ESS 002- Study Guide for Exam 1  

What is a simple definition of sustainability?

Chapter 1- What is sustainability?  

Sustainability and Sustainable Development Definition  

• Sustain + ability → ability to sustain  

• Enduring into long-term future  

• Sustainable development meets the needs of the present without compromising the ability of  future generation to meet their own needs  

Current State of the Earth  

• Over- exploitation of natural resources  

• Economic & demographic growth  

• Market failure

• Hidden environmental costs are not reflected in market prices  

What are some human activities that degrade natural capital?

• Accelerating resource depletion, waste generation, and environment pollution  • Shorten product lifecycles (technology advances) and changing lifestyles since industrial  revolution  

Environmental Destruction and Degradation  

Wasting, depleting, and degrading the earth’s natural capital  

• Happening at an accelerating rate If you want to learn more check out What does the 360 degree feedback assess?

• Also called natural capital degradation 

What 3 factors determine the resilience of an ecosystem?

Resilience  

≠ Sustainability  

• Capacity of a system to absorb disturbance and retain its basic function and structure

Fundamental Concepts  

Systems: interconnected parts  

Whole greater than sum of its parts:

• Closed loops- no waste  

• Networks and connections  

• Diversity  

• Constant flows  

Natural capital: environmental stock or resources of earth that provides goods, flows, and ecological  services required to support life  

• Examples: minerals, water, waste assimilation, carbon dioxide absorption, biodiversity…  Planetary “savings account”  

Triple bottom line:  

• Three pillars of sustainability are connected  Don't forget about the age old question of Which factors influence health according to the biopsychosocial model?
If you want to learn more check out What are the 3 main areas of cognitive development that occur during adolescence?

• Also known as “three E’s”  

Carrying Capacity 

• Maximum number of individuals a given environment can support indefinitely  Ecological Footprint 

• Demand placed on nature for resources consumed and wastes absorbed, expressed as land  area

If you want to learn more check out What stops the stimulation for muscle contraction?
We also discuss several other topics like What were catholics who refused to attend protestant church services called?

Complex Adaptive Systems  

Interconnected systems + complexity  

• Emergent properties: outcome cannot be predicted + can have more than one stable state • Tipping points = critical thresholds: small changes cause state change  • Small increase in average temperature may trigger abrupt, large- scale, and  irreversible changes in the global climate system  

Challenges & Responses  

Challenges Responses

Extinction

Population

• Individual contributions 

➔ Cumulative solutions

Overshoot

• Regenerative era  

• Better quality of life

Pollution

Climate change

If you want to learn more check out How does structure determine function?

Still forming…. Interdisciplinary  

Chapter 2- A Brief History of Sustainability  

Recent History  

• Malthus (1798)

• Population growth  

• Carrying capacity  

• Thoreau (1854)

• Nature as interconnected community  

• Marsh (1864)

• Planet stewardship vs. resource consumption  

• Muir (1908)  

• National parks (Yosemite)  

• Sierra Club  

• Arrhenius  

• Climate change caused by industry  

Early 20th Century  

Lacey Act of 1900:  

• Response to birds killed for fashion  

• Early wildlife protection  

National Wildlife Refuges  

• Theodore Roosevelt 1904  

For many scientists and policymakers:  

Nature conservation → resource depot for human use  

Science and Ecology  

Ecology focuses on relationships and connections within:  

• Organisms  

• Plant community like a complex living organism  

• Organisms and environments  

• Transfer of energy: food web, food pyramids and trophic levels ‘ • Ecosystems  

• Unpredictability and uncertainty ???? nature is not a machine  

Key terms  

Organism 

• An individual animal, plant, or single-celled life form  

Environment 

• All the living and nonliving external conditions that affect and interact with  organisms, populations, or other living systems

Ecosystem 

• A system of living organisms interacting with each other and their physical  environment  

The Beginnings of the Environmental Movement  

1960s and 1970s  

Rachel Carson’s book “Silent Spring” 1962:  

• Reported the destructive effects of pesticides on the environment  ➔ DDT banned in 1972!  

“The Population Bomb”, 1968 by Paul Ehrlich  

• Exponential human growth causes environmental impacts  

“Small is Beautiful”, 1973 by E.F. Schumacher  

• Perpetual economic growth is not sustainable  

First Earth Day: 1970  

20 million participants nationwide  

???? Rachel Carson’s & others’ activism  

???? environmental accidents e.g. 1969 fire on the Cuyahoga River (Ohio)  Arab Oil Embargo, 1970  

First “Energy Crisis”  

Love Canal, 1978

Community near the Niagara Falls on a former waste site of a chemical company  

• Lots of miscarriage, birth defects, childhood cancer  

• Superfund, 1980  

Key term  

Superfund 

• A US federal government program designed to fund the cleanup of toxic wastes  Environmental Justice  

United Farm Workers organized, 1962  

• Protection against pesticide exposure for farm workers

• Cesar Chavez, Dolores Huerta  

1982: PCB landfill proposed in Warrant County, North Carolina  

• African American neighborhood (minority)  

• Protests and marches  

• Raised awareness  

• Environmental Racism  

• Waste sites located in minority communities in most cities in the U.S. U.S. Legislation in the 1970s  

• 1970  

• Clean air act  

• National environment al policy act (NEPA)

• 1973  

• Endangered Species Act  

• 1975

• Energy Policy and Conservation Act

• 1977

• Clean water act  

+ multiple water, energy and pesticide (DDT) regulations  

Environmental Ethics (The Value of Things)  

• Intrinsic value

• A thing has value in itself  

• Instrumental value  

• A thing is valuable insofar as its benefits humans  

Expanding to a Global Scale  

1972

• Blue marble  

• UN Conference on the Human Environment, Stockholm, Sweden  • “think globally, act locally”

• UN Environment Programme (UNEP) established:  

Importance of triple bottom line

1978, Montreal Protocol

• Global response to thinning of ozone layer  

• Phased out production of CFCs

1988, IPCC (Intergovernmental Panel on Climate Change)  

• Peer-reviewed research & publication the past/present future climatic state  Recent U.N. Major Conferences  

• 1992  

• Earth summit Environment and Development  

• Agenda 21 adopted → healthy economy and environment  

• Un Convention on Biological Diversity adopted  

• UN Framework Convention on Climate Change adopted → Kyoto Protocol  • 2001

• Earth summit

• Millennium Development Goals adopted  

• 2012

• Sustainable Development Goals adopted in 2015  

Modern Trends  

• Bioregionalism  

• Closed loop processes  

➔ Cradle to cradle  

• Green building  

• Sustainability in education  

• Measurement  

➔ Ecological footprint  

➔ Life cycle assessment  

Chapter 3- The Biosphere (The Planet We Live In)  

Matter  

• Anything that occupies space and has mass  

• Examples: solid, liquid, or gas  

• Energy flows through; matter is recycled  

What makes matter move  

• Energy: the capacity to do work  

• Potential energy: stored energy that can be released  

• Kinetic energy: the energy of movement  

➔ Flows one way through a system

Solar Energy: The source of All

Kinetic energy of electromagnetic radiation that powers all the atmosphere, hydrosphere, and  biosphere  

Thermodynamics

• The study of transformation of energy  

• 1st Law: Conservation of Energy  

• Energy cannot be created or destroyed  

• Energy coming in = energy going out  

• 2nd Law: Entropy (disorder) increases  

• High quality energy becomes heat energy  

• Each energy conversion leaves less energy available for work  

The source: Galaxy Cycles  

• Stars= recycling systems  

• 10x10 years life average  

Biogeochemical cycles  

• 24 elements are essential to living organisms  

• Each circulates in a cycle, naturally, precisely balanced  

Natural Water Cycle  

The sun powers the water cycle:  

• Evaporation of the earth’s oceans, lakes, rivers, soil & plants  

• Water vapor rising into the atmosphere  

• Condensation & precipitation  

➔ Water filtration & purification  

World Water;  

>99% oceans, ice, underground, atmosphere  

<< 1% accessible freshwater: lake, rivers, streams…  

~ 90% of the water precipitating on land evaporates/ lost by transpiration  Modified Water Cycle  

Major concerns:  

• More runoff  

• More demand of freshwater  

• Poor irrigation practices  

• Livestock and water pollution

Natural Carbon Cycle  

About all biological molecules- carbohydrates, fats, proteins, DNA… - are composed primarily  of carbon  

Carbon dioxide= key component of the C cycle  

• Important greenhouse has  

• Base of photosynthesis  

Producers (plants) “inhale” it (photosynthesis)  

Consumers(animals) “exhale” it (respiration)  

Modified Carbon Cycle

Major component of fossil fuels  

Major Concerns:  

• Deforestation & fossil fuels burning  

• Greenhouse effect & global climate change  

Natural Nitrogen Cycle  

~78% of the air we breathe is nitrogen (N)  

Some specialized partners in cycle:  

• Lichens: canopy → forest floor  

• Salmon: ocean → river  

• Bear: river → forest soil  

• Bacteria: soil → plants  

Modified Nitrogen Cycle  

Major concerns:  

• Intensive agriculture  

➔ Fertilizer runoff  

➔ Algae bloom  

➔ Loss of oxygen & life in aquatic environment  

• Fossil fuel combustion:  

➔ HN0

➔ Acid rain  

4 Major Interconnected Spheres  

• Geosphere (rock)

• Atmosphere (air)

• Hydrosphere (water)

• Biosphere (organisms)

Geosphere (The Solid Part of the earth)  

• Core (inner and outer)  

• Mantle

• Crust  

Rock cycle  

• Sources of fossil fuels, minerals metal ore • Extraction as big pieces, disposal as little pieces  

Plate tectonic  

• Constantly in motion  

Atmosphere (The Gas Part of the Earth)  

• Regulates conditions for life  

• Constantly in motion  

• Divided in layers  

Hydrosphere (The Liquid part of the Earth)  

• Covers ¾ of the Earth’s surface

• The most abundant substance on Earth’s surface  Oceans ≈ 97% Earth’s water  

• Constantly in motion  

• Driven by the sun

Biosphere (The Living Part of the Earth)  

Layer where life exists, including:  

• Organisms  

• Rocks

• Air  

• Water  

The Biosphere: Life  

Biosphere  

Constant Transfer of Energy and Matter  

• Energy moves through  

• Matter recycles  

Hierarchical Structure of Life  

• Biological entities are organized in a hierarchical structure, ranging from cells to the  biosphere  

Prokaryotes and Eukaryotes  

• Prokaryotes: without nucleus and internal organelles  

• Bacteria  

• Archaea  

• Eukaryotes: everybody else  

• Protists (e.g., algae, protozoa  

• Plants  

• Animals  

• Fungi

What is life?  

Characteristics  

• Membranes

• Metabolism  

• Networks  

• Reproduction  

• Emergence  

• Cooperation e.g., symbiosis  

Emergence and Resilience  

Emergence:  

• Spontaneous appearance of novel properties  

• At system level  

• Not predictable by studying system’s part  

Resilience  

• Capacity of a system to accommodate change  

• But still retain same function and structure  

Symbiosis  

• Evolution of cells with nuclei: mitochondria in cell  • Evolution of plants with photosynthesis: chloroplasts in cell  • Lichens: algae + fungi  

• Coral reefs: algae + anemone  

• Mycorrhizae: roots + fungi  

Bacteria  

The Foundation of Life  

• Primary producers in many food webs

• Essential recyclers  

• Regulate composition of atmosphere  

➔ Invented photosynthesis  

• Constantly communicate with each other  

• Able to metabolize nitrogen, hydrogen sulfide, etc.  

• Some live below freezing  

• Some live above boiling  

What is Life?  

Individual vs. Community  

• Distinction is not always clear

• Examples:  

• Aspen clones  

• Fungus clones  

• Social insects  

• Bacteria  

What is an ecosystem?  

= living organism + their physical environment + interactions and relationships  

= dynamic interactions between plants, animals, and micro-organisms and their environment  working together as a functional unit  

There are two types:  

• Aquatic ecosystem:  

• Exists in a body of water  

• Terrestrial ecosystem  

• Found only on land  

Components

Habitat: the place where organism lives  

where it finds food, shelter, and mates  

Niche: how it earns its living (its function in the community) and how it interacts with the  environment  

How it finds food, shelter, and mates  

Food Pyramids

Most terrestrial ecosystems can’t support tertiary consumers  

???? too small amount of energy available  

In food- poor ecosystems (Mediterranean climate (like California): few animals carnivorous  ???? too small amount of energy available  

→ most are omnivorous eating primarily producers  

Bears, coyotes, foxes….  

Food pyramid, simple approach  

• ~10 times more  

???? 1 trophic level erased  

➔ People must be vegetarians in nation with very large population  

Constant Change  

Disturbance: fire, flood, wind, development

Succession:  

1. Progressive change in response

2. Begins with pioneers  

3. Final stage  

= climax community  

Biomes  

World Distribution  

= major regional habitat type  

• Soil, moisture, climate  

• Distinctive community  

Biodiversity  

Measure of the Variety of Life on Earth  

❖ Variability among living organisms from all sources including, inter alia, terrestrial,  marine and other aquatic ecosystems and the ecological complexes of which they are part  ❖ Includes diversity within species, between species and of ecosystems  

Estimated ~ 10-14 million different species of Earth...

Phytoplankton  

• Remove carbon dioxide to make shells  

• Part of the biological pump  

Emit dimethyl sulphide (DMS):  

• Forms clouds  

• Adjusts albedo (radiation income)  

All Life is Made of Connections  

• Systems within systems  

• Whole always greater than sum of its parts  

Systems  

• System: an integrated whole made of interconnected parts  

• Systems thinking: a way of perceiving reality which considers relationships, processes,  and interconnected parts of the unified wholes  

• Sustainability: the study of systems  

Chapter 4- The Human Sphere (Economy and Ecology)

Human Population Growth  

Exponential Growth  

Human population grows exponentially, not arithmetically  

Cause of the constant growth

3 reasons behind the exponential growth:  

• Human ability to expand and colonize all Earth  

• Progress in agriculture  

• Sanitation & medicinal advance  

Age Structure Helps Predict Future Growth  

• A narrow base → population decline  

• A wide base → rapid future growth  

Age Structure: Population Trends in the United States  

• Population age structure suggests stable size  

• U.S. immigration causes population growth  

Fertility Rate

Total fertility rate:  

• Average number of children a woman gives birth to in her lifetime  Replacement-level fertility:  

• Births required to maintain population size  

Total Fertility Rate Among Countries  

❖ Sub-Saharan Africa have the highest growth rates  

Urban Sprawl

= growth of low-density development on the edge of cities and towns that gobble up surrounding  countryside  

Future  

Growth rate falling but population still increasing  

2050 projection: 9.7 billion  

2100 projection: 11.2 billion  

Demographic transition  

• Shift from high birth rates and death rates to low birth rates and death rate in developed  countries  

• Economic development creates conditions that lead to greater health and lower birth rates  Solutions  

Risk of demographic trap in developing countries:  

• Modern medicine → lower death rates  

• Poverty → birth rate remains high  

Solutions: social/ economic progress  

Women: The True Power!  

Education

Employment Empowerment of young women Reproductive Health  

Social equity → fewer children  

Economy and Ecology

Economics (Concepts)  

• Growth: Quantitative increase  

Sustainable growth = physically impossible  

???? finite biosphere  

• Development: qualitative improvement  

Sustainable development = increase in quality without quantitative growth  • Capital: supply of resources  

Natural capital: ecosystem services+ physical natural resources

Manmade capital: substitutes through technology

Economic Growth  

= linear economy → physically long-tern impossible  

• Releases wastes faster than systems can process them  

• Nonrenewable resources: one they’re gone, they’re gone  

Concepts  

Gross Domestic product (GDP):  

• Indicator of economic progress  

• Measures all economic activity, not well-being  

Index of Sustainable Economic Welfare (ISEW) and Genuine Progress Indicator (GPI)

• Measure economic & social welfare, the costs of environmental damage, pollution,  crime, international debt, income disparity, the benefits of volunteer work & uncounted  household services such as childcare  

• In general, GDP has increased but ISEW and GPI have dropped!  

The Growth Model  

The Drivers  

Fossil fuels:  

• High energy, low cost, convenient  

• = > 80% energy use!  

Acquisitiveness:  

Evolutionary adaptation, now out of control  

Globalization:  

• Positive effect on well-being & economic health  

• But equity issues & environmental issues  

The Controls  

World Bank:  

• Loans to developing countries  

 reduce poverty

International Monterrey Fund (IMF):  

• Monitors currency exchange rates

• Oversees loans  

• Restructures debts between nations  

World Trade Organization (WTO):  

• Eliminate political barriers  

• Improve the free flow of goods/ capital between countries  

Economics Models  

Classical economics: macroeconomics  

• Economy as a whole, production of goods and services as the key focus  Neoclassical economics: microeconomics  

• Power of the market → choose/develop the optimal alternative, the exchange of goods  and services as the key focus  

Environmental economics: subset of neoclassical  

• Society depends on ecosystem services → assign values to services  Ecological economics: economics + ecology + thermodynamics  

• Macroeconomy as a subsystem nested within the biosphere upon which it depends  • Steady- state economy in dynamic equilibrium at an optimal scale  

Ecosystem Services  

Supporting life on Earth:  

• food/water

• oxygen

• habitat  

• nutrient recycling  

• material/resources

Regulate environment:  

• air & water filtration  

• temperature regulator  

• species interactions  

• biogeochemical cycles

Educate/ entertain society  

Externality  

= cost external to entity creating damage, cost of damage not reflected in price

Example: Chinese government analysis for the Yangtze River basin: flood control services of  forests worth 3X more than value of cut timber (3700 dead, 15 million homeless, $26 billion lost

Human Impact  

Environmental Impact  

I = P × A × T  

I; Impact  

P: Populations  

A: Affluence (consumption per capita)  

T: Technology  

Ecological Footprint  

• the per capita land area required for the natural resources consumed  

Carrying Capacity  

= maximum number of individuals a given environment can support indefinitely Results from the Growth Model  

Failing States  

• Failed state = state in which ability to govern has broken down  

• Failing state = state in the process of disintegration  

Often cause of (inter)national conflicts

Indicators  

Social indicators:  

• Demographic pressure

• Refugees  

• Human flight  

• Group grievances  

Economic indicators:  

• Inequality  

• Economic decline  

Political indicators:  

• Illegitimate government  

• Deteriorating public services

• Human rights violations  

• Elite security apparatus  

• Factions  

• Outside intervention

A New Paradigm  

Circular economy:  

• closed-loop consumption <— reuse & recycle  

Decoupling:  

• development without increases in environmental impact

consuming resources < natural rate of renewal  

End of fossil fuel economy —> renewable sources  

Law and policy changes

• true-value price, cheaper green solutions, cap & trade systems, shifting taxes  Equitable distribution

Working Together to Achieve Common Goals  

= process of decision-making to regulate activities and exercise control over resources  

Social inclusion + economic opportunity + healthy ecological function + good governance → sustainability  

Required:  

• accountability → report system’s status  

• transparency → available report  

• participation → all participates in decision-making  

• feedback loop → clear communication  

The Tragedy of the Commons  

Common pool resources (forests, fisheries, aquifers…):  

• from which it is difficult to exclude or limit users  

• use of resources by one person decreases benefits for other users  

Impact on People  

• well-being increases with income only up to a point and beyond that point stops  increasing

• if a society gives up the economic growth model and reaches a sustainable economic  balance, its citizens may not have to sacrifice greatly in terms of happiness  

Chapter 6- Water (Consumption)  

Water on Earth  

Some Facts  

➢ covers ~70% of the Earth’s surface  

➢ the most abundant substance on Earth’s surface  

➢ 3 phases on Earth’s surface: solid, liquid, gas  

➢ The basis of life (with CO2):  

Photosynthesis → base of the food chain  

Distribution  

Freshwater available for use is a small % of total water:  

<1% of the world water

Hydrologic Cycle  

Fluxes of Water Between Reservoirs  

• Water constantly recycles  

• Volume does not change  

• Renewable resource

Water Residence  

• Some recirculates within days  

• Some residence time measured in 1000s of years

Uneven Distribution  

= demands not met because of: uneven distribution, overuse, pollution  Future  

Effects of Climate Change  

Greater flooding; increased drought  

Glaciers shrinking  

—> meltwater source disappearing

Groundwater  

Water Below Our Feet

= substance water contained in pore spaces in unconsolidated rocky material and bedrock  

• Unsaturated zone: mix of air & water  

• Saturated zone: saturated with water  

• Water table: top of saturated zone  

Groundwater Overdraft  

= groundwater withdrawn exceeding water deposition from rainfall and snow melt  ➔ Land subsidence

Seawater Intrusion in Coastal Areas  

Over pumping → saltwater intrusion  

Depletion of Aquifers  

➔ Loss of biodiversity  

Dams: 20% of California’s Electricity  

• Altered flows  

• Damaged ecosystems  

• CH4 emissions from trapped sediments

Sectors of Consumption  

Heavy consumption by:  

• Agriculture  

• Power plants  

• Manufacturing  

Virtual Water  

= total amount of embedded water, also called water footprint  

Higher on food chain = greater virtual water content  

Daily water Needs

- Humans need ~50 L of water per day

Bottled Water  

Questionable quality  

Energy and resource consumption: 3-gal virtual water to make…  1 gal bottled water!  

Plastic bottles:  

• made of petroleum  

• sent to landfills  

• pollution when incinerated  

• harmful to marine wildlife  

Part 2 - Water: Consumption and Solution  Commercial Water Conservation  

Water Efficiency Program  

CII = Commercial + Institutional + Industrial sites  

Cooling systems: major CII water consumers  

Complex water audits by:

• Water conservation technicians or  

• Water service companies (WASCOs)

Residential Water Conservation  

• Water audit:

- The first step

• Technical measures

- Water-saving fixtures  

- Water-efficient landscapes

• Behavioral measures supported by:  

- Mailings  

- Educational programs  

- Water audits  

Domestic Water Use  

Domestic water:  

• Fixtures: toilets, showerheads, faucets

• Appliances: clothes washers, dishwashers

Toilets  

Residential:  

- 5.1 flushes / person / day  

Work place:  

- 3 flushes / person / day  

Must be low-volume:  

• Low-volume toilet: ~1.6 gallons per flush (gpf)  • Dual-flush toilet: ~1.6 gpf solid waste

 ~0.8 gpf liquid waste

• Urinal: ~1.0 gpf maximum

(Toilets before 1992 were 3.5-7.0 gpf)

CLOTHES WASHERS, SHOWERHEADS AND FAUCETS 2nd largest domestic use: Clothes washers  

• 0.37 load / person / day  

• High-efficiency washers: 27 gallons per load (gpl) (older models: 35 gpl)  

3rd largest domestic use: Showerheads and faucets  

• Must be low-volume: 2.2 - 2.5 gallons per minute (gpm)  • (Showerheads before 1992 were 3.0-8.0 gpm)

LANDSCAPES

In US West, ~70% of residential water goes to grass  Reduction through:  

• Use native or regionally adapted plants; avoid lawns  • Use mulch, leaves to retain moisture  

• Use drip irrigation

AGRICULTURE

World’s largest consumer of water:  

• 70% of the world water usage  

• 41% of the U.S. water usage Conventional irrigation:  most runs off, never taken by plants!

Organic farming: moisture is retained

Collecting from the Sky  

1. Collect rainwater  

2. Store  

3. Use late

Components (Rainwater Harvesting)  

Catchment area

- roof  

Conveyance

- gutters, pipes, downspouts  

Filtration  

- Roof washer, First flush: when rain first falls  on the roof it carries the majority of the  debris and pollutants with it.  

Storage

- cistern, tank  

Distribution

- gravity or pump  

Purification for potable (drinkable) use

- Filtration, UV disinfection, pH buffering

GRAYWATER (PARTIAL ALTERNATIVE TO RAINWATER)

Wastewater from bathroom sinks, showers, bathtubs, clothes washers  

Not kitchen sinks or toilets  

Some jurisdictions allow graywater for nonpotable uses  

Can be used for:  

➢ toilets  

➢ irrigation  

➢ cooling-tower makeup water

➢ fire suppression systems

BLACKWATER

• In black pipes, NOT mixed with graywater  • Purified through biological method  

• Used for irrigation or released in rivers USING NATURAL SERVICES

Primary sewage treatment: physical process:  

➢ large floating objects removed  

➢ heavier material settles to the bottom of tanks ➔ form solids  

➔ landfills  

Secondary sewage treatment: biological process  

➢ bacteria degrade  

➢ dissolved waste removed  

➢ bleaching (chlorine)

➔ kill bacteria  

➔ water is released back into the environment Stormwater  

Some intercepted by leaves, branches  

Some infiltrates into soil  

Some collects in pockets  

Remainder runs off surface: runoff

Sustainable Stormwater Strategies  Think small  

Start at the source  

Maximize permeable surfaces  

Rain garden:

• vegetated depression  

• cleanses, infiltrates stormwater

Bioswale:  

• Vegetated linear depression  

• Cleanses, infiltrates stormwater  

Porous paving:

• Rock-filled reservoir with porous surface  

• Cleanses, infiltrates stormwater  

Chapter 7- Ecosystems and Habitats: Extinction  

Population  

= group of individuals of a species living together and interacting regularly in an area  

Over time a population may increase, decrease, remain about the same or go up and down in  cycles.  

Key features:  

- Size  

- Density  

- Dispersion  

- Age structure  

- Dynamics  

Size and Density  

Size:  

• Number of individuals in a population at given time  

• Controlled by births, deaths, immigration & emigration  

Density: number of individuals per unit area (or unit volume)  

Biological Extinction  

Extinction of Species  

= permanent loss of any species from Earth  

Background extinction: every species become extinct  

~ 1 species lost over 1 million species/ year  

Mass Extinctions  

When ~25-95% of all species on the are wiped out in one catastrophic event  → biodiversity increases over time, but each recovery required millions of years  

→ opportunity for the evolution of new species that can fill unoccupied ecological roles or  new ones  

Threatened and Endangered Species

• Threatened (or vulnerable) species  

• Endangered species  

• Threatened (or vulnerable) species:  

➢ Still enough remaining individuals to survive in the short term  ➢ But declining numbers  

→ likely to become endangered  

Polar bears, giant panda, sea turtle…

• Endangered species:  

➢ So, few individual survivors  

→ species soon to be extinct  

Tiger, whale, orangutan…  

Past Extinctions  

Geological records: 5 mass extinctions over the last 500 million years  Drivers of Ecosystem Change  

HIPPO  

H - Habitat destruction  

I - Invasive species  

P – Pollution  

P – Population  

O – Overexploitation  

HUMAN

Human have:  

• taken over 60-80% of the Earth’s land surface

• polluted & disturbed 50% of the oceans & surface waters Primary Drivers of Extinction

Habitat Destruction  

- clearcutting  

- bottom trawling  

- urban development  

- agriculture  

- fragmentation

Invasive Species  

➢ Introduced outside its normal distribution  

➢ Outcompetes native species  

➢ Nonnatives are not necessarily invasive

Pollution  

- sometimes visible and sometimes invisible  

HUMAN POPULATION  

Human (come with) = highly adaptable invasive species  

Typical pattern:

extinctions follow human settlement

Orangutans  

1900: 315,000 wild orangutans in the tropical forests of Indonesia and Malaysia  Now fewer than 30,000 <— 2,000 reduction every year  

Likely to be the first great ape species to go extinct due to mankind’s direct actions  Why?  

- Palm oil plantations clear the forests  

- Smuggled orangutans sell for $10,000 on the black market  

- Bush meat: any terrestrial mammals, birds, reptiles and amphibians harvested for food  Part 2- Ecosystems and Habitats: Protection  

THEMES

Structural complexity

- Diversity in vertical structure  

➔ horizontal structure  

➔ age structure  

More species living in an ecosystem —> more stable

Connectedness  

Interconnection between organisms and environment

Disturbance  

- temporary change in environmental conditions that causes a pronounced change in an  ecosystem  

Resilience  

- Capacity of an ecosystem to adapt from a disturbance

THE FIRST LINE OF DEFENSE FOR PRESERVING BIODIVERSITY

Creation of protected places: reserves, refuges, parks, private lands  

Too many threatened BUT too few resources!  

➡Which ecosystem to protect —> the 4 R  

• Representation: contains as many aspects of biodiversity as possible  • Resiliency: large & intact enough to resist disturbances  

• Redundancy: enough species to avoid empty niches due to extinctions  • Reality: sufficient funding & political will —> monitoring, managing

SPECIES APPROACH

Priority will be given to:  

• Endangered species 

• Indicator species: indicate particular environmental conditions 

• Keystone species: its removal can cause major disruption of the ecosystem • Flagship species: so charismatic that it generates public support  

• Umbrella species: protecting it also protects other habitat sharing species ECOSYSTEM APPROACH

Most essential organisms not visible

—> more effective to protect healthy, intact ecosystems rather than species

Done through strategies for the integrated management of land, water and living resources  (Habitat Conservation Plans)

HOTSPOT APPROACH

34 identified worldwide areas where greatest diversity of species facing highest risks of  extinction (vs. 25 biodiversity hotspots)

PROTECTION STRATEGIES

Land trusts:  

• nonprofit organization  

• get or help getting land or help on conservation easements  

• provide stewardship  

Conservation easements:  

• landowner keeps ownership  

• no building nor land exploitation  

Mitigation:  

• can destroy a resource if similar resource is created/restored another site  • or monetary compensation

THE SECOND APPROACH FOR PRESERVING BIODIVERSITY

Ecological restoration is the process of assisting the recovery of an ecosystem that has been  degraded, damaged, or destroyed.  

Long-term commitment: constant monitoring and adjustments  

Question: restore to when?  

• Managed park or functioning ecosystem?  

❖ Ecosystems at all scales change constantly over time!

TERRESTRIAL SITES

Forests, prairies, wetlands  

• Remove barriers  

❖ grazing, pollution, roads, invasive species  

• Allow natural processes to operate

❖ controlled disturbance to recreate complexity  

❖ controlled fires, soil excavation, replanting native species…

FROM HUMANS LIVING IN THE ENVIRONMENT TO THE ENVIRONMENT LIVING  WITHIN HUMANS!

❖ Yards and parks  

- a place that functions as a healthy ecosystem  

❖ Bird nesting  

- utility pole, chimneys, rooftops…. as places for bird nests  

❖ Bat roosting  

❖ Green roofs  

❖ Cemeteries  

❖ Golf courses  

❖ Public lands  

❖ Military sites  

❖ Farmland