Ecosystems: What Are They and How Do They Work? G. Tyler Miller’s Living in the Environment 14 th Edition Chapter 4 G. Tyler Miller’s Living in the Environment 14 th Edition Chapter 4

Key Concepts  Basic ecological principles  Major components of ecosystems  Matter cycles and energy flow  Ecosystem studies  Principles of Sustainability

The Nature of Ecology  Ecosystem organization  Organisms  Populations  Communities  Ecosystems  Biosphere Fig. 4-2 p. 57

The Earth’s Life-Support Systems  Troposphere  Stratosphere  Hydrosphere  Lithosphere  Biosphere Fig. 4-7 p. 60

Natural Capital: Sustaining Life of Earth  One-way flow of energy from Sun  Cycling of Crucial Elements  Gravity Fig. 4-8 p.60

Solar Capital: Flow of Energy to and from the Earth Fig. 4-9 p. 61

Natural Capital: Major Biomes  Biomes Fig p. 62  Role of climate  Aquatic life zones

Ecosystem Factors  Abiotic factors  Biotic factors  Range of tolerance  Limiting factors Fig p. 64

Components of Ecosystems  Producers (autotrophs)  Photosynthesis  Consumers (heterotrophs)  Aerobic respiration  Decomposers Fig p. 67  Abiotic chemicals

Biodiversity  Genetic diversity  Species diversity  Ecological diversity  Functional diversity

Connections: Energy Flow in Ecosystems  Trophic Levels  Food webs  Food chains

Trophic Levels  Primary consumer (herbivore)  Secondary consumer (carnivore)  Tertiary consumer  Omnivore  Detritivores and scavengers  Decomposers

Connections: Food Chains and Energy Flow in Ecosystems Fig p. 68

Ecological Pyramids  Pyramid of energy flow  Ecological efficiency  Pyramid of biomass  Pyramid of numbers Fig p. 70

Primary Productivity of Ecosystems  Gross primary productivity (GPP)  Net primary productivity (NPP) Fig p. 72

Soils  Origins  Importance  Maturity and Horizons  Variations with Climate and Biomes  Variations in Texture and Porosity  Origins  Importance  Maturity and Horizons  Variations with Climate and Biomes  Variations in Texture and Porosity

Soil Profiles in Different Biomes Fig. 4-27, p. 75

Connections: Matter Cycling in Ecosystems  Biogeochemical cycles  Hydrologic cycle (H 2 O)  Carbon cycle  Phosphorus cycle  Nitrogen cycle  Sulfur cycle

Hydrologic (Water) Cycle Fig p. 76

The Carbon Cycle (Marine) Fig. 4-29, p. 78

The Carbon Cycle (Terrestrial) Fig. 4-29, p. 78

The Nitrogen Cycle Fig p. 80

The Phosphorus Cycle Fig p. 82

The Sulfur Cycle Fig p. 83

How Do Ecologists Learn About Ecosystems?  Field research  Remote sensing  Geographic information systems (GIS)  Laboratory research  Systems analysis

Geographic Information System (GIS) Fig p. 84

Systems Analysis Fig p. 85