Concepts of Environmental Science
Human Populations
Population growth is the increase in the number of individuals in a population.
Every second, on average, four or five children are born somewhere on the earth. In that same second,
one or two other people die. This difference between births and deaths means a net gain of about 2.5 more
humans per second (on average) in the world’s population.
World population: ~7.8 billion
Philippines: ~109 million
- 13th most populous
- “Young” population
Factors contributed to the rapid population growth:
- Increased sailing and navigating skills stimulated commerce and communication among nations.
- Agricultural developments, better sources of power, and improved health care and hygiene
also played a role.
- We are now in an exponential, or J curve, pattern of growth.
Perspectives on Population Growth
Causes and Consequences of population growth
Malthus – Thomas Malthus collected data to show that populations tended to increase at
an exponential, or compound, rate, whereas food production either remained stable or increased
only slowly. Eventually, he argued, human populations would outstrip their food supply and
collapse into starvation, crime, and misery.
Marx – Karl Marx presented an opposing view that population growth results from
poverty, resource depletion, pollution, and other social ills. Slowing population growth, claimed
Marx, requires that people be treated justly, and that exploitation and oppression be eliminated
from social arrangements.
Both Marx and Malthus developed their theories about human population growth when
the world, technology, and society were understood much differently from how they are today. In
this view, birth control should be our top priority.
Technology
- increases carrying capacity for humans (more food production, improved engineering and
sanitation).
Our environmental effects aren’t just a matter of sheer population size; they also depend on what
kinds of resources we use and how we use them.
This concept is summarized as the I = PAT formula.
Human Populations
Population growth is the increase in the number of individuals in a population.
Every second, on average, four or five children are born somewhere on the earth. In that same second,
one or two other people die. This difference between births and deaths means a net gain of about 2.5 more
humans per second (on average) in the world’s population.
World population: ~7.8 billion
Philippines: ~109 million
- 13th most populous
- “Young” population
Factors contributed to the rapid population growth:
- Increased sailing and navigating skills stimulated commerce and communication among nations.
- Agricultural developments, better sources of power, and improved health care and hygiene
also played a role.
- We are now in an exponential, or J curve, pattern of growth.
Perspectives on Population Growth
Causes and Consequences of population growth
Malthus – Thomas Malthus collected data to show that populations tended to increase at
an exponential, or compound, rate, whereas food production either remained stable or increased
only slowly. Eventually, he argued, human populations would outstrip their food supply and
collapse into starvation, crime, and misery.
Marx – Karl Marx presented an opposing view that population growth results from
poverty, resource depletion, pollution, and other social ills. Slowing population growth, claimed
Marx, requires that people be treated justly, and that exploitation and oppression be eliminated
from social arrangements.
Both Marx and Malthus developed their theories about human population growth when
the world, technology, and society were understood much differently from how they are today. In
this view, birth control should be our top priority.
Technology
- increases carrying capacity for humans (more food production, improved engineering and
sanitation).
Our environmental effects aren’t just a matter of sheer population size; they also depend on what
kinds of resources we use and how we use them.
This concept is summarized as the I = PAT formula.
