Key ConceptsKey Concepts

Basic ecological principlesBasic ecological principles

Major components of ecosystemsMajor components of ecosystems

Matter cycles and energy flowMatter cycles and energy flow

Ecosystem studiesEcosystem studies

Ecological servicesEcological services

The Nature of EcologyThe Nature of Ecology

Ecosystem organizationEcosystem organization

OrganismsOrganisms

PopulationsPopulations

CommunitiesCommunities

EcosystemsEcosystems

BiosphereBiosphere Fig. 4-2 p. 66Fig. 4-2 p. 66

EcologyEcologyA. Ecology: study of interactions among organisms and their abiotic environments

1) organism: any form of life2) species: group of organisms with similar appearance (?) and ability to reproduce among themselves

a) estimated 5 to 100 million species (1.75 million known)3) population: group of individuals of a certain species in a given area4) habitat: where a population lives5) community: all populations in a given area6) ecosystem: all species and abiotic environment and their interactions7) biosphere: all ecosystems on earth8) ecotone: transition between ecosystems

a) edge effect:: an ecotone often has more biodiversity and higher population density

9) climate: long term weather10) biomes: all ecosystems of a certain type

The Earth’s Life-Support SystemsThe Earth’s Life-Support Systems

TroposphereTroposphere

StratosphereStratosphere

HydrosphereHydrosphere

LithosphereLithosphere

BiosphereBiosphereFig. 4-6 p. 68Fig. 4-6 p. 68

Sustaining Life of EarthSustaining Life of Earth

One-way flowof energy

One-way flowof energy

Cycling ofmatter

Cycling ofmatter

Fig. 4-7 p. 69Fig. 4-7 p. 69

The Source of EnergyThe Source of Energy

Fig. 4-8 p. 69Fig. 4-8 p. 69

The Sun

1) fusion (H = 72%; He = 28%)2) 93,000,000 miles, 8 minutes3) 4.2 million tons converted to energy every second4) of all incoming solar radiation (100%),

- 34% is reflected back by clouds, dust, oceans, land- 66% heats air, land, evaporates water- .023% is used in photosynthesis

5) most of the 72% leaves earth as IR (heat) - process of heat loss is slowed by natural greenhouse effect (H2O, CO2, CH4 etc)- without natural geenhouse effect life could not exist on earth

6) Geenhouse effect*If bond vibrational frequency is “in phase” with IR , bond absorbs energy, speeds up vibration and releases energy in all directions, some of which go back to surface.

Ecosystem Concepts and ComponentsEcosystem Concepts and Components

Biomes Biomes

Fig. 4-9 p. 70Fig. 4-9 p. 70

Role of climate

Role of climate

Aquatic life zones

Aquatic life zones

Ecosystem Boundaries: EcotonesEcosystem Boundaries: Ecotones

Fig. 4-10 p. 71Fig. 4-10 p. 71

Principles of Ecological FactorsPrinciples of Ecological Factors

Abiotic factorsAbiotic factorsBiotic factorsBiotic factors

Law of toleranceLaw of toleranceLimiting factorsLimiting factors

Fig. 4-14 p. 73; Refer to Fig. 4-13 p. 73Fig. 4-14 p. 73; Refer to Fig. 4-13 p. 73

Tolerance LimitsTolerance Limitsrange of tolerance

a) tolerance limits dam

b) organisms may acclimate to changing conditions but once they cross over the threshold (tolerance limit), they may suddenly diec) limiting factor: one factor that is more important than others in limiting population

coldlittle sunlightcold

The Biotic Components of EcosystemsThe Biotic Components of Ecosystems

Producers(autotrophs)

Producers(autotrophs)

Photosynthesis Photosynthesis

Consumers(heterotrophs)

Consumers(heterotrophs)

Aerobicrespiration

Aerobicrespiration

Decomposers Decomposers Fig. 4-16 p. 75Fig. 4-16 p. 75

Trophic LevelsTrophic Levels

Primary consumer (herbivore)Primary consumer (herbivore)

Secondary consumer (carnivore)Secondary consumer (carnivore)

Tertiary consumerTertiary consumer

OmnivoreOmnivore

Detritivores and scavengersDetritivores and scavengers

DecomposersDecomposers

BiodiversityBiodiversity

Genetic diversityGenetic diversity

Species diversitySpecies diversity

Ecological diversityEcological diversity

Functional diversityFunctional diversity

Connections: Food Webs and Energy Flow in EcosystemsConnections: Food Webs and Energy Flow in Ecosystems

Fig. 4-18 p. 77; Refer to Fig. 4-19 p. 78Fig. 4-18 p. 77; Refer to Fig. 4-19 p. 78

Food chainsFood chains Food websFood webs

Ecological PyramidsEcological Pyramids

Pyramid ofenergy flow

Pyramid ofenergy flow

Ecologicalefficiency

Ecologicalefficiency

Pyramid ofbiomass

Pyramid ofbiomass

Pyramid ofnumbers

Pyramid ofnumbers

Fig. 4-20 p. 79

Primary Productivity of EcosystemsPrimary Productivity of Ecosystems

Gross primary productivity (GPP)Gross primary productivity (GPP)

Net primary productivity (NPP)Net primary productivity (NPP)

Fig. 4-25 p. 81

Connections: Matter Cycling in EcosystemsConnections: Matter Cycling in Ecosystems

Biogeochemical cyclesBiogeochemical cycles

Hydrologic cycle (H2O)Hydrologic cycle (H2O)

Atmospheric cycles (C, N)Atmospheric cycles (C, N)

Sedimentary cycles (P, S)Sedimentary cycles (P, S)

Hydrologic (Water) CycleHydrologic (Water) Cycle

Fig. 4-27 p. 83Fig. 4-27 p. 83

The Carbon Cycle (Terrestrial)The Carbon Cycle (Terrestrial)

Fig. 4-28 p. 84-85Fig. 4-28 p. 84-85

The Carbon Cycle (Aquatic)The Carbon Cycle (Aquatic)

Fig. 4-28 p. 84-85Fig. 4-28 p. 84-85

The Nitrogen CycleThe Nitrogen CycleFig. 4-29 p. 86Fig. 4-29 p. 86

The Phosphorus CycleThe Phosphorus Cycle

Fig. 4-30 p. 88Fig. 4-30 p. 88

The Sulfur CycleThe Sulfur Cycle

Fig. 4-31 p. 89Fig. 4-31 p. 89

How Do Ecologists Learn About Ecosystems?How Do Ecologists Learn About Ecosystems?

Field researchField research

Remote sensingRemote sensing

Geographic information systems (GIS)Geographic information systems (GIS)

Laboratory researchLaboratory research

Systems analysisSystems analysis

GIS and Systems AnalysisGIS and Systems Analysis

Fig. 4-33 p. 91Fig. 4-33 p. 91Fig. 4-32 p. 91Fig. 4-32 p. 91

Ecosystem Servicesand SustainabilityEcosystem Servicesand Sustainability

Fig. 4-34 p. 92Fig. 4-34 p. 92