Ch.1: Environmental Science: An Overview
1.1: Environmental Science defined
Environemtnal science: the study of the relationships in the natural world that occur between
organisms and their environment. It involves all fields of natural science as they bear on the
physical and biological environment → biology, geology, chemistry, physics, and many other
disciplines must be considered when studying environmental science.
Law/principle/paradigm: theories that never display deviation → e.g. law of gravity
Holistic: seeks connections among all aspects of a problem → often a holistic approach in
environmental science.
The input of materials and energy through society is called throughput. Environmental
resources (inputs) are referred to as sources of throughput. Environmental reservoirs that
receive throughput are called sinks. Sinks are the ultimate repository of societal output → can
eventually become input and throughput again.
Input reduction: reducing the flow of materials through society → can control pollution.
This figure identifies the 2 basic causes of most environemtnal probms: human population
pressures and consumption of material goods → increase of both led to increased resource
depletion and pollution.
1.2: The Environment as a System
Biosphere: living organisms of earth
Atmosphere: the gaseous envelope surrounding the planet
Hydrosphere: water on Earth
Lithosphere: rocky matter composing the bulk of the surface of Earth
System: a set of components functioning together as a whole. Systems are composed of
smaller sets of systems made of smaller interacting parts.
3 traits of the global environment:
- Openness → refers to wheter a system is isolated from other system → 2 types:
- Open system: not isolated→exchanges matter and/or energy with other systems
- Closed system: isolated → no exchanges with other systems
- Integration
- Complexity
,Law of Entropy: energy cannot be fully recycled → ‘high-quality’ energy is degraded to
‘lower-quality’ energy→ e.g. atomic energy into heat. Therefore, any system without a renewing
supply from inside or outside will eventually cease to exist.
In terms of energy, Earth is an open system → receives energy from the sun, and expells it in
the form of radiation/heat. In terms of matter, Earth is a closed system.
Complexity: defines how many kinds of parts a system has. Environment has high complexity.
Key traits of the environmental system:
- Moderate integration → transmission of disutrbances from one system to another.
Integrated in the first law of ecology: ‘we can never do merely one thing’ → unintended
consequences.
- High complexity
1.3: what is Environmental Impact?
Environmental Impact: the alteration of the natural environment by human activiy.
- Resource depletion
- Pollution
Can be calculated via: Impact = Population x Consumption
Both population and consumption have grown since the 1900s → resulted in increased
throughput. Overshoot: when too many people live on Earth.
Sustainability: meeting the needs of today’s society without reducting the quality of life for
future generations.
3 strategies can be used to reduce consumption:
- Reduce material needs
- Use less technology to meet our needs
- Use sustainable technology to meet our needs → sustainable technology permits people
to meet their eneds with minimum impact on the environment. 3 ways sustainable
technologies achieve input reduction/conservation:
- Efficiency imporvemnets
- Reuse and recycle
- Substitution
Ecosystem services: the many and varied benefits to humans provided by the natural
environment and from healthy ecosystems. Most ecosystem serives area undervalued or
considered free in the current economic system → environemntal problems can be traced to
market failures. E.g. in the cheap price of gasoline or electricity→ does not include pollution.
Green fees: fees that incorporate the environmental costs of the final product. These promote
conservation of the resource.
, Ch. 2: Human Population Growth
Demography: the study of the size, growth, density, distribution, and other characteristics of
human populations.
2.1: World Population changes over time
Survivorship curve: a graph that shows th epropotion of living indidvuals of each age.3 types
of survivorship patterns:
1. Type I: species spend enormous amounts of time giving care to the young → mortality is
highest as individuals progress into old age (e.g. humans)
2. Type II: species the young, middle, and older generations have an equal chance of dying
3. Type II: species of which parents produce many offspring, when only a few of many
reach old age
Per capita rate of increase: when the birth rate exceeds death rate → can result in either
exponential growth or logistic growth. Envrionmental resustance puts a hold on exponentidal
growth → resources become strained, when carrying capacity is reached → results in an
S-shaped curve with 3 stages:
- Lag phase (=slow growth)
- Exponential phase (rapid growth)
- Levelling of growth.
2.2: Distribution of the Earth’s Human Population
Human population is distributed unevenly over the Earth. Especially in terms of access to and
use of resources. Furthermore, statics such as infant mortality, death rate, longevity vary widely
from country to country between more-developed countries (MDCs) and less-developed
countries (LDCs).
2.3: Age structures
Age structures: differ between populations, countries, or even regions. Often the age
structures change over time → 3 common structures:
- MDC (More developed country) → can be in 2 ways:
- Flat, uniform age structure
- Decreasing in younger ages
- LDC (Less developed country) → skewed towards the younger categories → pyramid
This population will continue to increase in size due to population momentum
Life expectancy: the age to which you expect to live is highly dependent on the region of the
world in which you are born. Lowest life expectancy in the Sub-Saharan region. Infant
mortality: number of child deaths per 1000 infants → drops each year since 2009. Low life
expectancy and high infant mortality in the Sub-Saharan region correlated with HIV/Aids which
is active in this region.
6 diseases are responsible for 90% of total deaths due to communicable diseases:
- Pneumonia, tuberculosis, diarrhea, HIV/AIDS, measles, and malaria
1.1: Environmental Science defined
Environemtnal science: the study of the relationships in the natural world that occur between
organisms and their environment. It involves all fields of natural science as they bear on the
physical and biological environment → biology, geology, chemistry, physics, and many other
disciplines must be considered when studying environmental science.
Law/principle/paradigm: theories that never display deviation → e.g. law of gravity
Holistic: seeks connections among all aspects of a problem → often a holistic approach in
environmental science.
The input of materials and energy through society is called throughput. Environmental
resources (inputs) are referred to as sources of throughput. Environmental reservoirs that
receive throughput are called sinks. Sinks are the ultimate repository of societal output → can
eventually become input and throughput again.
Input reduction: reducing the flow of materials through society → can control pollution.
This figure identifies the 2 basic causes of most environemtnal probms: human population
pressures and consumption of material goods → increase of both led to increased resource
depletion and pollution.
1.2: The Environment as a System
Biosphere: living organisms of earth
Atmosphere: the gaseous envelope surrounding the planet
Hydrosphere: water on Earth
Lithosphere: rocky matter composing the bulk of the surface of Earth
System: a set of components functioning together as a whole. Systems are composed of
smaller sets of systems made of smaller interacting parts.
3 traits of the global environment:
- Openness → refers to wheter a system is isolated from other system → 2 types:
- Open system: not isolated→exchanges matter and/or energy with other systems
- Closed system: isolated → no exchanges with other systems
- Integration
- Complexity
,Law of Entropy: energy cannot be fully recycled → ‘high-quality’ energy is degraded to
‘lower-quality’ energy→ e.g. atomic energy into heat. Therefore, any system without a renewing
supply from inside or outside will eventually cease to exist.
In terms of energy, Earth is an open system → receives energy from the sun, and expells it in
the form of radiation/heat. In terms of matter, Earth is a closed system.
Complexity: defines how many kinds of parts a system has. Environment has high complexity.
Key traits of the environmental system:
- Moderate integration → transmission of disutrbances from one system to another.
Integrated in the first law of ecology: ‘we can never do merely one thing’ → unintended
consequences.
- High complexity
1.3: what is Environmental Impact?
Environmental Impact: the alteration of the natural environment by human activiy.
- Resource depletion
- Pollution
Can be calculated via: Impact = Population x Consumption
Both population and consumption have grown since the 1900s → resulted in increased
throughput. Overshoot: when too many people live on Earth.
Sustainability: meeting the needs of today’s society without reducting the quality of life for
future generations.
3 strategies can be used to reduce consumption:
- Reduce material needs
- Use less technology to meet our needs
- Use sustainable technology to meet our needs → sustainable technology permits people
to meet their eneds with minimum impact on the environment. 3 ways sustainable
technologies achieve input reduction/conservation:
- Efficiency imporvemnets
- Reuse and recycle
- Substitution
Ecosystem services: the many and varied benefits to humans provided by the natural
environment and from healthy ecosystems. Most ecosystem serives area undervalued or
considered free in the current economic system → environemntal problems can be traced to
market failures. E.g. in the cheap price of gasoline or electricity→ does not include pollution.
Green fees: fees that incorporate the environmental costs of the final product. These promote
conservation of the resource.
, Ch. 2: Human Population Growth
Demography: the study of the size, growth, density, distribution, and other characteristics of
human populations.
2.1: World Population changes over time
Survivorship curve: a graph that shows th epropotion of living indidvuals of each age.3 types
of survivorship patterns:
1. Type I: species spend enormous amounts of time giving care to the young → mortality is
highest as individuals progress into old age (e.g. humans)
2. Type II: species the young, middle, and older generations have an equal chance of dying
3. Type II: species of which parents produce many offspring, when only a few of many
reach old age
Per capita rate of increase: when the birth rate exceeds death rate → can result in either
exponential growth or logistic growth. Envrionmental resustance puts a hold on exponentidal
growth → resources become strained, when carrying capacity is reached → results in an
S-shaped curve with 3 stages:
- Lag phase (=slow growth)
- Exponential phase (rapid growth)
- Levelling of growth.
2.2: Distribution of the Earth’s Human Population
Human population is distributed unevenly over the Earth. Especially in terms of access to and
use of resources. Furthermore, statics such as infant mortality, death rate, longevity vary widely
from country to country between more-developed countries (MDCs) and less-developed
countries (LDCs).
2.3: Age structures
Age structures: differ between populations, countries, or even regions. Often the age
structures change over time → 3 common structures:
- MDC (More developed country) → can be in 2 ways:
- Flat, uniform age structure
- Decreasing in younger ages
- LDC (Less developed country) → skewed towards the younger categories → pyramid
This population will continue to increase in size due to population momentum
Life expectancy: the age to which you expect to live is highly dependent on the region of the
world in which you are born. Lowest life expectancy in the Sub-Saharan region. Infant
mortality: number of child deaths per 1000 infants → drops each year since 2009. Low life
expectancy and high infant mortality in the Sub-Saharan region correlated with HIV/Aids which
is active in this region.
6 diseases are responsible for 90% of total deaths due to communicable diseases:
- Pneumonia, tuberculosis, diarrhea, HIV/AIDS, measles, and malaria
