PS 6.3-6.6

Environmental Science

StandardsB-6.3 Illustrate the processes of succession in an

ecosystemB-6.4 Exemplify the role of organisms in the

geochemical cycles (including the cycles of carbon, nitrogen, and water).

B-6.5 Explain how ecosystems maintain themselves through naturally occurring processes (including maintaining the quality of the atmosphere, generating soils, controlling the hydrologic cycle, disposing of wastes, and recycling nutrients).

B-6.6 Explain how human activities (including population growth, technology, and consumption of resources) affect the physical and chemical cycles and processes of Earth.

Vocabulary Agriculture Technology Alternative Energy Carbon Cycle Carrying Capacity Consumption of Resources Denitrification Deposition Ecological Succession Geochemical Cycles Geosphere Greenhouse Effect Hydrologic Cycle Industrial Technology Nitrogen Cycle

oNitrogen FixationoNon-Renewable ResourcesoOzone LayeroPioneer SpeciesoPopulation GrowthoPrimary SuccessionoRenewable ResourcesoSecondary SuccessionoSinkoSoil ErosionoSustainability oTechnologyoWater Cycle

Section 1: Succession in Ecosystems

1) Succession is a series of changes in an ecosystem when one community is replaced by another community because of changes in biotic and abiotic factors.

a) Succession occurs in all ecosystems.

2. Primary Successiona) Takes place in an area that has

not been inhabited before by plants and animals

i. Examples: rock surfaces formed by lava, rocks scraped clean by glaciers, and city streets

Primary Successionb) Begins with organisms that can grow

without soili. Lichens and some mosses break down rocks

into smaller species. These are examples of pioneer species.

ii. When there is enough soil and nutrients small plants start to grow and break the rock down further which makes more soil.

iii. Seeds from other plants and small trees grow.iv. As species grow and die their decomposed

bodies add nutrients to the soil and even larger plants are able to populate the area.

Lichen

http://commons.wikimedia.org/wiki/File:Lichen_DSC00612.JPG

http://www.thbfarm.com/Gardens_for_Nature.html

http://frankwinters.wordpress.com/2007/01/09/lettuce-lichen-and-henry-david-thoreau/

Primary Succession

3) Secondary Successiona) Begins in an area where there

used to be an community and has well-formed soil

b) Examples: abandoned farmland, empty lots, clear-cut forest areas, areas burned by forest fires.

Secondary Successionc) When something like a hurricane,

wildfire, or human activities destroys a community secondary succession takes place.i. It is like primary succession in the

later stages after soil has formed.ii. When the disturbance is over, the

ecosystem restores the original condition of the community.

Secondary Successiond) Occurs faster than primary

succession because soil is already present

i. When disturbances happen often or are intense, the area will mostly have the species that are present in the early stages

ii. When disturbances are moderate, the area will have habitats at different stages.

Section 2 – Biogeochemical Cycles

Biogeochemical Cycles1) Biogeochemical cycles are the

movement of forms of matter through the living and nonliving parts of an ecosystem.

a) Matter changes forms but is never created or destroyed.

b) In biological systems matter is used over and over again in different forms.

2) Carbon Cycle

a)Carbon is the major part of biochemical compounds.

b)Carbon is the major part of living things (proteins, carbohydrates, lipids, nucleic acids).

Carbon Cycle

fossil fuels

photosynthesis

carbon dioxidedissolved in water

decompositionof organisms

respiration

carbondioxidein air

photosynthesis

combustionrespiration

c) Carbon is found in the atmosphere and in many minerals, rocks, and fossil fuels (gas, petroleum, coal).

d) Anything that stores carbon is called a sink.

i. Oceans are the Earth's largest carbon sinks

ii. Plants and soil are also carbon sinks.

Carbon Cyclee) Ways Carbon is Recycledi. Photosynthesis

1) Plants and other photosynthetic organisms use carbon dioxide from the atmosphere and turn it into simple sugars.

ii. Respiration1) Organisms (like us!) break down glucose

in our bodies and carbon dioxide (CO2) is released into the atmosphere when we breath out.

Carbon Cycleiii. Decomposition

1) When organisms die, decomposers break the bodies down into carbon compounds that enrich the soil and are eventually released into the atmosphere as CO2.

iv. Conversion of biochemical compounds1) Organisms store carbon as

carbohydrates, proteins, lipids (fats), and nucleic acids in their bodies.

Carbon Cyclev. Other ways carbon may be released:

1) Combustion: Burning of wood or fossil fuels – this releases Co2 into the atmosphere.

2) Weathering of rocks: Bones and shells fall to the bottom of oceans or lakes and become a part of the rocks, such as calcium carbonate. When these sedimentary rocks weather, carbon is released into the ocean and eventually into the atmosphere.

3) Nitrogen Cycle

a) Nitrogen is needed to build proteins in organisms and is found in materials that compose soil and aquatic sediments.

b) Elemental nitrogen (N2) is found in the atmosphere

Nitrogen Cyclec. Ways organisms recycle nitrogen:i. Nitrogen-Fixation

1) Nitrogen-fixing bacteria which live in the soil, roots of plants, and aquatic ecosystems, convert nitrogen from the air into forms that plants can use

ii. Intake of nitrogen into organisms1) Plants take in nitrogen through their

roots in the form of ammonia and nitrate. This is how nitrogen enters the food chain.

Nitrogen Fixation

http://www.jic.ac.uk/corporate/about/publications/advances/issue_6.html

Bacteria live in these little nodules

http://io.uwinnipeg.ca/~simmons/16cm05/1116/16monera.htm

A bunch of bacteria in a root nodule

Nitrogen Cycle

nitrogen inatmosphere

animals

denitrifyingbacteria

nitrifyingbacteria

nitrifyingbacteria

ammonium

ammonification

decomposers

plant

nitrogen-fixingbacteria in soil

nitrogen-fixingbacteria in

roots

nitrates

nitrites

iii. Decomposition1) When an organism dies or from

animal waste, decomposers return nitrogen to the soil.nitrogen in

atmosphereanimals

denitrifyingbacteria

nitrifyingbacteria

nitrifyingbacteria

ammonium

ammonification

decomposers

plant

nitrogen-fixingbacteria in soil

nitrogen-fixingbacteria in

roots

nitrates

nitrites

Nitrogen Cycleiv. Denitrification

1) Denitrifying bacteria break down nitrogen compounds in the soil and release it into the atmosphere.

4. Water Cycle (Hydrologic Cycle)a) water is necessary for all life

processes in living things.b) Water is in the atmosphere,

surface of the earth, underground, and in organisms.

c) The water cycle is driven by the heat from the sun because it causes evaporation

Water Cycle (Hydrologic Cycle)

precipitation condensation

transpirationevaporation

water storagein ocean

surfacerunoff

lake

groundwater

seepage

Water Cycle (Hydrologic Cycle)d) Ways organisms recycle water:i. Intake of water

1) Organisms use water to perform life functions

ii. Transpiration1) The release of water back into the atmosphere

by plants

iii. Respiration 1) Organisms produce water as a by-product of

metabolizing food

iv. Elimination1) Organisms need water to help with eliminating

wastes

8)Water Cycle

This cycle is maintained by the sun and weather

How the water cycle purifies waterevaporation Evaporated water has no impuritiesWater seeps through soil and rock is filtered of impuritiesAs water flows down streams, heavier particles settle out which leaves purified water to travel to the ocean

Section 3 – Ecosystem Care

1) Naturally occurring processes on Earth are needed to help ecosystems to maintain the materials that organisms need.

2) The earth is made of 4 parts:a) Biosphere (inhabited by life)b) Atmosphere c) Hydrosphered) Geosphere

i. These systems must interact efficiently for an ecosystem to maintain itself

3.) Maintaining the Quality of the Atmospherea) Oxygen and carbon dioxide are cycled

through the atmosphere (process is photosynthesis and respiration)

i. Plants use carbon dioxide in the air to make their food and give off oxygen as a waste product

b) Animals use the oxygen for respiration and release carbon dioxide as a waste product.

oxygen

respiration

carbondioxide

photosynthesis

Maintaining the quality of the atmosphered) The oxygen produced during

photosynthesis is also used to make up the ozone layer which protects the biosphere from the Sun’s radiation.

e) Water also maintains the atmospherei. When water vapor condenses, dust and

other particles are removed from the atmosphere and falls with the rain or snow. (The air gets cleaned!) Air gets washed!!

4. Greenhouse Effecta) Carbon dioxide, oxygen, and water vapor

trap heat energy to help maintain Earth’s temperature

b) Greenhouse gases do not let heat pass through them very well, so heat that the Earth releases stays trapped

c) The amount of carbon dioxide depends on how much photosynthetic organisms are absorbing it.

Greenhouse Effect

Amount of CO2 in

the atmosphe

re

Green

house effect

Average Global

Temperature

Plant cover

on earth

Rate of photosyn

Thesis

Amount of CO2

absorbed by plants

Amount of CO2 in

the atmosphe

re

Higher Increases

Increases

Increases

Increases Increases Decreases

Lower Decreases

Decreases

Decreases

Decreases Decreases Increases

5) Global Warminga) Global warming is the trend of increasing

global temperaturesb) Scientists believe the increased

temperatures are from greenhouse gases given off by industry and automobiles

c) Global warming is a hotly debated topic - some scientists believe global warming is a result of climate patterns

d) There is concern over how these temperature changes will affect ecosystems and especially biodiversity

6) Air Pollutiona) Most air pollution comes from the burning of

fossil fuels such as gas and oil.i. Smog is air pollution that results from the

interaction of sunlight and pollutants including particulates (tiny particles of dust, metal, and fuel).

ii. Acid rain is a type of precipitation produced when pollutants cause the rain's pH to drop (makes it more acidic).

1) Acid rain makes lakes and streams more acidic, threatening water supply and the habitats of many species. It also damages plants.

7) Generating Soilsa) Soil is part of the 1. geosphere – they are

2. always being formed and erodedb) Soil is made of: 3. minerals, organic

matter, water, and airc) Organic matter – 4. was once part of a

living thingd) Soil is formed from by a. weathering of

inorganic materials by b. wind, water, and ice and the c.decaying of organic materials

Generating Soild) 6. Wind, water, and ice

cause soil erosion and deposition which moves soil from one place to another

e) Plants help keep the process of soil production to be consistent with the process of soil erosion

I. 7. The plants roots hold the dirt in place, and also block wind from blowing the dirt)

f) Soil is needed for 8.succession to take place.

Water Pollutionc) Water Pollution

i. 1. Runoff from farms and cities may contain toxic chemicals and trash that can 2.disrupts the stability of freshwater lakes and streams.

ii. 3. a stable ecosystem is balanced and healthy

1) Ex. fertilizers from farms 5.can cause algae overgrowth which 6.lowers the amount of oxygen for the fish

2) An indicator speci es 7.gives a sign that an ecosystem is being affected such as frogs with deformities from coming into contact with toxic chemicals

3) Biomagnification takes place when a pollutant moves up the food chain as predators eat prey.

4) 8. The species at the top are affected the most.

9) Disposing of Waste & Recycling Nutrientsa) Waste materials from organisms are

decomposed by bacteria or other organisms

b) Nutrients cycle from organisms to the environment and back by the geochemical cycles

10. Human Roles in Geochemical Cyclesa) 6.People depend on the

resources and cycles on earth to provide clean water, clean air, and soil that can support crops.

b) Human activities such as7. population growth, technology, and using resources affect the cycles and processes on earth.

Section 4 – Population Growth

1. Carrying Capacity1) Energy, water, oxygen, and nutrients

determine the carrying capacity of humans on earth.

2) In order for humans to have sustainability, there needs to be a balance between Earth’s resources and carrying capacity, the needs of humans, and the needs of other species on earth

2. Population Growtha) Population growth has grown

exponentiallyb) The population rate naturally slows as the

Earth nears carrying capacity as the death rate increases and the birth rate decreases due to:

i. Food and water shortagesii. Pollutioniii. Disease

http://www.treehugger.com/files/2009/05/world-population-growth-good-news-asia-pacific-rates-starting-to-decline.php myafrica.wordpress.com http://serc.carleton.edu/quantskills/methods

/quantlit/popgrowth.html

3. Increasing Population Problemsa) Clean water runs low if water is being

used up faster than it can be purifiedb) More waste is produced than can be

managed. Can also be expensive to deal with

c) Fertile soil for agriculture is lost when land is cleared

i. Worldwide demand for land has led to deforestation

Increasing Population Problemsd) Areas of the world with very high

populations have low amounts of fertile soil, clean water, and available land. This affects the water, nitrogen, and carbon cycles as well as soil regeneration.

http://www.bnvillage.co.uk/news-politics-village/101777-does-obama-administration-want-reduce-africa-s-population.html

Section 5 - Human Activity on Earth

1. Technologya. Technology applies scientific knowledge

to find solutions and develop products that meet the needs of humans. Technology has helped humans, but has also caused pollution.

b. Now humans depend on technology to provide cleaner ways to deal with waste and to clean up pollution.

c. Technology agriculture and industry can either have a positive or negative impact on Earth.

2. Agricultural Technologya) Technology has

improved the ability to grow crops to sustain a growing world population.

b) Sustainable practices can conserve fertile soil and reduce erosion

Agricultural Technologyc) Farm machinery use

nonrenewable resources and can contribute to erosion and air pollution.

d) Fertilizers, pesticides, fungicides, and livestock waste can change the soil and have both positive or negative effects on the different cycles we are learning about.

3) Industrial Technologya) helped to develop communication,

transportation, and industry.b) chemicals like CFCs can deplete the

ozone layer. The ozone layer helps protect the earth form ultraviolet waves.

c) Getting rid of old technological equipment has become a problem.

CFCs were once used in air conditioners

Industrial Technologyd) Burning fossil fuels is needed for industry

and transportation and helps sustain the growing human population; however:

i. It increases greenhouse gases (carbon dioxide) which many scientists believe increase global temperatures

ii. It produces acid rain.

4) Alternative Technologya) Using natural renewable resources (wind,

water, geothermal, or solar energy) decreases the burning of fossil fuels

b) Nuclear energy is another energy source. A big problem with nuclear energy is where to store the waste produced.

5) Consumption of Resourcesa) As the population increases and

technology expands, the need for resources increases. There is only a limited supply.

b) Resources such as food, clean water, and timber are renewable.

i. Renewable resources have factors that limit their production

ii. Ex: growing grain requires land, fertile soil, and clean water

Consumption of Resourcesc) Nonrenewable resources cannot be

produced at the rate they are consumedi. Minerals and metals are important for

industry but are decreasing in availabilityii. Minerals are formed so slowly that they

take to long to replace

d) Sustainable use of resources can be accomplished by not using them as much, reusing products, and recycling waste.