ecosystems

Ecosystem

____ is a Network Of

Interactions Among All Abiotic

Factors And Biotic Factors In A

Habitat”

It Consists Of All The Species In A

Community And Their Interactions With -

•Each Other

•Chemicals In The Environment

•Energy In The Environment

•Physical Aspects Of The Environment

The Properties Of Ecosystems Are Consistent With All Known Physical Laws Which are -

 Energy Cannot Be Created Nor Destroyed Only Transferred Or Transformed Into Another Form

• Ecosystems Require An External Energy Source That Fuels Carbohydrate Synthesis

 Some Energy Is Always Lost As Heat Or Light In Any Energy Conversion Process

• Energy Is Lost When Transferred Between Trophic Levels Due To Feeding

• Only Part Of The Energy Content Of Food Is Converted To New Cells And Tissues

 Matter Cannot Be Created Or Destroyed

• Ecosystems Require Chemical Input In The Form Of Elements And Molecules From External Sources

• Ecosystems Must Recycle Chemicals

Primary producers

____ ____ Provide Food Energy

(Carbohydrates)

Photosynthetic Species Use The Energy In Sunlight To

Convert Carbon Dioxide (CO2) To Carbohydrates That -

•Are Molecular Building Blocks Called Carbon Skeletons Or

Substrates

•Energize ATP Synthesis

•Photosynthetic Active Radiation (PAR) Is The Type Of

Sunlight That Energizes Photosynthesis

Photosynthetic active radiation (PAR)

The type of sunlight that energizes photosynthesis

Food energy

Primary Producers Provide Ecosystems With ____ ____

 Chemosynthetic Species Use The

Energy In Inorganic Chemicals

Like Fe, H2, H2S, Or NH3 To

Convert CO2 To Carbohydrates

• Chemosynthetic Prokaryote

Mutualists Are The Primary

Producers In The Hydrothermal

Vent Ecosystems

Chemosynthetic

Subterranean Ecosystems Are Energized By

____ Species and/or Plant Root Excretions

 Primary Producers Supply Some Underground Cave Ecosystems With The Carbohydrates That Support

These Ecosystems

Gross primary production (GPP)

____ ____ ____ Is The Amount Of Carbohydrates That Primary Producers Generate Per Unit Time In A Specific Habitat

 GPP Is A Function Of -

• Nutrient Availability

• Sunlight Availability

• Water Availability

Net primary production (NPP)

____ ____ ____ Is The Amount Of Food Energy In Autotroph Biomass Available To Heterotrophs

 NPP Is The Food Available To All The Consumers And Decomposers In An Ecosystem

• GPP Is Gross Pay

• NPP Is Net Pay After Taxes, etc

Sunlight, Temperature, Water, And Nutrient Availability

Gross Primary Production (GPP) In Ecosystems Is Primarily Determined By ____, ____, ____, ____, and ____ ____

Phosphorus (P) Drives Increased Algal Growth In Lake #226 In NW Ontario

• This Result Is The Basis For The Legislation That Regulates P Use In Canada

Whole Aquatic Ecosystem Experimentation In Canada In 1973 Concluded that -

Annual evapotranspiration (AET)

____ ____ Correlates With GPP And NPP

 AET Is The Total Amount Of Water That Evaporates And Is Transpired By Plants From A Landscape In One Year

[Millimeters (mm) Of Water/Year]

• AET Relates To Precipitation, T0, And Water Use By Plants

chemical building blocks

Primary Producers Input ____ ____ ____

Into The Living Components Of Ecosystems

They Obtain Elements And Molecules From Air, Soil,

And Water Including -

•Ca, Cl, Cu, Fe, I, K, Mg, Mn, N, Na, P, S

•CO2, H2O, H2S, NH3, NO2, NO3

This Enables All Species To -

• Activate Enzymes (Cofactors)

• Enable Muscle And Nervous System Function

• Make Antlers, Biological Molecules, Bone Tissue, Horns,

Shells, etc.

Inorganic chemicals

Some Consumers Directly Obtain ____ ____ From The Environment By Consuming

Mineral Licks, Salt Water, Soil, And Through Import By Gills

Nitrogen fixing species

____ ____ ____ Including The Cyanobacteria And Other Bacteria, Input Useful Nitrogen Molecules (NH3)

They “Fix Nitrogen” (N2 > NH3) To Produce

The NH3 Molecules That All Species Need

To Make -

• Amino Acids, Proteins

• Nucleotides, DNA, RNA

Cyanobacteria Are Keystone Species In

Some Aquatic Ecosystems

Nitrogen-Fixing Bacteria And Plant Mutualisms

Bradyrhizobia And Rhizobia Interact With Leguminous Plants Like Acacia Trees, Beans, Clover, And Peas To Form Root Nodules

•Nitrogen (N2) Is Converted To NH3 In Specialized Root Nodules

•Free-Living, Nitrogen-Fixing, Prokaryotes Also Input NH3

Decomposers

____ Recycle Chemicals

They Release Chemicals In Dead

Organic Matter Into Air, Soil, And

Water, Which Makes These Chemicals

Available To All Species

Fungi, Invertebrates, Prokaryotes,

Protozoa Are Decomposers

Detritovores Are Animals That Eat

Nonliving Organic Particles Including -

• Animal Particles

• Feces Particles

• Plant Particles

Scavengers

____ Are Vertebrate Decomposers

 Their Consumption Of Carcasses Recycles Chemicals In

Ecosystems (Nature’s Clean-Up Crew)

 Vulture Adaptations Include -

• Bald Heads, Lightweight Broad Winds For Soaring, And Strong

Hooked Beaks

• Keen Eyesight And Smell For Carillon Detection

• Strong Stomach Acid To Inactivates Harmful Items In Carrion

Consumers

The Activities Of ____ In Ecosystems Drive

Coevolution, Increase Biodiversity, And Promote New

Species Formation, Which Is Called Speciation

Apex Predators Are Keystone Species

Consumers Add Fertility To Aquatic Habitats And Soils Through Their

Carcasses And Excretions

Some Consumers Create Habitat

Some Primary Consumers -

•Are Pollinators And Seed Dispersers

•Drive Plant Speciation