Chapter 4-1 & 4-2Chapter 4-1 & 4-2

Ecosystems: Ecosystems: What Are They and What Are They and How Do They Work?How Do They Work?

What would be an example of a parasite?

a. Ticks feeding on a deer

b. Startlings displacing bluebirds from nesting sites

c. Bees consuming nectar and carrying pollen from one flower to another

d. Moss growing on a tree trunk

QUESTION OF THE DAY

THE NATURE OF ECOLOGYTHE NATURE OF ECOLOGY Ecology is a study Ecology is a study

of connections in of connections in nature.nature. How organisms How organisms

interact with one interact with one another another (biotic) (biotic) and and with their nonliving with their nonliving (abiotic) (abiotic) environment.environment.

Figure 3-2Figure 3-2

Organisms and SpeciesOrganisms and Species Organisms, the different forms of life on Organisms, the different forms of life on

earth, can be classified into different species earth, can be classified into different species based on certain characteristics.based on certain characteristics.

Figure 3-3Figure 3-3

Members of a species interact in groups Members of a species interact in groups called called populationspopulations..

Populations of different species living and Populations of different species living and interacting in an area form a interacting in an area form a communitycommunity..

A community interacting with its physical A community interacting with its physical environment of matter and energy is an environment of matter and energy is an ecosystemecosystem..

Populations, Communities, and Ecosystems

PopulationsPopulations

A population is a A population is a group of interacting group of interacting individuals of the individuals of the same species same species occupying a specific occupying a specific area.area. The space an The space an

individual or individual or population normally population normally occupies is its habitat.occupies is its habitat.

Figure 3-4Figure 3-4

PopulationsPopulations

Genetic diversity Genetic diversity In most natural In most natural

populations populations individuals vary individuals vary slightly in their slightly in their genetic makeup.genetic makeup.

Figure 3-5Figure 3-5

Visualizing an EcosystemVisualizing an Ecosystem

biosphere

ecosystem

community

population

organism

THE EARTH’S LIFE SUPPORT THE EARTH’S LIFE SUPPORT SYSTEMSSYSTEMS

The biosphere The biosphere consists of several consists of several physical layers that physical layers that contain:contain: AirAir WaterWater SoilSoil Minerals Minerals LifeLife

Figure 3-6Figure 3-6

The Earth’s ComponentsThe Earth’s Components AtmosphereAtmosphere

Membrane of air around the planet.Membrane of air around the planet.

StratosphereStratosphere Lower portion contains ozone to filter out most of Lower portion contains ozone to filter out most of

the sun’s harmful UV radiation.the sun’s harmful UV radiation.

HydrosphereHydrosphere All the earth’s water: liquid, ice, water vaporAll the earth’s water: liquid, ice, water vapor

LithosphereLithosphere The earth’s crust and upper mantle.The earth’s crust and upper mantle.

The BiosphereThe Biosphere Biosphere: the space where organisms live and Biosphere: the space where organisms live and

interact. It includesinteract. It includes Most of the HydrosphereMost of the Hydrosphere Parts of the lower atmosphereParts of the lower atmosphere Parts of the upper lithosphereParts of the upper lithosphere

http://serc.carleton.edu/eslabs/climate/index.html

What Sustains Life on Earth?What Sustains Life on Earth?

1. Solar energy1. Solar energy

2. The cycling of 2. The cycling of mattermatter

3. Gravity 3. Gravity

sustain the earth’s sustain the earth’s life.life.

Figure 3-7Figure 3-7

The Effect of Solar Energy on the EarthThe Effect of Solar Energy on the Earth Solar energy flowing Solar energy flowing

through the biosphere through the biosphere

1. Warms the atmosphere1. Warms the atmosphere

2. Evaporates and 2. Evaporates and

recycles waterrecycles water

3. Generates winds and 3. Generates winds and

4. Supports plant growth.4. Supports plant growth.

Figure 3-8Figure 3-8

Ecosystem inputsEcosystem inputs

biosphere

constant inputof energyenergy flowsthrough

nutrients cycle

nutrients can only cycle

inputs energy nutrients

inputs energy nutrients

Don’t forgetthe laws of Physics!

Matter cannotbe created ordestroyed

consumers

decomposers

abioticreservoir

nutrientsmade availableto producers

geologicprocesses

Generalized Generalized Nutrient cyclingNutrient cycling

consumers

consumers

producers

decomposers

abioticreservoir

nutrientsENTER FOOD CHAIN= made availableto producers

geologicprocesses

Decompositionconnects all trophic levels

return toabioticreservoir

Summary Summary 1. What do ecologists study?

Interactions among organisms, populations, communities, ecosystems, and the biosphere.

2. How does a population differ from a community? Example

3. What is an ecosystem? A community of different species interacting with each other and with their nonliving environment of matter and energy. All of the earth’s diverse ecosystems comprise the biosphere.

4. What are the interconnected spherical layers make up the earth’s life-support system?

5. How does solar energy sustain life?

Chapter 4-3Chapter 4-3

Ecosystems ComponentsEcosystems Components

QUESTION OF THE DAY

All forms of water make up the

a. lithosphere

b.atmosphere

c. hydrosphere

d. tranosphere

e.biosphere

ECOSYSTEM COMPONENTSLife exists on land systems called • Biomes

Ex. deserts, forests, and grasslands

• Aquatic life zones in freshwater and ocean.

Ex. coral reefs, coastal estuaries, deep ocean

ECOSYSTEM COMPONENTSECOSYSTEM COMPONENTS

Figure 3-9Figure 3-9

Major biomes found along the 39th parallel across the United States

• What causes the differences?

Components of EcosystemsComponents of Ecosystems AbioticAbiotic: non-living living components: non-living living components

Ex. Ex.

BioticBiotic: living components.: living components.

Ex. Ex.

Figure 3-10Figure 3-10

Factors That Limit Population GrowthFactors That Limit Population Growth Availability of matter and energy resources Availability of matter and energy resources

can limit the number of organisms in a can limit the number of organisms in a population. Ex. population. Ex.

Figure 3-11Figure 3-11

Factors That Limit Population GrowthFactors That Limit Population Growth

The physical The physical conditions of the conditions of the environment can environment can limit the limit the distribution of a distribution of a species.species.

i.e. i.e.

Figure 3-12Figure 3-12

Major Biological ComponentsMajor Biological Components

Autotrophs (self-feeders): make their own food from compounds in the environment

Consumers (heterotrophs): feed on other organisms or their remains.

Natural ecosystems produce little waste or no waste. In nature, waste becomes food.

Producers: Basic Source of All FoodProducers: Basic Source of All Food

Most producers capture sunlight to produce Most producers capture sunlight to produce carbohydrates by carbohydrates by photosynthesisphotosynthesis::

Chemosynthesis:Some organisms such as deep ocean bacteria draw energy from hydrothermal vents and produce carbohydrates from hydrogen sulfide (H2S) gas .

Photosynthesis: Photosynthesis: A Closer LookA Closer Look

Chlorophyll molecules in the Chlorophyll molecules in the chloroplasts of plant cells chloroplasts of plant cells absorb solar energy.absorb solar energy.

This initiates a complex series This initiates a complex series of chemical reactions in which of chemical reactions in which carbon dioxide and water are carbon dioxide and water are converted to sugars and converted to sugars and oxygen.oxygen.

Figure 3-AFigure 3-A

ConsumersConsumers Consumers (heterotrophs) get their food by Consumers (heterotrophs) get their food by

eating or breaking down all or parts of other eating or breaking down all or parts of other organisms or their remains.organisms or their remains. HerbivoresHerbivores

• Primary consumers that eat producersPrimary consumers that eat producers

CarnivoresCarnivores• Secondary consumers eat primary consumersSecondary consumers eat primary consumers• Third and higher level consumers: carnivores that eat Third and higher level consumers: carnivores that eat

carnivores.carnivores.

OmnivoresOmnivores• Feed on both plant and animals.Feed on both plant and animals.

Role of Decomposers and Detritivores Detritivores: Insects or other scavengers that feed on wastes

or dead bodies.• They leave some parts and their feces that are converted to

energy by the decomposers.• Improve the nutritional value and the texture of the soil• Millipedes, earthworms and slugs feed on dead plants and

animals

Decomposers:• Recycle nutrients in ecosystems.• Help in the process of decay by converting what is left by the

detritivores • Bacteria and fungi

Figure 3-13

Decomposers and DetrivoresDecomposers and Detrivores

Figure 3-13Figure 3-13

Aerobic and Anaerobic Respiration: Getting Energy for Survival

Organisms break down carbohydrates and other organic compounds in their cells to obtain the energy they need

This is usually done through aerobic respiration. The opposite of photosynthesis

Aerobic and Anaerobic Respiration: Getting Energy for Survival

Anaerobic respiration or fermentation: Some decomposers get energy by breaking

down glucose (or other organic compounds) in the absence of oxygen.

The end products vary based on the chemical reaction:

• Methane gas• Ethyl alcohol• Acetic acid• Hydrogen sulfide

Two Secrets of Survival: Energy Flow and Matter Recycle

An ecosystem survives by a combination of

• Energy flow and• Matter recycling

Figure 3-14

BIODIVERSITYBIODIVERSITY

Figure 3-15Figure 3-15

Functional diversity: biological & chemical processes necessary for life

Genetic Diversity: variety of genetic material within a species or population

Species Diversity: the number of species present in different habitats.

Ecological Diversity: the variety of terrestrial & aquatic ecosystems in an area or on the earth.

BIODIVERSITYBIODIVERSITY

Figure 3-15Figure 3-15

Biodiversity Loss and Species Extinction: Remember HIPPO

H for habitat destruction and degradation

I for invasive species

P for pollution

P for human population growth

O for overexploitation

Why Should We Care About Biodiversity? Why Should We Care About Biodiversity?

Biodiversity provides us with:Biodiversity provides us with: Natural Resources (food water, wood, energy, Natural Resources (food water, wood, energy,

and medicines)and medicines)

Natural Services (air and water purification, soil Natural Services (air and water purification, soil fertility, waste disposal, pest control)fertility, waste disposal, pest control)

Aesthetic pleasureAesthetic pleasure

SolutionsSolutions

Goals, strategies and Goals, strategies and tactics for protecting tactics for protecting biodiversity.biodiversity.

• Species approachSpecies approach

• Ecosystem Approach Ecosystem Approach

Figure 3-16Figure 3-16

SUMMARYSUMMARY1. Why do limiting factors affect species’ range?

2. What are the two major biological components of ecosystems?

3. How are the roles of decomposers and detritivores related?

4. What are the four kinds of biodiversity?

5. What are the causes of biodiversity loss and species extinction?

Chapter 4-4 & 4-5Chapter 4-4 & 4-5

Energy Flow in EcosystemsEnergy Flow in Ecosystems& &

Primary ProductivityPrimary Productivity

Energy Flow

ENERGY FLOW IN ECOSYSTEMSENERGY FLOW IN ECOSYSTEMS

Food chains and webs show how eaters, the Food chains and webs show how eaters, the eaten, and the decomposed are connected to eaten, and the decomposed are connected to one another in an ecosystem.one another in an ecosystem.

Figure 3-17Figure 3-17

Food WebsFood Webs

Trophic levels are Trophic levels are interconnected interconnected within a more within a more complicated food complicated food web.web.

What is the purpose What is the purpose of a food web?of a food web?

Figure 3-18Figure 3-18

Energy Flow in an Ecosystem: Losing Energy Flow in an Ecosystem: Losing Energy in Food Chains and WebsEnergy in Food Chains and Webs

In accordance with the 2In accordance with the 2ndnd law of law of thermodynamics, there is a decrease in the thermodynamics, there is a decrease in the amount of energy available to each amount of energy available to each succeeding organism in a food chain or web.succeeding organism in a food chain or web.

Energy Flow in an Ecosystem: Losing Energy Flow in an Ecosystem: Losing Energy in Food Chains and WebsEnergy in Food Chains and Webs

Ecological efficiency: percentage of useable energy transferred as

biomass from one trophic level to the next.

• % energy transferred:

• Where does the majority of energy go?

• How does this effect the # of organisms found in each trophic level?

Figure 3-19Figure 3-19

Productivity of Producers: Productivity of Producers: The Rate Is CrucialThe Rate Is Crucial

Gross primary production (GPP) Rate at which an

ecosystem’s producers convert solar energy into chemical energy as biomass.

Which areas have the greatest GPP?

Figure 3-20Figure 3-20

Net Primary Production (NPP)Net Primary Production (NPP)

NPP = GPP – RNPP = GPP – R Rate at which Rate at which

producers use producers use photosynthesis to photosynthesis to store energy minus store energy minus the rate at which they the rate at which they use some of this use some of this energy through energy through respiration (R).respiration (R).

Figure 3-21Figure 3-21

What are nature’s three most productive and What are nature’s three most productive and three least productive systems?three least productive systems?

Figure 3-22Figure 3-22

Chapter 4-4 /4-5 Chapter 4-4 /4-5 SummarySummary1. Food Chains: 1. Food Chains:

2. Food Webs2. Food Webs

3. 13. 1stst Law of Thermodynamics Law of Thermodynamics

4. 24. 2ndnd Law of Thermodynamics Law of Thermodynamics

5. Efficiency of Energy Flow5. Efficiency of Energy Flow

6. Pyramid of Energy6. Pyramid of Energy

7. Pyramid of Biomass7. Pyramid of Biomass

8. Gross Primary Productivity8. Gross Primary Productivity

9. Net Primary Productivity 9. Net Primary Productivity

Chapter 4-7Chapter 4-7

Matter Cycling in EcosystemsMatter Cycling in Ecosystems

Matter & Energy Transfer

MATTER CYCLING IN MATTER CYCLING IN ECOSYSTEMSECOSYSTEMS

Nutrient Cycles: Global Recycling Global Cycles recycle nutrients through the

earth’s air, land, water, and living organisms.

Nutrients are the elements and compounds that organisms need to live, grow, and reproduce.

Biogeochemical cycles move these substances through air, water, soil, rock and living organisms.

Background on Biogeochemical cyclesBackground on Biogeochemical cycles Earth system has four parts

Atmosphere Hydrosphere Lithosphere Biosphere

Biogeochemical cycles: The chemical interactions (cycles) that exist between the atmosphere, hydrosphere, lithosphere, and biosphere.

Abiotic (physio-chemical) and biotic processes drive these cycles

Commonalities of the CyclesCommonalities of the Cycles Each nutrient typically exists in different parts of

the Earth System

There are ‘Pools’ or reservoirs Fluxes in and out of pools Chemical or biochemical transformations

Transformations (or processes) Help to move nutrients between parts of the earth’s

system Can lead to positive & negative consequences

Examples of Examples of Transformations/ProcessesTransformations/Processes

1. Carbon cycle: Organic compounds to CO2 (processes: respiration, decomposition, or fire)

2. Carbon cycle: CO2 to organic compounds (process: photosynthesis)

3. Nitrogen cycle: N2 to NO3 (atmospheric nitrogen to plant utilizable nitrate) (process: N-fixation)

4. Nitrogen cycle: N2 to NH3 (plant utilizable ammonia) (process: Haber-Bosch Industrial N-fixation)

5. Water cycle: Liquid water to water vapor (process: evaporation and transpiration)

6. Water cycle: Water vapor to liquid water (process: condensation)

The Water CycleThe Water Cycle

Figure 3-26Figure 3-26

Water’ Unique PropertiesWater’ Unique Properties

There are strong forces of attraction between molecules of water.

Water exists as a liquid over a wide temperature range.

Liquid water changes temperature slowly.

It takes a large amount of energy for water to evaporate.

Liquid water can dissolve a variety of compounds.

Water expands when it freezes.

Effects of Human Activities Effects of Human Activities on Water Cycleon Water Cycle

We alter the water cycle by: Withdrawing large amounts of freshwater.

Clearing vegetation and eroding soils.

Polluting surface and underground water.

Contributing to climate change.

The Carbon Cycle:The Carbon Cycle:Part of Nature’s ThermostatPart of Nature’s Thermostat

Figure 3-27Figure 3-27

5000

http://www.epa.gov/climatechange/kids/carbon_cycle_version2.html

Carbon Cycle

Effects of Human Activities Effects of Human Activities on Carbon Cycleon Carbon Cycle

We alter the We alter the carbon cycle by carbon cycle by adding excess COadding excess CO22 to the atmosphere to the atmosphere through:through: Burning fossil fuels.Burning fossil fuels.Ex. Ex.

Clearing vegetation Clearing vegetation faster than it is faster than it is replaced.replaced.

Figure 3-28Figure 3-28

The Nitrogen Cycle: The Nitrogen Cycle: Bacteria in ActionBacteria in Action

Figure 3-29Figure 3-29

Nitrogen CycleNitrogen Cycle

Forms of Nitrogen (NForms of Nitrogen (N22))

http://soil.gsfc.nasa.gov/NFTG/nitrocyc.htm

1. N2 - inert gas, 78% of the atmosphere

2. NO, N20, NO2 - other gases of nitrogen, not directly biologically important. Part of the gases found in smog.

3. NO3- (nitrate) and NH4

+ (ammonium) -- ionic forms of nitrogen that are biologically usable.

Forms & Sources of Biologically Available Forms & Sources of Biologically Available Nitrogen (NNitrogen (N22))

http://soil.gsfc.nasa.gov/NFTG/nitrocyc.htm

For Plants• NO3

- (nitrate) • NH4

+ (ammonium) •Sources: N-fixation by plants (N2 to NH3 and N2 to NO3), lightening, bacteria decomposition of organic N (amino acids & proteins)

For Animals•Organic forms: amino acids and proteins (from plants or other animals)

Losses of Nitrogen from systemLosses of Nitrogen from system

http://soil.gsfc.nasa.gov/NFTG/nitrocyc.htm

• In bogs, lakes (places of low oxygen), NO3- is converted to N2

by bacteria (get their oxygen from the NO3)

• Volatilization of NH4+ (urea) to ammonia gas (NH3) - warm, dry

conditions.

• Leaching of NO3- (nitrate)

• Erosion

• Fire (combustion)

Pneumonic DevicePneumonic Device

FIXFIX AA

NN NN

AA PP

AA AA

DD NN

Nitrogen Cycle: Key PointsNitrogen Cycle: Key Points Nitrogen is in the atmosphere as NNitrogen is in the atmosphere as N2 2 (78%)(78%)

NN22 is an inert gas and cannot be used by plants or animals is an inert gas and cannot be used by plants or animals

NN22 can be converted to a usable form via can be converted to a usable form via Lightening Lightening N-fixing plants and cyanobacteriaN-fixing plants and cyanobacteria Industrial process (energy intensive)Industrial process (energy intensive)

Nitrogen limits plant growthNitrogen limits plant growth

Nitrogen is easily lost from biological systemsNitrogen is easily lost from biological systems

Effects of Human Activities Effects of Human Activities on the Nitrogen Cycleon the Nitrogen Cycle

We alter the nitrogen cycle by:We alter the nitrogen cycle by: Adding gases that contribute to acid rain.Adding gases that contribute to acid rain.

Adding nitrous oxide to the atmosphere through farming Adding nitrous oxide to the atmosphere through farming practices which can warm the atmosphere and deplete practices which can warm the atmosphere and deplete ozone.ozone.

Contaminating ground water from nitrate ions in inorganic Contaminating ground water from nitrate ions in inorganic fertilizers.fertilizers.

Releasing nitrogen into the troposphere through Releasing nitrogen into the troposphere through deforestation.deforestation.

Effects of Human Activities Effects of Human Activities on the Nitrogen Cycleon the Nitrogen Cycle

Human activities Human activities such as such as production of production of fertilizers now fix fertilizers now fix more nitrogen more nitrogen than all natural than all natural sources sources combined.combined.

Figure 3-30Figure 3-30

The Phosphorous CycleThe Phosphorous Cycle

Figure 3-31Figure 3-31

Effects of Human Activities Effects of Human Activities on the Phosphorous Cycleon the Phosphorous Cycle

We remove large amounts of phosphate from We remove large amounts of phosphate from the earth to make fertilizer.the earth to make fertilizer.

We reduce phosphorous in tropical soils by We reduce phosphorous in tropical soils by clearing forests.clearing forests.

We add excess phosphates to aquatic We add excess phosphates to aquatic systems from runoff of animal wastes and systems from runoff of animal wastes and fertilizers.fertilizers.

The Sulfur CycleThe Sulfur Cycle

Figure 3-32Figure 3-32

Effects of Human Activities Effects of Human Activities on the Sulfur Cycleon the Sulfur Cycle

We add sulfur dioxide to the atmosphere by:We add sulfur dioxide to the atmosphere by: Burning coal and oilBurning coal and oil

Refining sulfur containing petroleum.Refining sulfur containing petroleum.

Convert sulfur-containing metallic ores into free Convert sulfur-containing metallic ores into free metals such as copper, lead, and zinc releasing metals such as copper, lead, and zinc releasing sulfur dioxide into the environment.sulfur dioxide into the environment.

Chapter 4-7 Chapter 4-7 SummarySummary1. Biogeochemical cycles nutrients through air, water, soil, rock and living organisms.

2. Human activities impact the cycle

3. Water (hydrologic) cycle

4. Carbon cycle

5. Nitrogen Cycle

6. Phosphorus Cycle

7. Sulfur Cycle

Chapter 4-6Chapter 4-6

SoilsSoils

SOIL: A RENEWABLE RESOURCESOIL: A RENEWABLE RESOURCE

Soil is a slowly renewed resource that Soil is a slowly renewed resource that provides most of the nutrients needed for provides most of the nutrients needed for plant growth and also helps purify water.plant growth and also helps purify water. Soil formation begins when bedrock is broken Soil formation begins when bedrock is broken

down by physical, chemical and biological down by physical, chemical and biological processes called processes called weatheringweathering..

Mature soilsMature soils, or soils that have developed , or soils that have developed over a long time are arranged in a series of over a long time are arranged in a series of horizontal layers called horizontal layers called soil horizonssoil horizons..

SOIL: A RENEWABLE RESOURCESOIL: A RENEWABLE RESOURCE

Figure 3-23Figure 3-23

Fig. 3-23, p. 68

Fern

Mature soil

Honey fungus

Root system

Oak tree

Bacteria

Lords and ladies

Fungus

Actinomycetes

Nematode

Pseudoscorpion

Mite

RegolithYoung soil

Immature soil

Bedrock

Rockfragments

Moss and lichen

Organic debrisbuilds upGrasses and

small shrubs

Mole

Dog violet

Woodsorrel

EarthwormMillipede

O horizonLeaf litter

A horizon

Topsoil

B horizonSubsoil

C horizon

Parent material

Springtail

Red Earth Mite

Layers in Mature SoilsLayers in Mature Soils

Infiltration: the downward movement of water Infiltration: the downward movement of water through soil.through soil.

Leaching: dissolving of minerals and organic Leaching: dissolving of minerals and organic matter in upper layers carrying them to lower matter in upper layers carrying them to lower layers.layers.

The soil type determines the degree of The soil type determines the degree of infiltration and leaching.infiltration and leaching.

Soil Profiles of the Soil Profiles of the Principal Terrestrial Principal Terrestrial

Soil Types Soil Types

Figure 3-24Figure 3-24

Fig. 3-24a, p. 69

Mosaic of closely packed pebbles, boulders

Weak humus-mineral mixture

Dry, brown to reddish-brown with variable accumulations of clay, calcium and carbonate, and soluble salts

Alkaline, dark, and rich in humus

Clay, calcium compounds

Desert Soil(hot, dry climate)

Grassland Soilsemiarid climate)

Fig. 3-24b, p. 69

Tropical Rain Forest Soil(humid, tropical climate)

Acidic light-colored humus

Iron and aluminum compounds mixed with clay

Fig. 3-24b, p. 69

Deciduous Forest Soil(humid, mild climate)

Forest litter leaf moldHumus-mineral mixtureLight, grayish-brown, silt loamDark brown firm clay

Fig. 3-24b, p. 69

Coniferous Forest Soil(humid, cold climate)

Light-colored and acidic

Acid litter and humus

Humus and iron and aluminum compounds

Some Soil PropertiesSome Soil Properties

Soils vary in the size Soils vary in the size of the particles they of the particles they contain, the amount contain, the amount of space between of space between these particles, and these particles, and how rapidly water how rapidly water flows through them.flows through them.

Figure 3-25Figure 3-25

Fig. 3-25, p. 70

0.05–2 mmdiameter

High permeability Low permeability

WaterWater

Clayless than 0.002 mm

Diameter

Silt0.002–0.05 mm

diameter

Sand

HOW DO ECOLOGISTS LEARN ABOUT HOW DO ECOLOGISTS LEARN ABOUT ECOSYSTEMS?ECOSYSTEMS?

Ecologist go into ecosystems to observe, but Ecologist go into ecosystems to observe, but also use remote sensors on aircraft and also use remote sensors on aircraft and satellites to collect data and analyze satellites to collect data and analyze geographic data in large databases.geographic data in large databases. Geographic Information SystemsGeographic Information Systems Remote SensingRemote Sensing

Ecologists also use controlled indoor and Ecologists also use controlled indoor and outdoor chambers to study ecosystemsoutdoor chambers to study ecosystems

Geographic Information Systems (GIS)Geographic Information Systems (GIS)

A GIS organizes, A GIS organizes, stores, and analyzes stores, and analyzes complex data complex data collected over broad collected over broad geographic areas.geographic areas.

Allows the Allows the simultaneous simultaneous overlay of many overlay of many layers of data.layers of data.

Figure 3-33Figure 3-33

Fig. 3-33, p. 79

Critical nesting sitelocations

USDA Forest ServiceUSDA

Forest ServicePrivateowner 1 Private owner 2

Topography

Habitat type

LakeWetlandForest

Grassland

Real world

Systems AnalysisSystems Analysis

Ecologists develop Ecologists develop mathematical and mathematical and other models to other models to simulate the simulate the behavior of behavior of ecosystems.ecosystems.

Figure 3-34Figure 3-34

Fig. 3-34, p. 80

SystemsMeasurement

Define objectivesIdentify and inventory variablesObtain baseline data on variables

Make statistical analysis of relationships among variables

Determine significant interactions

Objectives Construct mathematical model describing interactions among variables

Run the model on a computer, with values entered for differentVariables

Evaluate best ways to achieve objectives

DataAnalysis

SystemModeling

SystemSimulation

SystemOptimization

Importance of Baseline Importance of Baseline Ecological DataEcological Data

We need baseline data on the world’s We need baseline data on the world’s ecosystems so we can see how they are ecosystems so we can see how they are changing and develop effective strategies for changing and develop effective strategies for preventing or slowing their degradation.preventing or slowing their degradation. Scientists have less than half of the basic Scientists have less than half of the basic

ecological data needed to evaluate the status of ecological data needed to evaluate the status of ecosystems in the United Sates (Heinz ecosystems in the United Sates (Heinz Foundation 2002; Millennium Assessment 2005).Foundation 2002; Millennium Assessment 2005).