Ecosystems and Biodiversity Review

Unit 1 - The Living World: Ecosystems

1.1 - Ecosystem Basics

  • Environments can be studied at five different levels. The levels, ranked from smallest to largest, are:

    • Individual

    • Population

    • Community

    • Ecosystem

    • Biome

  • Identify three examples of biotic and abiotic factors that can be measured in ecosystems:

    • Biotic factors: animals, bacteria, fungi, plants.

    • Abiotic factors: sunlight, temperature, precipitation, moisture/water, pH, soil.

  • Symbiosis table describing types of interaction:

    Types of Interaction

    Species 1

    Species 2

    Competition

    –

    –

    Predation

    +

    –

    Mutualism

    +

    +

    Commensalism

    +

    0

  • Identify two types of predation:

    • Herbivore

    • True Predators

    • Parasites

    • Parasitoids

  • Explain how species have evolved to reduce competition. The term used is called resource partitioning. Different species competing for the same resources evolve to use those resources in different ways and/or at different times. Example: Wolves hunt deer during the day whereas coyotes hunt at night (temporal partitioning).

1.2 - Terrestrial Biomes

  • Define a biome: An area that shares a combination of average yearly temperature and precipitation (climate).

  • Biomes are defined by:

    • Climate, specifically annual temperature and precipitation.

  • Use of a figure (not provided) to identify specific biomes:

    • Biome that averages 100 cm of precipitation and 10°C is a Temperate Seasonal Forest.

  • As polar regions of Canada warm, the Arctic Tundra could transition into a:

    • Boreal forest, shrubland, or temperate grassland (most are becoming shrublands).

1.3 - Aquatic Biomes

  • Identify and describe four characteristics of aquatic biomes:

    • Salinity

    • Depth

    • Flow

    • Temperature

  • Two types of freshwater biomes:

    • Rivers

    • Lakes

    • Wetlands (swamps, marshes, bogs)

  • Two types of saltwater biomes:

    • Coral reefs

    • Intertidal zones

    • Open ocean

  • A biome that is both fresh and saltwater is called an estuary (includes salt marsh and mangrove swamp).

1.4-1.7 - Biogeochemical Cycles

  • Difference between a sink and a source in chemical cycles:

    • Sink: A reservoir that stores more than it releases.

    • Source: A reservoir that releases more than it stores.

  • Draw the carbon cycle including the following terms:

    • Photosynthesis

    • Respiration

    • Burial

    • Extraction

    • Exchange

    • Combustion

  • Draw the nitrogen cycle including:

    • Atmospheric nitrogen

    • Fixation (bacterial and synthetic)

    • Assimilation

    • Ammonification

    • Nitrification

    • Denitrification

  • Draw the phosphorus cycle including:

    • Weathering

    • Assimilation

    • Excretion/decomposition

    • Sedimentation

    • Unique characteristic: The phosphorus cycle does not have an atmospheric phase.

  • Draw the hydrologic cycle (water cycle) including:

    • Precipitation

    • Infiltration

    • Runoff

    • Evaporation

    • Condensation

Sinks and Sources for Each Cycle and Importance to Life

Cycle

Sink

Source

Importance to Life

Carbon

Fossil fuels (coal, natural gas)

Combustion

Carbon-based lifeforms need carbon for all biomolecules (proteins, carbohydrates, lipids, DNA).

Nitrogen

Ocean (largest)

Rock weathering

Key chemical in amino acids (proteins).

Phosphorus

Sediment, Rocks

Synthetic fertilizers, sewage runoff

Key chemical in genetic material (DNA).

Water

Ocean (largest), Groundwater (aquifers), Ice caps

Evaporation, Transpiration

Key chemical for sustaining life; all organisms need water to survive.

1.8 - Primary Productivity

  • Define primary productivity: The rate at which solar energy is converted into organic compounds (through photosynthesis) over a period of time.

  • Equation for primary productivity:
    NPP = GPP - RL

    • Unit: kcal/m^2/yr

    • Where:

      • $NPP$: Net Primary Productivity

      • $GPP$: Gross Primary Productivity

      • $RL$: Respiration Loss (sometimes denoted as “R”).

  • Calculations:
    a. Forest with a GPP of 20,000 kcal/m²/year uses 5,000 kcal for respiration:
    NPP = GPP - RL = 20,000 - 5,000 = 15,000 ext{ kcal/m}^2/ ext{yr}

    b. Ecosystem with an NPP of 2,000 kcal/m²/year and producers use 18,000 kcal/m²/year for respiration:
    NPP = GPP - RL
    2,000 = GPP - 18,000
    ightarrow GPP = 2,000 + 18,000 = 20,000 ext{ kcal/m}^2/ ext{yr}

    c. Ecosystem with a GPP of 3.5 kgC/m²/year and NPP of 1.5 kgC/m²/year:
    NPP = GPP - RL
    3.5 = 1.5 - RL
    ightarrow RL = 3.5 - 1.5 = 2.0 ext{ kgC/m}^2/ ext{yr}

  • Three factors impacting overall productivity:

    • Water availability: Essential for photosynthesis.

    • Temperature: Higher productivity occurs at warmer temperatures, sustaining leaf health.

    • Nutrient availability: Essential for growth; lack of nutrients limits productivity. Not included in AP material, but sunlight is also critical: more sunlight equals more photosynthesis and higher productivity.

1.9 & 1.10 - Trophic Levels & The 10% Rule

  • Describe the conservation of matter and energy:

    • Matter is not created or destroyed, only transformed (e.g., glucose breaks down to carbon dioxide).

    • Energy is not created or destroyed, only transformed/transferred (e.g., energy from the sun is used to make food).

    • Second Law of Thermodynamics: Energy transformation results in heat loss.

  • Define the 10% rule:

    • In energy transfer between trophic levels, approximately 10% of energy is transformed into usable energy by consumers; the remaining 90% is lost as heat.

  • Trophic Levels:

    1. Producers

    2. Primary Consumers

    3. Secondary Consumers

    4. Tertiary Consumers

    5. Occasionally Quaternary Consumers (rare).

  • Example calculation of energy at trophic levels:
    a. From grass (10,000 J) to primary producer: Use 10% rule:
    10,000 J imes 0.10 = 1,000 J

1.11 - Food Chains & Food Webs

  • Define a food web: A collection of interconnected food chains, indicating energy and biomass transfer. Arrows represent the direction of transfer.

  • Compare and contrast food webs and food chains:

    • Food Chain: Direct representation of energy transfer among specific organisms.

    • Food Web: Collection of food chains; shows how consumers may feed on multiple species.

  • Define trophic cascade: An ecological event where changes in a top predator's population impact lower trophic levels, leading to significant ecosystem restructuring.

  • Identify trophic levels using the provided diagram (not shown):

    • Lion: Secondary consumer

    • Antelope: Primary consumer

    • Bush: Producer

    • Effects of rhino extinction:

      • Expected rise in tree and grass populations.

      • Increased populations of giraffes, crickets, and mice due to reduced competition for resources.

      • Potential decrease in lion and vulture populations, resulting in a trophic cascade.

Unit 2 - The Living World: Biodiversity

1.1 - Biodiversity Basics

  • Define biodiversity: The variety of life in the world or in a particular habitat or ecosystem.

  • Identify and describe the three levels of biodiversity:

    1. Genetic diversity

    2. Species diversity

    3. Ecosystem diversity

  • Describe richness (r) and evenness in biodiversity figures (not provided).

1.2 - Ecosystem Services

  • Identify four types of ecosystems and examples of each type of ecosystem service:

    1. Provisioning Services (e.g., food, water)

    2. Regulating Services (e.g., climate regulation)

    3. Cultural Services (e.g., recreation)

    4. Supporting Services (e.g., nutrient cycling)

1.3 - Island Biogeography

  • Describe the two basic rules of island biogeography:

    1. Size of the island: Larger islands tend to have more biodiversity.

    2. Distance from the mainland: Closer islands have higher immigration rates.

  • Explain how islands can lead to adaptive radiation: Limited environments on islands can result in species diversifying into many forms to fill various ecological niches.

1.4 - Ecological Tolerance

  • Define ecological range of tolerance: The range of abiotic conditions (e.g., temperature, pH) in which an organism can survive.

  • Identify three abiotic conditions that have a range of tolerance:

    1. Temperature

    2. pH

    3. Salinity

  • Describe and label the three zones of tolerance:

    1. Optimal Zone

    2. Stress Zone

    3. Intolerance Zone

  • Identify organisms that reflect environmental conditions:

    • Examples: Lichens and indicator species (sensitive to changes in pollution).

1.5 Natural Disruptions of Ecosystems

  • Identify three types of disruptions that affect ecosystems:

    1. Natural disasters (e.g., floods, wildfires)

    2. Human activities (e.g., deforestation)

    3. Invasive species introduction

1.6 - Adaptations

  • Explain the role of genetics in adaptations, influencing overall ecosystem health:

    • Terms to Include:

    • Adaptation: A trait that improves an organism's fitness.

    • Fitness: The ability of an organism to survive and reproduce.

    • Natural Selection: Process where organisms better adapted to their environment tend to survive and produce more offspring.

    • Selective Pressure: Any phenomena that alter the behavior and fitness of living organisms.

    • Evolution: The change in the heritable characteristics of biological populations over successive generations.

1.7 - Ecological Succession

  • Define ecological succession: The process by which the structure of a biological community evolves over time.

  • Explain the process of ecological succession:

    • Primary Succession: Occurs in lifeless areas (e.g. after volcanic eruptions), starting from bare rock.

    • Secondary Succession: Occurs in areas that were previously occupied but disturbed (e.g. after a fire), starting from existing soil and seeds.

Unit 3 - Populations

3.1 - Specialist vs Generalist Species


  • Comparison of characteristics:

    Characteristics

    Specialists

    Generalists


    Range of Tolerance

    Low

    High


    Prone to Extinction?

    More

    Less


    Adaptability

    Low

    High


    Example of Species

    Koala (specialized diet)

    Raccoon (omnivore)

    3.2 - K-Selected & r-selected Species


    • Comparison of characteristics:

      Characteristics

      K-selected

      r-selected


      Offspring

      Few

      Many


      Parental Care

      Lots

      Little


      Reproductive Events

      Few

      Many


      Lifespan

      Long

      Short


      Species Type

      Specialist

      Generalist


      Competition

      High

      Low


      Example of Species

      Elephants

      Cockroaches

      3.3 - Survivorship Curves

      • Survivorship curve: Graphs representing the number of individuals of a species that survive to a certain age.

      • Types of survivorship curves:

        • Type I: High survivorship until old age (e.g., humans).

        • Type II: Steady survivorship across ages (e.g., birds).

        • Type III: High mortality in early life stages (e.g., fish).

      3.4 - Carrying Capacity

      • Define carrying capacity: The maximum population size of a species that an environment can sustain.

      • Identify terms on a graph (not shown):

        • Carrying capacity

        • Overshoot

        • Die-off

      • Identify three limiting resources affecting carrying capacity:

        1. Space

        2. Food

        3. Water

      3.5 - Population Sampling

      • Draw three types of population distributions:

        1. Clumped

        2. Uniform

        3. Random

      • Calculation of population density (example not provided).

      • Identify the equation for population change:
        ext{Population Change} = ext{Births} + ext{Immigrations} - ext{Deaths} - ext{Emigrations}

      • Example of elk population calculation:
        a. Births = 19, Deaths = 6, Immigration = 5, Emigration = 0:
        Population Change = 19 + 5 - 6 - 0 = 18
        b. Initial population = 52, New Population = 52 + 18 = 70.

      • Capture-mark-recapture equation to estimate population size: N = rac{(M imes C)}{R} Where:

        • $N$: Total population size

        • $M$: Number marked

        • $C$: Total captured in second sample

        • $R$: Number recaptured (marked in the second sample).

      • Population estimation example in Glacier National Park (not shown).

      3.6 - Age Structure Diagrams

      • Identify age structure diagrams:

        • Expanding rapidly

        • Expanding slowly

        • Stable

        • Declining

      3.7 - Total Fertility Rate (TFR)

      • Factors influencing TFR include:

        1. Economic status

        2. Access to education and health care.

      3.8 - Human Population Dynamics

      • Growth rate (r) equation:
        r = rac{(Births - Deaths)}{Total Population}

      • Given crude birth rate (CBR) of 32 and crude death rate (CDR) of 6, calculate growth rate:
        r = CBR - CDR = 32 - 6 = 26

      • Identify the doubling time equation (Rule of 70):
        ext{Doubling Time} = rac{70}{r}

      • Given a growth rate of 2.25%, calculate doubling time:
        DT = rac{70}{2.25} ext{ years}

      3.9 - Demographic Transition

      • Diagram for demographic transition, showing transition from high birth/high death rates to low birth/low death rates through various stages.

      Unit 4 - Earth Systems & Resources

      4.1 - Plate Tectonics

      • Identify five layers of the Earth from innermost to outermost:

        1. Inner Core

        2. Outer Core

        3. Mantle

        4. Asthenosphere

        5. Crust

      • Identify the layer that contains tectonic plates: The lithosphere (upper mantle and crust).

      • Three types of plate boundaries:

        • Divergent: Plates move apart.

        • Convergent: Plates move together.

        • Transform: Plates slide past each other.

      • Cause of tectonic plate movement: Convection currents in the mantle.

      4.2 - Soil Formation & Erosion

      • Four soil horizons:

        1. O horizon (organic layer)

        2. A horizon (topsoil)

        3. B horizon (subsoil)

        4. C horizon (parent material)

      4.3 - Soil Composition & Properties

      • Table showing properties of soil types:

        Soil Type

        Particle Size

        Porosity

        Permeability

        Water Holding Capacity


        Sand

        Large

        Low

        High

        Low


        Silt

        Medium

        Medium

        Medium

        Medium


        Clay

        Small

        High

        Low

        High

        • Identify soil texture based on chart (not shown).

        • Identify three abiotic factors that can be tested in soil:

        1. pH

        2. Moisture content

        3. Nutrient levels

      4.4 - Atmosphere

      • Identify five layers of the atmosphere from closest to furthest from Earth:

        1. Troposphere

        2. Stratosphere

        3. Mesosphere

        4. Thermosphere

        5. Exosphere

      • Identify the layer where weather occurs: Troposphere.

      • Description of how atmospheric layers are defined:

        • Layers classified based on temperature variation.

      4.5 - Global Wind Patterns

      • Draw global wind patterns including atmospheric circulation patterns (cells): Hadley, Ferrel, and Polar cells.

      • Identify three properties of air:

        1. Density

        2. Temperature

        3. Humidity

      4.6 - Watersheds

      • Define a watershed: The land area that drains into a particular river, lake, or other body of water.

      • Describe three factors that impact watershed recharge:

        1. Land use changes (urbanization)

        2. Soil type (permeability)

        3. Vegetation cover.

      4.7 - Seasons

      • Diagram showing how Earth’s seasons work (not shown): including the sun, seasons, equator, Tropics of Cancer and Capricorn, and Earth’s axis tilt.

      • Describe equinox and solstice:

        • Equinox: Days when day and night are equal in length.

        • Solstice: Days with the longest or shortest daylight hours.

      4.8 - Earth’s Geography & Climate

      • How mountains affect local climates: Mountains can block precipitation, creating rain shadows.

      4.9 - El Nino and La Nina

      • Draw and describe oceanic conditions during a normal year, El Nino, and La Nina:

        • Normal Year: Warm water in western Pacific.

        • El Nino: Warmer waters shift toward the east, affecting weather patterns.

        • La Nina: Cooler waters in the eastern Pacific, leading to opposite weather effects.

      Unit 5 - Land & Water Use

      5.1 Tragedy of the Commons

      • Define the tragedy of the commons: A situation where shared resources are overused and depleted, leading to a shortage.

      • Examples in an environmental context:

        1. Overfishing

        2. Deforestation

        3. Overgrazing on commons.

      • Solutions to environmental tragedy of the commons:

        1. Regulation and enforcement

        2. Community management of resources

        3. Privatization of resources.

      5.2 Clearcutting

      • Describe three direct negative effects of clearcutting:

        1. Loss of habitat and biodiversity.

        2. Soil erosion.

        3. Water quality degradation.

      • Describe three direct positive effects of clearcutting:

        1. Increased sunlight penetration

        2. Economic gain for timber industry

        3. Potential for new growth in a controlled way.

      • Consequences of deforestation in terms of ecosystem services: Loss of carbon sequestration, water regulation, and habitat services ultimately destabilizes ecosystems.

      5.3 Green Revolution

      • Define Green Revolution: A period of agricultural transformation that increased food production through high-yield seeds, fertilizers, pesticides, and irrigation.

      • Six key developments of the Green Revolution:

        1. High-yield crops

        2. Chemical fertilizers

        3. Pesticides

        4. Irrigation techniques

        5. Mechanized farming

        6. Improved storage and transportation.

      • Positive and negative effects for each development:

        1. High-yield crops: Increased food production (Positive), reduced genetic diversity (Negative).

        2. Chemical fertilizers: Enhanced growth (Positive), soil depletion (Negative).

        3. Pesticides: Pest control (Positive), ecological harm (Negative).

        4. Irrigation techniques: Increased efficiency (Positive), water scarcity (Negative).

        5. Mechanization: Labor reduction (Positive), unemployment spikes (Negative).

        6. Improved storage: Reduced loss (Positive), increased energy costs (Negative).

      5.4 Impacts of Agricultural Practices

      • Four major agricultural practices in modern-day:

        1. Monoculture

        2. Agroforestry

        3. Organic farming

        4. Intensive farming.

      • Pros and cons of each practice:

        1. Monoculture: Pros: High efficiency; Cons: Soil degradation.

        2. Agroforestry: Pros: Biodiversity enhancement; Cons: Complexity in management.

        3. Organic farming: Pros: Health benefits; Cons: Lower yields.

        4. Intensive farming: Pros: Increased production; Cons: Environmental degradation.

      5.5 Irrigation

      • Identify and describe four main types of irrigation:

        1. Surface irrigation

        2. Drip irrigation

        3. Sprinkler systems

        4. Subsurface irrigation.

      • Identify three main problems due to irrigation:

        1. Waterlogging

        2. Salinization

        3. Aquifer depletion.

      • Define an aquifer: Underground layer of water-bearing rock.

      • Describe depletion of an aquifer: Over-extraction leads to reduced water availability and increased costs.

      5.6 Pest Control Methods

      • Define a pest: Any organism deemed undesirable due to its adverse effects on crops, humans or livestock.

      • Define a pesticide: A chemical substance used to kill pests, including weeds.

      • Four main types of pesticides and what they target:

        1. Insecticides - Target insects.

        2. Herbicides - Target weeds.

        3. Fungicides - Target fungi.

        4. Rodenticides - Target rodents.

      • Three pros and cons of pesticide use:

        • Pros: Increased yields, cost-effective, quick action.

        • Cons: Environmental toxicity, development of resistant pest species, harm to non-target organisms.

      5.7 Meat Production Methods

      • Two main forms of livestock raising:

        1. Pastured/Rangeland – Pros: Natural diet, better animal welfare; Cons: Requires more land, increased land degradation.

        2. Feedlot – Pros: Efficient and higher productivity; Cons: Pollution, ethical concerns regarding animal treatment.

      • Explanation of inefficiency of meat compared to other protein sources: Meat production requires significant resources (land, water), resulting in higher greenhouse gas emissions compared to plant proteins like soy, beans, peas, and nuts.

      5.8 Impacts of Overfishing

      • Define a fishery: A designated area for catching fish or fish populations harvested for consumption.

      • Explain why a fishery collapses: Overexploitation exceeds reproductive rates, resulting in diminished fish stocks.

      • Explain why recovery from a collapsed fishery is difficult: Disruption of breeding cycles and loss of biodiversity create barriers to replenishing fish populations.

      5.9 Mining

      • Match the term with the definition:

        • Metals: Elements that conduct electricity and heat, useful for building.

        • Ore: Raw, concentrated mineral containing the desired material.

        • Overburden: Soil, vegetation, and rocks removed prior to mining.

        • Reserve: Known amount of resource available for mining.

        • Tailings & Slag: Leftover waste material after mineral extraction.

      • Identify types of mines:

        1. Surface mines: Pros: Less expensive, easier access; Cons: Environmental degradation.

        2. Underground mines: Pros: More resource-efficient; Cons: Dangerous working conditions.

      5.10 Urbanization

      • Define urbanization: The population shift from rural to urban areas, often leading to city growth.

      • Examples of how urbanization increases overall CO2 emissions:

        1. Increased transportation emissions.

        2. Energy consumption in buildings.

        3. Land use changes increasing heat retention.

      • Describe current population trends regarding urbanization: More individuals moving to cities, leading to growing urban areas and related challenges.

      5.11 Ecological Footprint

      • Define ecological footprint: A measure of human demand on Earth’s ecosystems, representing the amount of natural capital used.

      • Differences between ecological footprint, carbon footprint, and water footprint:

        • Ecological footprint: Total environmental impact.

        • Carbon footprint: Impact related to greenhouse gas emissions.

        • Water footprint: Total volume of freshwater used.

      • Factors that increase ecological footprint:

        1. High consumption lifestyle.

        2. Non-sustainable farming practices.

      • Factors that decrease ecological footprint:

        1. Reduced consumption of resources.

        2. Shift to renewable energy sources.

      5.12 - Sustainability

      • Define sustainability: Meeting the needs of the present without compromising future generations' ability to meet their own needs.

      5.13 - Reducing Urban Runoff

      • Identify three common pollutants found in runoff:

        1. Nutrients (e.g., fertilizers)

        2. Heavy metals

        3. Sediments.

      • Describe four main ideas for reducing urban runoff:

        1. Green infrastructure (e.g., rain gardens).

        2. Permeable pavement.

        3. Improved drainage systems.

        4. Retention basins.

      5.14 - Integrated Pest Management (IPM)

      • Describe three approaches to pest management without pesticides or GMOs:

        1. Biological Control: Use of natural predators to control pests.

        2. Cultural Control: Adjusting farming practices to minimize pest establishment.

        3. Mechanical Control: Using barriers or traps to exclude or remove pests.

      5.15 - Sustainable Agriculture

      • Identify at least two key components of soil that sustainable agriculture aims to protect/conserve:

        1. Soil structure

        2. Nutrient content.

      • Describe three methods of sustainable agriculture:

        1. Crop rotation

        2. Organic fertilizers

        3. Conservation tillage.

      • Describe three natural methods for improving soil fertility:

        1. Cover cropping

        2. Green manures

        3. Composting.

      5.16 - Aquaculture

      • Describe pros and cons of aquaculture:

        • Pros: Reduces overfishing pressure, efficient food production.

        • Cons: Pollution, spread of diseases, habitat degradation.

      5.17 - Sustainable Forestry

      • Explain how selective or strip cutting is more sustainable than clearcutting: These methods maintain forest structure, reduce soil erosion, and preserve habitats.

      • Describe a prescribed burn: A controlled fire used to manage forest health, reduce underbrush, and prevent larger wildfires.