Biology Lecture Notes
Introduction to Ecology and Sustainability
WHAT IS ECOLOGY?
• The study of the interactions between organisms and their environment
• It is considered the fundamental environmental science
NATURAL SELECTION
• Charles Darwin proposed that the environment favours certain genotypes
that enables some organisms to survive longer in certain environments
• This creates a process known as ‘survival of the fittest’
FUNDAMENTAL REQUIREMENTS FOR ORGANISMS
• Most organisms prefer to reside in a niche environment
• Living organisms feed off natural resources for energy
ECOSYSTEMS
• An ecosystem is an independent community of organisms interacting
with its environment
• There is an energy and chemical flow occurring within each ecosystem
• Each ecosystem has a degree of biodiversity, which is the different
variations of organisms in terms of genetic quality and species count
ENERGY FLOW
• Every ecosystem has a trophic (feeding) structure that determines the
flow of energy between organisms
• Primary producers are autotrophic plants which photosynthesis to
retrieve energy from sunlight, which commences the trophic system
CASE 1: LAND CLEARING IN AUSTRALIA
• Environmental issues:
o Clearing of wooded areas
o Impacts on ecosystem functionality and biodiversity
• Effect on environment:
o Destruction of habitats for animals and vegetation communities
• Role of environmental science:
o Measure extent of land clearing
o Estimate impacts on ecosystems and biodiversity
o Ascertaining the regrowth of vegetation
RATES OF EXTINCTIONS
, • 127 confirmed species of birds have become extinct since the 17 th
century and there are guessed to be several hundred more
o Humans are estimated to have caused 20% of this destruction
o There are currently 9800 species of birds on Earth, down from a
peak of around 13000
• Global fishing industry output increased 6-fold between 1950-1997,
leading to around 60 fish species extinctions
• The loss of biodiversity is an issue due to:
o Contributes to regulating ecosystems which benefit humans
directly
o Disrupts the trophic process for human societies who rely on
catching and hunting their own food
o Allows for medicines to be produced
o Stabilises air and water quality
THE ISSUE OF RISING POPULATIONS
• The world population has reached around 8 billion, rising exponentially
particularly in developing countries
• Natural increase is the difference between birth and death rates, giving
the annual rate of population increase
• Fortunately, the rate of population growth has receded to around 0.9%
from a peak of 2.1% in the 1960s
• Studies show that increased primary and secondary education leads to
decreasing fertility rates in women
• The rising population is an issue due to:
o Leads to increased pressure on natural resources
o Limited space on Earth
• The current human population is currently demanding 140% of what is
sustainable on Earth
CASE 2: PLASTIC LITTER
• Environmental issues:
o Plastic pollution of oceans
o Microplastic contamination
, • Effects on environment:
o Harms or kills animals when ingested
o Consumed by humans through commercial seafood
• Role of environmental science:
o Measuring extent of plastic pollution
o Estimating impacts on biodiversity
o Provide solutions to minimizing plastic litter
INTRODUCTION TO SUSTAINABILITY
• Sustainability is the preservation of natural resources whilst balancing a
reasonable quality of life
• Various sustainability awareness events have been successful in:
o Raising public awareness
o Gaining private industry interest
o Improvement of environmental situation
o Foundation of an international cooperation
• These same events have failed in terms of:
o Gaining international funding
o Receiving national commitment
o Attaining solid leadership
• Global sustainability goals have been created for each year of the future
SUSTAINABILITY AND ECONOMICS
• Economic sustainability and environmental sustainability are often
mutually exclusive
• Gross Domestic Product (GDP) is the total value of all goods and
services produced in a country across an entire year
• The Genuine Progress Indicator (GPI) actually factors into account the
environmental degradation as a result of economic activity
• On average in the USA, a family wastes around $600 worth of food each
year
• Natural capital is any stock of natural resources that produces goods and
services for the economy
• Sustainable development is the advancement of society that does not
degrade the environment over the next century
• Civilization is not sustainable for the largely the following reasons:
o Resource scarcity
o Environmental issues
o Poverty
o Conflict between nations
o Falling standards in environmental protection
CASE 3: SOUTH AUSTRALIAN POLICY
• Environmental policy:
o Habitat loss and degradation
o Climate change
o Invasive species
o Overharvesting
Introduction to Ecology and Sustainability
WHAT IS ECOLOGY?
• The study of the interactions between organisms and their environment
• It is considered the fundamental environmental science
NATURAL SELECTION
• Charles Darwin proposed that the environment favours certain genotypes
that enables some organisms to survive longer in certain environments
• This creates a process known as ‘survival of the fittest’
FUNDAMENTAL REQUIREMENTS FOR ORGANISMS
• Most organisms prefer to reside in a niche environment
• Living organisms feed off natural resources for energy
ECOSYSTEMS
• An ecosystem is an independent community of organisms interacting
with its environment
• There is an energy and chemical flow occurring within each ecosystem
• Each ecosystem has a degree of biodiversity, which is the different
variations of organisms in terms of genetic quality and species count
ENERGY FLOW
• Every ecosystem has a trophic (feeding) structure that determines the
flow of energy between organisms
• Primary producers are autotrophic plants which photosynthesis to
retrieve energy from sunlight, which commences the trophic system
CASE 1: LAND CLEARING IN AUSTRALIA
• Environmental issues:
o Clearing of wooded areas
o Impacts on ecosystem functionality and biodiversity
• Effect on environment:
o Destruction of habitats for animals and vegetation communities
• Role of environmental science:
o Measure extent of land clearing
o Estimate impacts on ecosystems and biodiversity
o Ascertaining the regrowth of vegetation
RATES OF EXTINCTIONS
, • 127 confirmed species of birds have become extinct since the 17 th
century and there are guessed to be several hundred more
o Humans are estimated to have caused 20% of this destruction
o There are currently 9800 species of birds on Earth, down from a
peak of around 13000
• Global fishing industry output increased 6-fold between 1950-1997,
leading to around 60 fish species extinctions
• The loss of biodiversity is an issue due to:
o Contributes to regulating ecosystems which benefit humans
directly
o Disrupts the trophic process for human societies who rely on
catching and hunting their own food
o Allows for medicines to be produced
o Stabilises air and water quality
THE ISSUE OF RISING POPULATIONS
• The world population has reached around 8 billion, rising exponentially
particularly in developing countries
• Natural increase is the difference between birth and death rates, giving
the annual rate of population increase
• Fortunately, the rate of population growth has receded to around 0.9%
from a peak of 2.1% in the 1960s
• Studies show that increased primary and secondary education leads to
decreasing fertility rates in women
• The rising population is an issue due to:
o Leads to increased pressure on natural resources
o Limited space on Earth
• The current human population is currently demanding 140% of what is
sustainable on Earth
CASE 2: PLASTIC LITTER
• Environmental issues:
o Plastic pollution of oceans
o Microplastic contamination
, • Effects on environment:
o Harms or kills animals when ingested
o Consumed by humans through commercial seafood
• Role of environmental science:
o Measuring extent of plastic pollution
o Estimating impacts on biodiversity
o Provide solutions to minimizing plastic litter
INTRODUCTION TO SUSTAINABILITY
• Sustainability is the preservation of natural resources whilst balancing a
reasonable quality of life
• Various sustainability awareness events have been successful in:
o Raising public awareness
o Gaining private industry interest
o Improvement of environmental situation
o Foundation of an international cooperation
• These same events have failed in terms of:
o Gaining international funding
o Receiving national commitment
o Attaining solid leadership
• Global sustainability goals have been created for each year of the future
SUSTAINABILITY AND ECONOMICS
• Economic sustainability and environmental sustainability are often
mutually exclusive
• Gross Domestic Product (GDP) is the total value of all goods and
services produced in a country across an entire year
• The Genuine Progress Indicator (GPI) actually factors into account the
environmental degradation as a result of economic activity
• On average in the USA, a family wastes around $600 worth of food each
year
• Natural capital is any stock of natural resources that produces goods and
services for the economy
• Sustainable development is the advancement of society that does not
degrade the environment over the next century
• Civilization is not sustainable for the largely the following reasons:
o Resource scarcity
o Environmental issues
o Poverty
o Conflict between nations
o Falling standards in environmental protection
CASE 3: SOUTH AUSTRALIAN POLICY
• Environmental policy:
o Habitat loss and degradation
o Climate change
o Invasive species
o Overharvesting
