Ecosystems What Are They and How Do They

Ecosystems: What Are They and How Do They Work? Part 1 Intro to Ecology

Cell Theory 1. All living things are composed of cells. 2. Cells are the basic units of structure and function in living things. 3. All cells are produced from other cells.

Prokaryotes and Eukaryotes Pro Karyote Eu Karyote Before the nucleus After the nucleus

Structure of a Eukaryotic Call and a Prokaryotic Cell

Your Turn! § Atoms to Universe

Ecologists Study Connections in Nature § Ecology - study of how organisms interact with one another and with their physical environment of matter and energy.

Levels of Organization of Life § Organism- a living thing § Population- a group of organisms of the same species that live in a particular area § Community- populations of different species that live in one particular area

Levels of Organization of Life Ecosystem- all of the biotic and abiotic factors in one particular area § • Biotic- living things • • Ex: seaweed, fish, etc. Abiotic- non-living things • Ex: water temperature, p. H, salinity

Major Biotic and Abiotic Components of an Ecosystem

How many different organisms are there on Earth?

Almost 2 million! • Tremendous diversity • Scientists estimate between 10 and 14 million species yet to be discovered

Most are Bugs! Have You Thanked the Insects Today? § Pollinators § Population Control § Loosen and renew soil § Reproduce rapidly § Very resistant to extinction

Habitat vs. Niche § Habitat – place where an organism lives • Organisms address § Niche – role of an organism in an ecosystem (physical, chemical, and biological conditions that a species needs to live and reproduce) • Organisms occupation § Thousands of organisms can occupy the same habitat but each organism has its own niche.

Habitat vs. Niche

Niche Video Clip

Core Case Study: Tropical Rain Forests Are Disappearing § Cover about 2% of the earth’s land surface § Contain about 50% of the world’s known plant and animal species § Disruption will have three major harmful effects 1. Reduce biodiversity 2. Accelerate global warming 3. Change regional weather patterns

Natural Capital Degradation: Satellite Image of the Loss of Tropical Rain Forest Santa Cruz, Bolivia

Planet Earth Video Clip § Jungles • 00: 00 – 18: 00 § Fill out Atoms Universe Worksheet as you watch! • 5 examples of habitat vs. niche

Ecosystems: What Are They and How Do They Work? Part 2 Life Support Systems

The Earth’s Life-Support System Has Four Major Components § Hydrosphere – all the water on or near the Earth’s surface • Liquid water • Ice • Water vapor § Geosphere – Earth’s interior; contains nonrenewable fossil fuels • Core • Mantle • Outer Crust

Natural Capital: General Structure of the Earth § Biosphere – parts of atmosphere, biosphere, hydrosphere, and geosphere occupied by life • 6 miles above Earth’s surface to the bottom of the ocean

If the world were an apple… § The biosphere would be no thicker than the apple’s skin!

The Earth’s Life-Support System Has Four Major Components § Atmosphere – gasses surrounding the Earth’s surface • Troposphere – inner layer; 11 miles • Air we breathe: • 78% Nitrogen • 21% Oxygen • 1% water vapor, carbon dioxide, and methane

The Earth’s Life-Support System Has Four Major Components § Atmosphere – gasses surrounding the Earth’s surface • Stratosphere – outer layer; 11 -31 miles • Contains ozone layer to filter sun’s harmful rays

What Happens to Solar Energy Reaching the Earth? § Radiation – UV, visible light, and IR energy • 95% Absorbed by ozone • 1% Absorbed by the earth • Reflected by the earth as longer IR wavelengths • Hit greenhouse gases, vibrate, and release longer wavelengths • Radiated by the atmosphere as heat

Greenhouse Effect § Greenhouse gasses vibrate from excess heat and gain kinetic energy • Warms atmosphere • Positive feedback loop § Without greenhouse gases the world would be a cold uninhabitable place

The Greenhouse Effect

Video Clip § Green House Effect – Lesson 1

Ecosystems: What Are They and How Do They Work? Part 3 Energy Transfer

The Main Structural Components of an Ecosystem

How Organisms get Energy Autotroph- an organism that makes its own food § • Ex: photosynthetic plants, chemosynthetic bacteria § Heterotroph- an organism that cannot make its own food • Ex: humans

Predator or Prey? § Predation – act of one organism eating another organism • Predator – organism that does the eating • Prey – organism that gets eaten

Energy Roles: Producers- organisms that can make their own food § • Examples: plants, algae, some bacteria, some protists

Energy Roles: Consumers § Consumers- organisms that cannot make their own food; they are classified based on what they eat § Herbivore- organisms that eat producers (plants) • Examples: cows, deer, grasshoppers

Energy Roles: Consumers § Carnivore- organisms that eat only meat • Examples: wolves, killer whales

Energy Roles: Consumers § Omnivore- organisms that eat both meat and vegetation • Examples: humans, seal, chimps

Energy Roles: Consumers § Scavenger- organisms that eat things that are already dead • Examples: seagulls, vultures

Energy Roles: Decomposers § Decomposers - organisms that break down dead organisms and waste and return those nutrients to the ecosystem - Examples: bacteria, fungus § Anaerobic Respiration: byproducts are methane gases, ethyl alcohol, acetic acid, and hydrogen sulfide

Detritivores and Decomposers on a Log

A Food Chain

Food Chains and Webs § Food chains- show the flow of energy throughout organisms in a community or ecosystem • First organism is always a producer • Second organism is an herbivore • Third organism is a carnivore

Simplified Food Web in the Antarctic

Ecological Efficiency § When the deer eats the grass, it does not obtain all of the energy the grass has • Much of it is not eaten § When the wolf eats the deer, it does not get all of the energy from the deer • Much of it is lost as heat

Ecological Efficiency § No organism EVER receives all of the energy from the organism it just ate § 10% Law • Only 10% of the energy from one trophic level is transferred to the next

Energy Pyramids § Energy pyramids- shows the relationship between consumers and producers at different trophic levels in an ecosystem 45

Energy Pyramids • Most energy is available at the bottom of the pyramid 46

Energy Pyramids • As you move up the pyramid, each level has less energy available than the level below it 47

Tertiary consumers (human) Usable energy available at each trophic level (in kilocalories) Secondary consumers (perch) Primary consumers (zooplankton) Producers (phytoplankton) Heat 100 Heat 1, 000 Heat 10, 000 Decomposers Heat

Video Clip • http: //magma. nationalgeographic. com/ngexp lorer/0309/quickflicks/index. html 49

Your Turn! • Activity: Food Chains and Webs

Some Ecosystems Produce Plant Matter Faster Than Others Do § Gross primary productivity (GPP) • Rate at which an ecosystem’s producers convert solar energy into chemical energy stored in their tissues § Net primary productivity (NPP) • Rate they create and store energy minus the energy they use for homeostasis • Ecosystems and life zones differ in their NPP = GPP - R

Estimated Annual Average NPP in Major Life Zones and Ecosystems

Humans and NPP § Humans use, waste or destroy 20 -32% of the earth’s total potential NPP • They make up less than 1% of the Earth’s biomass!

Planet Earth Video Clip § Jungles • 20: 00 -25: 00 § Find an example of: • • • Producer Consumer (various) Decomposer Predator/Prey Food Chain – 3 levels

Ecosystems: What Are They and How Do They Work? Part 4 Range of Tolerance

Range of Tolerance for a Population of Organisms § Range of tolerance may vary in populations • Small differences in genetic makeup, health, and age

Several Abiotic Factors Can Limit Population Growth § 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 at or near the optimal range of tolerance

Strange Days on Planet Earth Video Clip § One Degree Factor • 4: 00 – 20: 00

Ecosystems: What Are They and How Do They Work? Part 5 Nutrient Systems

Recycling in the Biosphere § Energy and matter move through the biosphere very differently. • One-way flow of energy • Matter is recycled within and between ecosystems

Reservoirs § Temporary storage sites • Atmosphere • Oceans, lakes, rivers, and ponds • Underground deposits

Nutrients Cycle in the Biosphere § Biogeochemical cycles, nutrient cycles • • • Hydrologic Nitrogen Carbon Phosphorus Sulfur § Connect past, present, and future forms of life

Your Turn! § Cartoon Guide to the Environment • Questions 1 -6

Water Cycles through the Biosphere § Natural renewal of water quality: three major processes • • Evaporation Precipitation Transpiration Runoff § Fueled by energy from the sun

Hydrologic Cycle Including Harmful Impacts of Human Activities

Alteration of the hydrologic cycle by humans § Withdrawal of large amounts of freshwater at rates faster than nature can replace it § Clearing vegetation • Increases temperature and thus evaporation § Increased flooding when wetlands are drained

Water Pollution § Pavement prevents soil from absorbing water • Increases runoff and erosion § Only 0. 024% of water is accessible liquid freshwater • Groundwater deposits • Lakes, river, streams

Science Focus: Water’s Unique Properties § Properties of water due to hydrogen bonds between water molecules: • • Exists as a liquid over a large range of temperature Changes temperature slowly High boiling point: 100˚C Adhesion and cohesion Expands as it freezes Solvent Filters out harmful UV

Water Cycle Video Clip

Your Turn! § Cartoon Guide to the Environment • Pages 7 -9

Phosphorous Cycle § Phosphorus • Helps form important molecules like DNA, RNA, and ATP § Inorganic phosphate PO 43 - is released into the soil and water as sediments wear down. • Eventually enters the ocean, where it is used by marine organisms • Does NOT include the atmosphere

Phosphate Cycle • Organic phosphate moves through the food web and to the rest of the ecosystem. Organisms Land Ocean Sediments

Phosphorus Cycle with Major Harmful Human Impacts

Phosphorus Cycle Video Clip

Your Turn! § Cartoon Guide to the Environment • Page 23 • Question 11

Carbon Cycle § Carbon dioxide in atmosphere is taken in by plants § CO 2 is also given off by animals, decomposers, plants and burning fuels § Composes 0. 038% of the volume of the atmosphere

Carbon Cycle Depends on Photosynthesis and Respiration § Link between photosynthesis in producers and respiration in producers, consumers, and decomposers § Additional CO 2 added to the atmosphere • Tree clearing • Burning of fossil fuels

Carbon Cycle Equations Cellular Respiration C 6 H 12 O 6 + 6 O 2 6 CO 2 + 6 H 2 O +ATP Photosynthesis 6 CO 2 + 6 H 2 O sunlight C 6 H 12 O 6 + 6 O 2

Carbon Cycle § Marine sediments are earth’s largest store of carbon • Carbon is trapped between layers of sediment • Converted to fossil fuels when heated and compressed

Carbon Cycle § When living things die and decompose, their remains may someday become fossil fuels • Coal, oil, or natural gas • Burned to release CO 2

Greenhouse Effect § CO 2 in the atmosphere absorbs and retains heat • An overload of CO 2 now exists from burning fossil fuels § Component of Earth’s thermostat • Too much or too little causes major problems

Natural Capital: Carbon Cycle with Major Harmful Impacts of Human Activities

Carbon Cycle Video Clip

Your Turn! § Cartoon Guide to the Environment • Page 22 • Questions 9 + 10 § Carbon Cycle Game

Sulfur Cycles through the Biosphere § Sulfur found in organisms, ocean sediments, soil, rocks, and fossil fuels § Sulfate SO 4 2 - in the atmosphere • Sea spray, forest fires, dust storms § H 2 S and SO 2 released during volcanic eruptions (toxic)

Sulfur Cycle § Marine Algae produce dimethyl sulfide (DMS) • Involved in condensation of water (clouds) § DMS is converted to SO 2 and SO 3 and tiny droplets of sulfuric acid H 2 SO 4 (acid deposition) § Absence of Oxygen? • Bacteria convert sulfate ions into sulfide ions S 2 • React with metal ions and deposited as rock

Sulfur Cycles through the Biosphere § Human activities add SO 2 sulfuric acid and sulfate • Burn sulfur-containing coal and oil • Refine sulfur-containing petroleum to make gasoline and other heating products • Convert sulfur-containing metallic mineral ores • Copper lead and zinc

Natural Capital: Sulfur Cycle with Major Harmful Impacts of Human Activities

Your Turn! § Cartoon Guide to the Environment • Question 12

Nitrogen § Essential element § Needed for amino acids • Proteins! § Nitrogen gas makes up 78% of the volume of the atmosphere

Nitrogen Fixation § Nitrogen gas cannot be used by living things directly • Converted by lightening § Bacteria in soil and ocean convert nitrogen gas into ammonium (NH 4+) and ammonia �(NH 3) • Fixation

Nitrogen Fixation § (NH 4+) and�(NH 3) converted to nitrate ions • Nitrification

Assimilation § Used by plants to produce amino acids, proteins, nucleic acids, and vitamins • Assimilation

Nitrogen Cycle § Plants take in ammonia, ammonium, and nitrates through roots § Animals get nitrogen by eating plants or other animals that ate plants

Nitrogen Cycle § When the animal dies and decomposes the nitrogen is returned to the soil as ammonia • Ammonification § Plants take in the ammonia from the soil

Returning Nitrogen § Specialized bacteria in soil and bottom of lakes convert NH 3 and NH 4+ back into nitrates • Denitrification § Nitrates are converted to nitrogen gas and returned to the atmosphere

Human intervention in the nitrogen cycle • Additional NO and N 2 O • Burning fuels at high temperatures • Destruction of forest, grasslands, and wetlands • Add excess nitrates to bodies of water • Runoff • Remove nitrogen from topsoil • Harvesting nitrogen rich crops and irrigation

Annual Increase in Atmospheric N 2 Due to Human Activities

Nitrogen Cycle in a Terrestrial Ecosystem with Major Harmful Human Impacts

Nitrogen Cycle Video Clip

Your Turn! § Cartoon Guide to the Environment • Page 21 • Questions 7 + 8

Strange Days on Planet Earth Video Clip § Troubled Waters § Crown of Thorns and Nitrogen Fertilizers