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

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

Section 1: The Nature of Ecology What is ecology? What species rule the world? What is population and levels of organization of matter in nature? What are communities and ecosystems?

What is ecology? Ecology: is the study of how organisms interact with another and the nonliving world. Connections in nature Organism: any form of life Cell: basic unit of life Eukaryotic: nucleus/organelles Prokaryotic: bacteria/algae Ecology: is the study of how organisms interact with another and the nonliving world. Connections in nature Organism: any form of life Cell: basic unit of life Eukaryotic: nucleus/organelles Prokaryotic: bacteria/algae

What is ecology? Species: groups of organisms that resemble each other in appearance, behavior, chemistry and genetic makeup…able to reproduce 3.6 to 100 million species (1.4 identified) Mostly insects/micro Tropical forests

Insects 751,000 Protists 57,700 Plants 248,400 Prokaryotes 4,800 Fungi 69,000 Other animals 281,000 Known species 1,412,000

What species rule the world? What types of organisms do you think your body contains billions of? Hint: they can be both very important to your survival or make you ill.

What species rule the world? Microbes (bacteria, protozoa, fungus, yeast) rule the world. Malaria Germs Good versus bad microbes Help keep us alive Microbes (bacteria, protozoa, fungus, yeast) rule the world. Malaria Germs Good versus bad microbes Help keep us alive

What are levels of organization in nature Ecology focuses on 5 levels of organization in nature: 1)Organisms 2)Populations 3)Communities 4)Ecosystems 5)Biosphere

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

Section 2: The Earth’s Life Support Systems What are the major parts of earth’s life- supporting systems? How does the sun sustain life of earth?

Earth’s Life Supporting Systems The Earth is made up of interconnected spherical layers that contain: Air Water Soil Minerals Life All parts are interconnected and the goal is to understand how they all interact.

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

Natural Capital: Sustaining Life of Earth Solar energy, the cycling of matter and nutrients, and gravity all sustain life on earth as we know it. KEY IDEA: remember energy and matter can not be created or destroyed. Solar energy, the cycling of matter and nutrients, and gravity all sustain life on earth as we know it. KEY IDEA: remember energy and matter can not be created or destroyed.

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 Gigantic nuclear fusion 93 million miles away sustains life. One-billionth of sun’s energy reaches earth. Energy in MUST equal energy out…WHY?

Section 3: Ecosystem Components What are the major components of ecosystems? What are tolerance limits? What factors limit population growth? What are producers, consumers, decomposers and what role do they play in ecosystems? What is biodiversity?

Life on Land and Sea Biomes: land portions of the biosphere… Forests, deserts, grasslands, tundra classified by climate and species adapted to it. Aquatic Life Zones: watery parts of biosphere… Fresh water (lakes, streams, etc.) Marine Life Zones (coral reefs, deep ocean, etc.)

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 Availability of matter and energy resources can limit organisms population.

Ecosystem Factors Limiting Factor Principle: too much or too little of any abiotic factor can limit or prevent growth of a population, even if all other factors are near or above optimum. Why are there no citrus fruit growing in NJ? Why do trees grow toward the sky?

Major Biomes found across the US at 39 0 North Latitude.

Major components of a freshwater ecosystem

Major components of a field ecosystem What are the biotic and abiotic factors? What might some limiting factors be?

Major components of a marine ecosystem Limiting factors may include: Salinity Ph Sunlight Dissolved oxygen Temperature

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

Photosynthesis: Producers CO 2 + H 2 O + Solar Energy >>> Glucose + Oxygen 6CO H 2 O + Solar Energy >>> C 6 H 12 O 6 + 6O 2

Detritus Feeders (Detritivores) no waste in natural ecosystems

Aerobic Respiration Glucose + Oxygen >>> Carbon Dioxide + Water + Energy C 6 H 12 O 6 + 6O 2 >>> 6CO 2 + 6H 2 O + energy

What is Biodiversity?  Genetic diversity  Species diversity  Ecological diversity Many scientists feel the loss of biodiversity is the greatest threat humans face.

Importance of Biodiversity d/bioImport.htmhttp:// d/bioImport.htm

Extinctions… Extinction occurs when there are no longer any living individuals of a species left. There have been five periods of mass extinction's on earth 440m, 370m, 250m, 210m and 65m years ago. Scientists estimate that currently, living organisms represent only 1% of all the species that have ever been (i.e. 99% have been and gone)

Energy Flow in Ecosystems There is a decrease in the amount of energy available to each succeeding organisms in a food chain or web. What does that mean? Where does the energy go?

Connections: Energy Flow in Ecosystems  Trophic Levels : producer to primary consumer to secondary consumer and so on…  Trophic Levels : producer to primary consumer to secondary consumer and so on…  Food webs : real ecosystems are more complex as most consumers feed on more than one organism.  Food webs : real ecosystems are more complex as most consumers feed on more than one organism.  Food chains : the sequence of organisms food sources  Food chains : the sequence of organisms food sources

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 90% energy loss each step! Ranges from 60 to 98% (90% is typical)

Primary Productivity of Ecosystems Estimated productivity per unit area of major ecosystems

Earth’s productivity: On land forests are highly productive in dark green, deserts least in brown. At sea, red indicates high productivity and deep oceans dark blue.

Productivity of Ecosystems The number of consumer organisms the earth can support is determined by how fast producers can supply them with energy. Planet’s limiting factor

Productivity of Ecosystems Humans are using, wasting and destroying the world’s biomass faster than producers are able to make it. Habitat destruction Humans are using, wasting and destroying the world’s biomass faster than producers are able to make it. Habitat destruction Clear Cut Forest in OR

Section 6: Soils Key Idea  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

What is Soil and Why Is It Important? Soil is a thin layer over most land that is a complex mix of rock, nutrients, decaying matter, water, air and billions of organisms…many microscopic decomposers.

What is Soil and Why Is It Important? Renewable resource…SLOW Depends upon climate (1cm in 15yrs.) Basis of life Filters water Water storage Habitat Renewable resource…SLOW Depends upon climate (1cm in 15yrs.) Basis of life Filters water Water storage Habitat

Soil Profiles Mature Soil have a long time to form and are arranged into layers called horizons.

Simplified food web found in soils

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

Soil particles come in different textures…sand, clay, silt gravel

Section 7: Matter Cycling in Ecosystems  Biogeochemical cycles  Group 1: Hydrologic cycle (H 2 O)  Group 2: Carbon cycle  Group 4: Phosphorus cycle  Group 3: Nitrogen cycle  Group 5: Sulfur cycle

Hydrologic (Water) Cycle: Group 1 Fig p. 76

The Carbon Cycle (Marine): Group 2 Fig. 4-29, p. 78

The Carbon Cycle (Terrestrial): Group 2 Fig. 4-29, p. 78

The Nitrogen Cycle: Group 3 Fig p. 80

The Phosphorus Cycle: Group 4 Fig p. 82

The Sulfur Cycle: Group 5 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