The dependency theory relates to the argument that core countries exploit periphery countries, i.e., third world nations, to enrich themselves, while the latter remain poorer and often, powerless. Proponents of this theory contented that resources originate from periphery or underdeveloped nations and end up in the core or developed countries, enriching the latter at the expense of the former (Norton & Mercier, 2016). As a result, periphery nations continue to depend on core nations. 3
- Population Density
Population density denotes the degree of population distribution or clusters in a particular area, country, region, or the world (Malpezzi, 2013). It is the total number of people living in a unit area. In some situation, the density can be even, while in others, it can be uneven. For instance, Canada’s population density is unevenly distributed; cities have high population density, while larger areas have low density. The 2014 single statistics produced a population density of 3.5 people per square km. despite a combination of large unpopulated and relatively small-populated areas (Norton & Mercier, 2016). Nonetheless, one can infer that population density refers to how number of people living in a particular place, or, in other words, how populated an area is. 3
- S-shaped Curve
An S-shaped curve occurs when the process of growth starts slowly, then increases rapidly or exponentially, and then levels up at the peak. In other words, before high population density in an area is achieved, the population starts growing at a low momentum but in a positive acceleration during the early phases, after which it reached a climax/top-speed growth rate that is rapid. After the rapid increase, the growth reduces in a negative acceleration to a level where the population achieves stability or equilibrium and stabilizes with no more growth. 3
- Malthusian Theory
The Malthusian theory is premised on the idea that humanity needs food for its continued existence. Similarly, sexual intercourse between opposite sexes is a necessity for the continuation of the species. However, the rate of population growth is higher than the rate of food production. Consequently, according to Malthus, population will rise to reach a point where it will surpass resource growth, such as food production or availability, putting stress on the means of subsistence. Nevertheless, in theory, if human rationality is something to go by, methods such as family planning and moral restraints such as deliberately delayed marriages and singlehood can be adopted, reducing fertility rates, which might end up correcting the population-food imbalance. On the contrary, people cannot voluntarily use such methods, and hence natural forces such as war, famine, flood, and disease continue to keep human population at a manageable level. The theory warned humanity of the likelihood of an impending catastrophe owing to unchecked population growth. For example, the world wars II and II started because nations could not solve their conflicts over resources. He did not anticipate the dramatic increase in food production. 2
A refugee is a foreign national forced to leave own country because of being affected by war, persecution by the state, or natural disaster. A person is considered a refugee when they unwillingly leave their home country to seek safe haven elsewhere because the situation in their home country makes life untenable. Therefore, such people go to stay in another country as they wait for normalcy to return to their country of origin. Syrians leaving their homes in Syria to seek safety in Europe and Turkey are refugees. 3
Population growth models play an important role in explaining various population dynamics affecting different species or organisms (Mateo, Arroyo, & Garcia, 2016). Similarly, they help in research to create a correlation with decrease or increase in population and its impact on the environment. Such models facilitate the understanding of complex processes and interactions in nature. In this regard, modeling in nature provides manageable mechanisms for scientists to understand changes in the population size in a given time period and to make sense of these changes. Therefore, population modeling is used a tool for identifying certain patterns related to population change (Hastings, 2013). For instance, it is possible to study the impact of population increase or decrease on the environment. Similarly, through modeling, patterns will emerge showing the effects that a change in the population of one species has on other species as well as intra-species implications. Hastings (2013) explains how modeling of human population improved the understanding of demography, which tells about a country’s population composition, resource use, population growth rate, population density and distribution, as well as age and life expectancy. Additionally, demographics are vital in policymaking, national planning and resource allocation. This vitality explains the value of population modeling. Creating an appropriate population model is expected to improve the understanding of the factors that drive population growth, and scientists gain knowledge concerning resource usage and consequence of population growth on the environment.
There are five primary models explaining population growth and its effects on natural resources. These models are the S-shaped Curve, Malthusian theory, Marxist theory, Boserup theory, and the Demographic transition. The S-shaped curve model explains that when an area’s population density starts increasing, it begins slowly in a positive acceleration manner, followed by rapid growth so that it reaches exponential growth rate before leveling up to a point of equilibrium, that is, zero growth rate (Tobin & Dusheck, 2005; Forman, 1997). The zero growth rate is also known as the carrying capacity. The negative acceleration comes into play because environmental resistance increases in times of high population density. For this model to be effective, it is produced under controlled experimental conditions. However, Norton and Mercier (2016) contend that even though population growth may begin slow and then acquire momentum, it is normal for plant and animal population to remain steady at the top. Sometimes, the final stage of growth can involve some oscillations. Even as the S-shaped curve can predict growth, it fails to take into account external factors such as economic and cultural factors. For instance, in view of fertility issues, the human decision to control birth rates willfully can affect population stability, while natural law cannot do so.
Mishra (1995) and Yamaguchi (2014) explain that according to Malthusian theory, human population growth happens at geometrical progression, and would therefore outstrip human capabilities of food production as this increases arithmetically. As a result, the land resource, which is the source of food, directly restricts population growth, density, and size. When population outruns subsistence resources such as food, the imbalance is corrected by preventive checks comprising moral restraints such as delayed marriage, family planning, and celibacy (Van Bavel, 2013). However, Norton and Mercier (2016) explain that since people are unable to use such methods, positive checks like famine, natural disasters such as floods and drought, war, and disease increase mortality rates, and work to reduce population. Consequently, human population is reduced to environmentally sustainable levels. The underlying assumption is that natural resources such as land are fixed, making it hard to increase food production. The theory’s shortfall lies in focusing on food production technologies alone, while ignoring the effects of technological changes and their effects on the environment. Moreover, Malthusian theory does not discuss the consequence of population change on the environment or food production technologies.
Esther Boserup’s theory criticizes Malthusianism and holds that increase in population pressure results in innovation and technological changes. As a result, land is put to better use, and production rates, quantity and quality increase. Land intensification ensured forest or fallow land is transformed into multiple cropping feed that help increase food reserves to feed the growing population (Mishra, 1995). However, the challenge of the Boserup model is that while food production increases at an overall level, it decreases at a per capita level. The decrease in production results from high population density, which in turn raises poverty levels, and leads to limited application of agricultural technologies. The Boserup model’s application is limited to underdeveloped society that practice subsistence farming and production (Norton & Mercier, 2016). Even though the model seems to suggest that populations can continue to grow, the Malthusian argument that the earth has a limited carrying capacity appeals to many.
Marxist theory, as postulated by Karl Marx, holds that population growth is directly related to the prevailing mode of production practiced in a society or country. From a Marxist perspective, capitalism is the primary source of poverty and not population growth, as suggested by Malthus. Marx argued that capitalism increased social inequality by promoting unjust distribution of resources, thereby increasing poverty (Norton & Mercier, 2016). Subsequently, he held that increasing poverty level only helps to increase surplus population made up of surplus-unemployed workers who are a reserve labor force. Existence of such labor force keep wages low and profits high for the owner/s of the means of production. Basically, increase in social inequality acted in favor of the few. The Marxist theory falls short of explaining how production systems perpetuate social inequalities; it does not discuss on the effects of population growth on resources.
The demographic transition model explains population shift from high to low mortality and issues of fertility because of social and economic changes and developments. It infers that since mortality rate go down before a reduction in fertility, the population of a given organism, that is, humans, tends to increase rapidly and reach exponential growth (Van Bavel, 2013). This demographic transition becomes complete when mortality and fertility rates stabilize at low levels (Mishra, 1995). Unlike other models of population growth, the demographic transition model is more realistic considering that it is based on facts as opposed to relying on general assumptions. The disadvantage of this model is that since it is generally descriptive, it does not give strong and emphatic hypothesis on population-resource relationship. However, this model is better suited to explain population growth because elements such as technology changes, resource availability, economic and social factors, and the environment affect population growth. Based on observation of western countries, so may not apply everywhere.
Figure 1: 2015 Population Pyramid of Canada P
Figure 2: 2015 Population Pyramid of Nunavut P
Figure 3: 2015 Population Pyramid of British Columbia P
- Canada and British Columbia have a beehive-shaped population structure due to a diminishing birthrate and an expanding middle-aged population. The two are comparable in terms of life expectancy and aging population. Nunavut, on the other hand, has a predominately youthful population and is seen to have a higher birthrate compared to British Columbia and Canada. P
- Over the next 20 years, it is likely that Nunavut’s high birthrate will decline, as the government will have put in place measures to curb population growth or bring down supply of labor. A large base today, which will be moving into their reproductive years, so this would take some time. Likewise, since a huge proportion of the British Columbia’s middle-aged population will be aging, authorities will strive to find ways to take corrective measures to increase the birthrate or encourage immigration to avert a situation of jobs remaining unfilled.
- In 10 years from now, there is like to be a shortage of workers in British Columbia. Without immigration – puts pressure on services etc.However, the opposite is true for Nunavut, which currently has a high birthrate. It will have more people of working age with a limited number of job opportunities. Or, plenty of people available to engage in the workforce and support the elderly and young.
After the industrial revolution, humans were able to enhance their living standards. The human factor as the main source of labor reduced in importance, and production increased. Progress into the 21st century led to the age of technology and scientific development, and then to the age of manufacturing. Even production methods continuously evolved, helping to improve the quality of production. Consequently, satisfaction levels went up. People now had enough to eat and live in healthy conditions, a fact that quickly led to population explosion (van Bavel, 2013). However, of greater concern are the long-term negative effects of industrialization on the environment. Issues like overexploitation of natural resources and environmental pollution emerged after the industrial revolution.
According to van Bavel (2013), industrial pollution and energy needs, which emanate from human activity, are the primary cause of environmental degradation, especially in developing countries. Its precipitator is the need for cheap energy to fuel economic growth. Consequently, developing countries opt to use fossil fuels as petroleum and coal that produce immersed smoke particles that are recipe for environmental pollutants. Industrial pollution can affect water, air, soil, wildlife, and even cause global warming. For instance, the hot water from thermal plants adversely affects aquatic life in rivers and oceans (Emmott, 2013). The 21st century is known for its vast use of machinery and technologies, which has led to increased demand and consumption of energy. Correspondingly, energy use and production is a major contributor to global warming and accounts for a substantial figure of human-induced gas emissions that hurt the environment.
Industries require large volumes of water for their operations. Resultantly, water is exposed to radioactive material and other harmful chemicals, water that finds its way back to the rivers, lakes, and oceans. The result is that manhumans or people, animals, and fish are exposed to harmful substances, resulting in death and extinction. Similarly, people are also exposed to health hazards because farmers use water for irrigation. Subsequently, the soil becomes polluted and the vegetation is destroyed. On a similar note, air pollution by industries leads to a gradual destruction of the atmosphere. Industrialization is a capitalist economic system, targeting maximization of profit and increase productivity. People use toxic fertilizers, pesticides, and irrigation practices that affect the environment, with the sole aim of making profit and not caring about the consequences. Worryingly, natural patterns have changes and some others collapse making it hard for some species of plants, microorganisms, and animals to become extinct. The idea is that as factories develop, they take up spaces occupied by other animals, leaving them without a habitat and struggling to survive.
The United Nations Department of Economic and Social Affairs, Population Division (UNDESA) (2015) revealed in 2010 that with a population of 7 billion, the world’s population has increased by close to 1 billion within 12 years. The UNDESA forecast reveal that by 2050 the population will be 9.3 billion. It is projected that the population will continue to grow, especially in Africa because of high fertility rates (van Bavel, 2013). Energy, water, and food needs, and additional pollution and waste problems increase with the introduction of a new life. These changes are happening at the expense of extinction of wildlife, desertification, rising sea levels, and climate changes. Populations are sustained by natural capital that includes biodiversity, fisheries, forests, soil fertility, minerals and fossil fuels but not sustainable natural income (Emmott, 2013). Cheap water and oil are the major drivers of food supply but oil prices have been on the rise while vital aquifers are been drained by irrigation. Therefore, as the total global population increases the ability of the Earth to sustain people shrinks due to resource depletion. Emmott (2013) states that by 2000 the population was 6 billion, yet pollution was high due agriculture, land use and production, and processing and transportation. Indeed, carbon dioxide in the atmosphere continues to increase because of such activities, and climate change will continue because of population growth-related and excessive resource use activities.
People are inspired by the need to improve, expand, and use more resources in a populous world. The high value placed on people’s lives creates increasing human population, while simultaneously threatening the existence of other species that are seen as not having similar value. PTo sustain large populations, industrialization continues to emphasize mass production from different resources at a faster rate than what is natural. Similarly, energy consumption is directly affecting both plant and animal life through pollution. Issue of overconsumption vs. need?
Norton and Mercier (2016) state how human population was forecast to exceed the world’s carrying capacity and lead to eventual population and economic breakdown. Citing Ehrlich (1968), they argued that by 2000, resources available to humans would deplete, resulting in an increased competition for the meager resources, and perhaps leading to nuclear war, pandemic, and widespread famine. In other words, continuous population growth will lead to crowding and overpopulation that result in excessive resource usage and eventual scarcity. Overpopulation occurs when a species’ population exceeds its carrying capacity in a given geographical area. In that case, the earth’s human population is not overpopulated because resources are not exhausted or are at a level of rendering human population unsustainable. Additionally, it a small portion of the earth’s land is occupied by people, meaning that there is plenty of mass land awaiting settlement. Some scientists argue that when the entire 7.3 billion people are placed in some U.S state like Texas, they cannot overpopulate it to an extent where they cannot survive. Based on this argument, the world cannot be described as overpopulated.
However, economist Thomas Malthus had predicted that human population would grow such that the food supply would not be able to meet demand (Norton & Mercier, 2016). As a result, there would be a shortage of food, terrible famines, and many people would die. Today, the world population stands at 7.3 billion but people still thrive (UNDESA, 2015). From the Malthusian approach, this would not have been possible because of overuse of resources to support everyone. However, countries like Japan, which are not resources-rich, continue to flourish because people are its primary resource (Norton & Mercier, 2016). The problem with Malthusian theory is that at the time of its formulation, neither had industrial development been fully implemented nor the use of fertilizers and pesticides initiated. Technological advancement has helped multiply the quality and quantity of food produced and along with it, the ability for the human population to feed comfortably. Therefore, the world has not been overpopulated.
Unlike the Malthusian theory, under the Marxist theory, population has to be considered by relating it to prevailing mode of production of a society. The Marxist view saw the latter as a representation of the bourgeois view whose aim was maintaining social inequality. Malthus viewed population growth as a recipe for poverty, while Marx blamed it on capitalism (Norton & Mercier, 2016). Therefore, according to Marx, if capitalism is done away with and resources are evenly distributed, then population will not cause poverty. However, while Malthus’s concern was how overpopulation relates to food scarcity, Marx focused on how capitalism was using the surplus to keep wages low and profits high.
Boserup’s theory is concerned with changes and response of subsistence farmers’ societal changes. The argument was that farmers select farming systems that maximize their leisure time and can only change these systems in response to population changes, necessitating increases in food production (Norton & Mercier, 2016). Subsequently, food production technology and innovations will evolve to match the populations’ needs. Increase in population increases the number of mouths to feed while the fear of starvation motivates individuals to improve on the farming methods. As a result, new better and efficient technologies of food production are invented. Therefore, population increase acts as a catalyst that propels production surplus food that can sustain the existing population through agricultural intensification. Based on this approach, it is possible to argue that humans are able to respond promptly to any form of eventuality in the world environment. As long as supply meets demand, the planet cannot be overpopulated. Furthermore, population growth has slowed because of increased use of advanced medicines and access to contraceptives in the developing countries, while it is stagnant or falling in advanced economies.
The demographic transition model discusses changing fertility and mortality rates in the more contemporary world. It postulates that birth and death rates decrease, as life expectancy and living standards increase (Norton & Mercier, 2016). Common social factors associated with these changes include decreased need for children, women’s entry, and desire for formal careers, and late marriages. As a result, the birth rates have been on the decline, especially in the developing economies. In this sense, the decline in population growth has led to a reduction in the chances of overpopulation. In fact, one can argue that population reduction will lead to a revamp of resourcing. The S-shaped curved model, which is an experimental model, is scientific evidence that the population growth process starts slowly, and then gains rapid momentum, before leveling up at the peak. However, in the natural setting such occurrences are unlikely, because there are no controlled conditions. In practice, there tends to be an oscillation between increase and slowdown. In the case of human population, the oscillation may be caused not by nature but by human decision. Therefore, based on this model, the state of a population will be determined by the people.