has been declining since expectancy at birth of about 56 years. Currently, our life expectancy is 71 1950. We saw a sharp decrease from 140 deaths in 1950 to 40 in 2000. At years & is projected to be 82 years by 2100. Compared to our neighboring present, it is about 25. Comparing with other SE Asian countries, we have countries, our life expectancy is higher compared from 1950-1975. But by much fewer deaths from 1950-1975. However, starting in 2012, it has 2008, it has become lower. This trend is projected to continue until 2100. become slightly higher than our neighboring countries. UN World Population Prospects 2019 28 Key Factors Affecting Philippine Population Total Fertility Under the medium variant projection, our population will continue to increase until 2075. What are some of the key factors that contribute to this growth? ♀ Total fertility (TF). 2014 data shows that the TF in the Philippines is 3, which is higher than Indonesia, Vietnam, Malaysia, & Thailand (Worldbank). Those living in rural areas has higher, 3.5, TF than those who are in cities, 2.6. + Unplanned pregnancies. 2013 survey shows that the preferred family size of urban women is Regional comparison of total fertility. Data from Worldbank, 2014. only 1.9 but the TF is 2.6; for rural women, it is only 2.5 but the TF is 3.5 (NDHS). , Unmet need for family planning. 2013 data Average childbearing age. 2013 data shows shows that 17.5% of Filipinas who do not wish that 10.1% of women aged 15-19 & 46.2% of & to become pregnant are not using contraceptives or practicing family planning; 44.9% percent of married women aged 15-49 women aged 20-24 have begun childbearing (NDHS). are currently not using contraceptives (NDHS). 29 Availability of, or lack of, opportunities for Life expectancy at birth & infant mortality. women. 2013 data shows that 43.5% of women aged 15-24 who have begun ( According to UN (2019), the life expectancy at birth of Filipinos is increasing & mortality under # childbearing have no education. In contrast, age 5 is decreasing. those have reached or finished college, have lower percentage of childbearing (20.5%). Additionally, most of these women belong to poor households (see graph on the right) Religious beliefs, traditions, & cultural norms. Based on the 2010 census of NSO, about 81% of Filipinos are Catholic. The Catholic Church opposes the RH Bill ' (Responsible Parenthood & Reproductive Health Act of 2012), which guarantees universal & free access to nearly all modern contraceptives for all citizens. Also, our culture dictates that we take care of our parents in their old age (aside from the fact that there is a lack of senior care services in the Philippines), hence the more children, the more caretakers. Percentage distribution of women aged 15-24 who have begun " childbearing in relation to their educational attainment & economic status. Importance of children as a part of the labor Data from NDHS, 2013. force or a source of financial support. Do you think this still applies to us? 30  ELEVATION MAP Environmental Limits to Population Elevation (meter above sea level, masl) Growth in the Philippines The physical environment & geographic location of the Philippines are some of the possible limiting factors to population growth. One of these is land surface. The Philippines is archipelagic with a total land area of 300,000 km2 (DENR), of which 41.7% (Worldbank) is allotted for agricultural activities. This means we have roughly 60% of land available for other uses, such as for residential, commercial, & industry. But not all land space is habitable within the limits of our present technology. The islands, which are volcanic in origin, are mostly mountainous (see Elevation Map). Most of these mountain ranges have elevations of more than 500 masl (meter above mean sea level). It takes a lot of effort to build communities in highlands. Of course, we may opt to build a conglomerate of cities like Baguio, which sits at about 1,400 masl. http://www.baguio.gov.ph/about-baguio-city http://data.worldbank.org/indicator/AG.LND.AGRI.ZS) 31 Image credit: Bureau of Soils & Water Management SLOPE MAP These mountains have also steep slopes (see Slope Map). Some areas, especially the Cordillera & the Sierra Madre mountains, have extensive land surface with slopes greater than 50%. Imagine building a house on that land, let alone establishing communities. We also have to consider conservation & protected areas. How much land area should we allocate to keep our forests intact? Not only because of the ecological services they provide, like regulating climate & preventing soil erosion, but because it is our moral responsibility. People do not only need a house to live. As population grows, all the other needs should also increase. As mentioned — transportation, work places, schools, places of worship, hospitals, shopping malls, business centers, recreational areas, market places, telecommunications, etc — all these need a space to be built. In addition, population growth will decrease the hectares of arable land for each person. For example, in case of rice, production is constrained by the fixed amount of available arable land but rice consumption must increase steadily to feed the growing population. 32 Image credit: Bureau of Soils & Water Management  Another limiting factor is our exposure to natural hazards (see Even if we can build tall residential buildings, the risk for map below) such as typhoons, heavy rains (because of collapse due to earthquake is high. We have not even monsoon), earthquakes, & volcanic eruption. Each of these considered sea level rise because of global warming. hazards cascades into another hazard like floods, landslides, Figure & erosion. Even if we1. can Location of citiesonbysteep build communities population sizeLocation and level of exposure to natural disaster of cities by population size & level of exposure to natural disaster. The mountain slopes, the risk for landslides & erosion is high. Philippines has high exposure to disaster. Metro Manila was highly exposed to typhoons, floods, earthquakes, landslide, & volcanic eruption & was exposed to low risk of droughts (Gu, 2019). Image credit: Gu (2019) 33 orld Urbanization Prospects: The 2018 Revision; Dilley et al. (2005) r: The designations employed and the presentation of material on this map do not imply the expression of any opinion whatsoever on the part of the Secretariat of t egal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. Dotted line represents approximately t Kashmir agreed upon by India and Pakistan. The final status of Jammu and Kashmir has not yet been agreed upon by the parties. Final boundary between the Republi th Sudan has not yet been determined. A dispute exists between the Governments of Argentina and the United Kingdom of Great Britain and Northern Ireland concernin ands (Malvinas). Sustaining the Philippine Population People as Resources UN projects we will reach 155 M by 2075 before our Humans can be assets & not as liabilities. They can help population will start to decline. In means adding 45 M to solve environmental issues (which humans caused in the our current population of about 110 M in a span of 50 first place). But we need resources for people to be years. Within that period, can we sustain this population resources. We need to invest not only for their food, growth? To answer this is to know the carrying capacity clothing, & shelter but more so for their education, of our country. training, & medical care. From the moment they were conceived until the day they die, we should provide for We have discussed that the detection & estimation of their needs for them to become human capital. Can we? carrying capacity is a very complex issue. It does not depend on fixed, static, or simple relations but on Sometimes, for a society to be sustainably developed, it variables such as rapidly changing technology, has nothing to do with the actual number of people, but preferences, structure of production, consumption, living the values & abilities of individuals. For example, Japan’s standards, degree of distributional equality, trade population (127.11 M in 2015) is larger than the extension, waste generation, resource availability, Philippines (100.98 M in 2015) but they have better policies, & so on. Add to this are the environmental environmental condition & economic development. limits to growth that are inherent in the Philippines & the 7 global biophysical limits (planetary boundaries). We also People should have the freedom to produce as many have to consider infectious disease outbreaks or children as they want, but only if it does not reduce the pandemics, such as what we are experiencing right now. quality of other people’s lives now & in the future, either by impairing the earth’s ability to sustain life or by Do you think that the Philippine population is causing social disruption (Hardin, 1968). Limiting the sustainable? freedom of individuals to do anything they want in an effort to protect the freedom of other individuals. 34 Summing Up Population dynamics is a general study of how population The acceptable carrying capacity is not simply a scientific changes. issue; it is an issue combining science & values. Demographic transition is a model that describes population The maximum population Earth can sustain & how large a change over time. population will ultimately be attained by human beings are controversial questions The human population growth rate is directly controlled by birth & fertility rates, death rates, & migration. Although the average annual rate of population change is declining from 1950-2019, the Philippine population saw a It is important to consider the age structure of a human rapid increase between 1950-2000. Since then, the population population since it affects current & future birth rates (e.g., growth slowed & is projected to stabilize in 2075 (under the childbearing age), death rates (e.g., prevalence of diseases), & medium variant). As of August 2015, the Philippine census has an impact on the environment. It also has implications for reported a population of 100.98 M. current & future social & economic conditions as different age groups have different functions & needs. Some key factors affecting the Philippine population growth are total fertility, unplanned pregnancies, unmet need for family The Tragedy of the commons imply that renewable resources planning, average childbearing age, opportunities for women, that are freely available can be degraded. religious beliefs, traditions, cultural norms, life expectancy at birth, infant mortality & children as potential financial support. The human population is often referred to as the underlying environmental issue because much current environmental Some of the environmental limits to population growth in the damage results from the very high number of people on Earth Philippines is the available land surface area & its attributes, as & their great power to change the environment in order to live & well as exposure & vulnerability to natural hazards. to satisfy their wants & needs. 35 Study Questions What controls the human Why is rapid human population population growth rate? growth a global environmental What is population dynamics? problem? Why is it important to consider the What is demographic transition? age structure of a human What does the tragedy of the population? commons imply? How did the Philippine population How could you determine the change over time? carrying capacity of the earth? What are some of the environmental limits to population What are some of the key factors How many people can earth growth in the Philippines? affecting the Philippine sustain? population? 36 Learning Activities Ecological Footprint To know if we are living sustainably, we have to know our ecological footprint. Ecological footprint is the amount of biologically productive land and water needed to supply a population with the renewable resources it uses and to absorb or dispose of the wastes from such resource use. It is a measure of the average environmental impact of populations in different countries and areas. Estimate your own ecological footprint by using this calculator https://www.footprintcalculator.org/. Is your ecological footprint larger or smaller than you thought it would be, according to this estimate? Why do you think this is so? Even if each individual will reduce his/her ecological footprint, unsustainable human population growth can overwhelm these efforts. We do not only need smaller footprints, but fewer feet as well. Do you agree? Why? Why not? This activity is not compulsory but please take time to do it. It is not only unexpectedly enlightening but fun as well. 37 Learning Activities Reflection Paper Write a reflection paper about this topic discussed in the class & in this module. Write what you used to think about or know, what you know now, and what you are not sure of or what you want to learn more. Be specific. This activity is not compulsory but please take time to do it. It is not only unexpectedly enlightening but fun as well. View at the back of IESM building, UP Diliman campus. Photo by CLRingor, 3 Aug 2021. © CLRingor 38 References Botkin, D. B. & Keller, E. A. (2011). Environmental Science Steffen, W., Richardson, K., Rockström, J., Cornell, S. E., Earth as a Living Planet, 8th Ed. USA: John Wiley & Sons, Inc. Fetzer, I., Bennett, E. M., Biggs, R., et al. (2015). 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