Overpopulation is the state whereby the human population rises to an extent exceeding the carrying capacity of the ecological setting. In an overpopulated environment, the numbers of people might be more than the available essential materials for survival such as transport, water, shelter, food or social amenities. This regularly contributes to environmental deterioration, worsening in the quality of life, or even the disintegration of the population.
It is estimated that about 81 million people add to the world’s population annually. Regions with the highest number of population density (the number of people living in a given region) feel the dire effects and problems of overpopulation. Due to immigration, the decline in mortality rates, medical breakthroughs, and increased birth rates, populations will always increase and eventually gives rise to overpopulation.
Wikipedia defines overpopulation as,
“Overpopulation occurs when a population of a species exceeds the carrying capacity of its ecological niche. Overpopulation is a function of the number of individuals compared to the relevant resources, such as the water and essential nutrients they need to survive. It can result from an increase in births, a decline in mortality rates, an increase in immigration, or an unsustainable biome and depletion of resources.“
Problems of Overpopulation
Overpopulation thus contributes to some of the most compelling environmental problems which encompass:
- Depletion of Natural Resources
As human population keeps on enlarging, exhaustible natural resources such as arable land, coral reefs, fresh water, fossil fuels, and wilderness forests continue to drop sharply. This creates competitive demands on the vital life-sustaining resources and contributes to an incredible decline in the quality of life.
According to a study by the UNEP Global Environment Outlook, excessive human consumption of the naturally occurring non-renewable resources can outstrip available resources in the near future and remarkably deplete them for future generations.
- Accelerated Habitat Loss
The increased loss of the ecosystems including wetlands, wildlife, rainforests, coral reefs, aquatic life forms, and grasslands are highly influenced by overpopulation. It is out of overpopulation that activities such as excessive agriculture, environmental pollution, and extensive land development have become more and more intensive.
For example, rainforests originally covered 14% of the entire earth’s surface. Today, rainforest only cover about 6% of the earth’s surface and scientists’ project it may even become less in the next four decades judged by the current rate of vegetation removal, logging, and deforestation. Besides, due to environmental pollution, 30% of the ocean reefs have been lost because of acidification and global warming since 1980. Also, more than half of the original wetlands have been lost.
- Amplified Climate Change and Global Warming
Because of overpopulation, it means more and more population. The more the number of people, the more the number of vehicles and industries as well as air travels. Furthermore, more population translates to increased use of energy sources such as coal and firewood which contributes to increased greenhouse gas emissions.
Hence, because of the accumulation of human-generated greenhouse gasses and carbon footprint in the atmosphere, the planet has continued to witness amplified global warming and climate change. The effects of climate change and global warming are profound resulting in extreme hunger, drought, flooding, and habitat loss to an extent of threatening the survival of human civilization.
- Loss of Biodiversity
Overpopulation has seen continued encroachment into frontier forests, heightened pollution, and destruction of natural ecosystems that has greatly contributed to the mass extinction of species. The number of threatened species persists to multiply worldwide whereas some have completely gone extinct.
This is because of the human activities such as acidifying water systems, over-exploitation of natural resources, pollution, over-fishing, poaching, and the deliberate as well as the indirect destruction of natural systems necessary for the survival of different species. These human activities simply alter the natural process combined, thus, destroying the natural ecosystems supporting biodiversity.
- Depreciation of Fresh Water
The unrelenting nature of overpopulation on earth has destroyed most of the world’s freshwater systems. Most of the lakes, streams, rivers and groundwater making up fresh water have been made unreachable or become too polluted. According to the global outlook of water resources, these activities influenced by overpopulation have only left less than 1% of the planet’s freshwater readily accessible for human utilization.
Water vulnerability is already affecting many overpopulated nations, especially in some developing countries, as the demands for water tend to be more than the accessible water. Millions of fish species from freshwater ecosystems are on the verge of extinction. Thus, as human inhabitants rise in number, so will the problem of quality freshwater accessibility.
- Lower Life Expectancy and Diminished Quality of Life
Overpopulation lowers the standards of living since it creates stress on the vital resources for survival and increases the difficulty of accessing the consistent supply of quality food, water, energy, health, security and shelter. Consequently, it makes the poor to become poorer, and they often opt for poor living conditions to survive.
Eventually, it gives rise to lower life expectancy. The situation is serious in developing nations such as southern Asia and sub-Saharan Africa where most of the poor populations submit to inadequate and poor diets.
- Emergence of New Pandemics and Epidemics
According to WHO, overpopulation is one of the leading causes of the speedy occurrence and emergence of human diseases. Overpopulation worsens numerous environmental and social factors such as pollution, malnutrition, overcrowded living conditions, and lacking health care which makes poor communities vulnerable to infectious diseases. Diseases such as tuberculosis, malaria, HIV, and dysentery spread faster in overpopulated areas.
- Intensive Farming Practices
In regions where populations are high, people resort to farming practices that can produce more food products with cheaper inputs and without encroaching into surrounding lands due to the recent environmental protection policies. Intensive farming has thus resulted, and it has led to soil fertility depletion, re-emergence of parasites, the emergence of new parasites, loss of ecosystems, pollution of water systems, and decreased biodiversity.
- Rise in Unemployment, Crime Rate, and Violence
In overpopulated nations, the available jobs are fewer than the overall job seeking population. This contributes to high levels of unemployment. In turn, lack of unemployment leads to elevated crime rates because of theft, drug cartels, and militia groups which are exploited as options for attaining basic resources and necessities such as food, good living standards, and wealth. Violence and conflicts arise when people start competing for the available limited resources.