Chapter 3 Ecology

Chapter 3- How Ecosystems Change (from your book)

Section 1
Succession- refers to the normal, gradual changes that occur in the types of species that live in an area.
If you never cut a lawn, in 20 years or so, it eventually would turn into a forest. Each stage of growth from lawn to forest is a stage of “succession.” We study succession in forest fires and volcano eruptions.

Primary Succession (1۫ succession)- Is the 1st species to colonize an area. They usually don’t require soil to survive. We call them the “pioneer species”. They can usually survive harsh conditions.
In primary succession new soil is being formed by the pioneer species. Example: Lichens grow and die adding nutrients to the ground. If the lichens grow on volcanic rock, they break down the rock into finer and finer pieces.
Primary succession begins in areas with no life at all. It can take hundreds or thousands of years to develop into a climax community.

Secondary Succession (2۫ succession)- This happens after soil is available. Seeds are carried to the place by the wind or by birds. Other wildlife may move in.
Wildlife is different in 2۫ succession than in 1۫ succession.
Secondary succession is usually shorter than primary succession, but it may still take a century or more.

Climax Communities- A community that has reached a stable stage. Balance has been reached and an ecosystem has been formed.
Fire is sometimes required for climax communities. The forest has evolved and adapted to fire. Seeds of evergreens are held in pine cones. Some cones of pine trees won’t open without fire.

Review and possible test Questions: What is ecological succession? Explain the difference between primary and secondary succession. What is the difference between pioneer and climax communities?

Section 2- Biomes- Areas in the world with similar and different climates.

The seven biomes-
1) Tundra-
a. Just south of the north pole
b. covered with ice for most of the year
c. Cold, dry, treeless, sometimes called a “cold desert”
d. The land is dark 24 hours a day because the sun never goes above the horizon (the sun only shows for a few days in the summer.
e. Only the top few inches thaw in the summer. Below is permanently frozen soil called “permafrost”. The soil has few nutrients.
f. Plants such as lichens, mosses, small shrubs, and grasses are adapted to drought and cold.
g. During the summer black flies, mosquitoes, and other insect fill the air.
h. Birds nest on the tundra during the summer.
i. Mammals such as mice, voles, lemmings, hares, caribou, reindeer, and muck oxen are found there.
j. Conservation problems such as oil pipelines, roads, and fences have interrupted migration and destructed habitat can take decades to recover.

2) Taiga
a. South of the Tundra
b. The world’s largest Biome
c. Cold, forest region dominated by cone-bearing evergreen trees
d. Warmer and wetter than tundra. Mostly snow precipitation.
e. Soils mostly thaw in the summer making it easier for trees to grow.
f. Little sunlight reaches the forest floor.
g. Moose, lynx, shrews, bears, foxes.

3) Temperate Deciduous forest
a. 4 seasons, Winter, Spring, Summer, Fall
b. Where we live.
c. Evergreen trees, deciduous trees
d. 90 percent of NH used to be farmland. After the land was stripped east of the Mississippi river, people moved out west and to the south, abandoning farm lands. Secondary succession kicked in and now we are forested again.

4) Temperate Rain forest
a. Pacific Northwest, southern Chile, New Zealand.
b. 200-400 cm of rain per year.
c. Needle-like trees including Douglas fir, western red-cedar, red-woods, sequoias, and spruce.
d. Black bear, cougar, bobcat, endangered northern spotted owl, salamanders
e. Logging is a big business in these forests (California Blue takes place in a Temperate Rain forest) Some forests are starting to be protected.

5) Tropical Rain forest
a. Warm and wet weather.
b. The most species on earth are found in tropical rain forests because the climate has stayed the most stable throughout the earth’s history giving organisms a lot of time to adapt into amazing things.
c. Zones:
i. Forest Floor- Mammals, insects, bushes
ii. Understory- Cool and dark under the canopy, insects, reptiles, amphibians
iii. Canopy- Full of life of all types
iv. Emergents- Giant trees, birds, insects, and more.

d. Human impact- Uneducated farmers use slash and burn agriculture techniques, the crops use all the nutrients quickly and the farmers have to clear more land. This breaks the transpiration part of the water cycle and causes irreversible damage to the ecosystem.
e. Logging may be prohibited but not enforced

6) Desert- The driest biome on Earth.
a. Less than 25 cm of rain each year. Some get no rain for years.
b. Thin sandy soil that contains little nutrients
c. Any plants are spaced far apart due to a lack of water.
d. Plants and animals are adapted to dryness
e. Cacti, kangaroo-rats (never need to drink water), bats, coyotes

7) Grasslands
a. Dominated by grasses
b. Lack of moisture prevents the growth of forests.
c. Prairies, savannas, and plains are other names for grasslands.
d. Mammals graze on stems, leaves, and seeds of grass plants
e. Kangaroos, wildebeests, zebras and many others live there.
f. Grasslands are good for certain types of farming.

Review and test questions- Which two biomes are the driest? Compare and contrast tundra and desert organisms. Why does the soil of tropical rain forests make poor farmland? What are some animal adaptations that allow them to live in specific biomes?

Section 3- Aquatic Ecosystems
1) Rivers and streams-
a. The faster a stream moves, the clearer it is, and the higher the oxygen content is.
b. The slower, the more plants and organisms not well adapted to fast water.
c. Human impact- In fairly recent history we dumped sewage into rivers and streams. Throughout the world this is still practiced.

2) Lakes and Ponds
a. Ponds move less than lakes and contain more plant growth.
b. Lakes are larger and deeper than ponds. Plants are limited to the shoreline. Colder temps and less light can penetrate deep water.
c. Ponds tend to be high in nutrients due to the excess plant growth

Water Pollution-
Fertilizer runoff and sewage can lead to algae-blooms and overgrowth of plants in ponds.
This reduces the oxygen level which makes it harder for some organisms such as fish to survive.
Sewage needs to be treated before going into the environment.

Wetlands-
Regions that are wet all year round.
Other names are swamps, everglades, bogs, and fens.
They are very fertile ecosystems
Plants adapted to waterlogged soil live there.
Beavers muskrats, alligators and some turtles live there along with migratory birds.
Economic value for cranberries, fish, and shellfish
Development in these areas is now prohibited in some places
Think about it: What would happen to coastal wetlands if the oceans rise due to global warming?

Saltwater ecosystems-
95 % of water on earth contains salt.
Open oceans- Tons of different forms of life.
Zones have been created based on the amount of light penetration.
Coral reefs- the most diverse ecosystems of the world
They are formed over thousands of years from the buildup of calcium carbonate. When corals die their shells still remain.
Reefs don’t adjust well to change and could die and not come back.
They can “bleach” from the increased temperature of the ocean due to global warming.
Seashores- Lots of salt-water ecosystems are in the world.
All life is determined by the rise and fall of tides.
The intertidal zone is the area of shoreline with tides.
Organisms need to be adapted to huge temperature differences, air, water, and waves.

Estuaries- The areas where rivers meet oceans.
Mixtures of fresh and salt-water.
Other names are bays, lagoons, harbors, inlets, and sounds.
They are extremely fertile due to high amounts of nutrients.
Algae, salt-tolerant grasses, shrimp, crabs, clams, oysters, snails, worms, and fish.
Estuaries are nurseries for many species of fish.

Questions- What are the similarities and difference between a lake and a stream? Why are there few plants at the bottom of deep lakes? What adaptations are necessary for organisms that live in the intertidal zone?

This week Jan 17th, 2006

This week we will be finishing our global warming papers, correcting our "open-book" tests, and getting into chapter 2. Next time you know there's an "open-book" test, you might want to study.
Don't be a passive student, just along for the ride. Be the driver.
"There are no shortcuts to any place worth going"
This is the start of a life-long education.
Don't cheat yourself by not doing the reading and relying on me to give you the lecture.
You will find yourself ill prepared, time and time again!

Mr. Talon

Ecology Chapter 2 notes

Chapter 2- Ecology- Many factors contribute to organism success
Vocabulary: Biotic, abiotic, atmosphere, soil, climate, evaporation, condensation, water cycle, nitrogen fixation, nitrogen cycle, carbon cycle, chemosynthesis, food web, energy pyramids

Environmental factors-
Biotic factors- “biotic” means living- features of the environment that are or where once alive.
Abiotic factors- “a” means not “biotic” means living- non-living physical features of the environment.
What’s some of the most important abiotic factors in the environment? Water and oxygen

Abiotic factors-
1) Air- the atmosphere is 78 % nitrogen, 21 % oxygen, and small amounts of Carbon dioxide, argon, neon, helium, and others.
Organisms use air for feeding body cells in a process called respiration.

2) Water- most organisms are 50-95% water. The following processes only take place with water: respiration, digestion, photosynthesis.

3) Soil- The topmost layer of the earth’s crust. Soil contains rocks, minerals, dead organisms, and air. Soil is biotic and abiotic because it contains dead and living organisms and other non-living factors. Humus- decaying matter found in the soil

4) Sunlight- All life on earth relies on producers that get their energy from the sun. Photosynthesis!!

5) Temperature- Organisms survive mostly at temperatures from 0 deg C to 50 deg C. (Water freezes at zero degrees C)

Aside- Why is it hotter at the equator? Answer: The equator gets direct sunlight strait on. The poles get sunlight at an angle. This keeps them cooler. In winter the earth tilts causing less sun to hit at higher latitudes. This causes lower temperature. The southern hemisphere is in summer when we are in winter.

Climate- Refers to an areas average weather conditions. Includes temperature, precipitation, and wind. Temperature and precipitation are the most important for living things.
Wind- How is it created? Air molecules are heated by the sun. These warmer molecules rise up (warm air rises) and a current is created. This current is wind.

Review questions. What’s the difference in abiotic and biotic factors? What are the examples of each? What parts of air are required for life? Why is soil both biotic and abiotic.

Section 2- Cycles in nature.

The Water cycle- Water cycles through the environment through a number of different processes.
Evaporation- liquid water is converted to a gaseous water and rises into the atmosphere
Condensation- Gaseous water is converted into liquid water
Transpiration- evaporation directly from plant leaves.
Precipitation- general term for water that falls from the sky as solid or liquid
Respiration- organisms breathe out gaseous water

The Nitrogen Cycle-
Nitrogen is in all living things. It is in DNA and proteins and therefore is vital to life. Plants use Carbon Dixoide, Nitrogen, Phosphorus, and Potassium to grow.
Plants cannot use the nitrogen that exists in the atmosphere. They have to get it from fertilizers or from a process called Nitrogen fixation. In this process bacteria transform atmospheric nitrogen into a more useable form called ammonium.
Bacteria have a symbiosis with plants.
Legumes such as peas, and beans have unique nodes on their roots that house bacteria. Bacteria provide food for the plant. Mutualism!!




Soil Nitrogen-
Growing crops takes a large amount of nitrogen and other elements out of the soil.
Farmers need to put it back by using fertilizers.
They may add synthetic fertilizers containing N, P, and K.
They occasionally use organic fertilizers like cow manure.
Farmers occasionally rotate crops with ones that use nitrogen fixation. These legumes put nitrogen back into the soil and other crops can be grown there in future years.

Carbon Cycles-
Plants remove CO2 from the atmosphere.
Things that add CO2 to the atmosphere
Wood burning including heating and forest fires
Volcanoes
Organism respiration
Burning fossil fuels including coal, natural gas, and oil products (#1)
Where did all the fossil fuels come from?
FOSSILS!!! More accurately… all the fossil fuels on earth came from the billions of organisms that have lived on earth in the past 3.5 billion years.
All organisms are carbon based, when their bodies break down after death their carbon enters the ground and over billions of years turns into oil.
Isn’t it interesting that we could be possibly using up all the oil created though billions of years of decay in just a couple hundred years? It’s mind boggling!





Section 3. Energy- Where does it come from? The sun of course!
Photosynthesis-Sunlight+ 6H2O + 6CO2 ----------> C6H12O6+ 6O2
Light is converted into chemical energy

Chemosynthesis- How do the bacteria and organisms at the bottom of oceans make energy without the sun?
o Organisms use sulfur and other chemicals that come from oceanic vents to make their energy. Molten lava flows through these vents and provide the energy.
o It is thought that the first organism on earth probably used chemosynthesis due to a lack of sunlight and an abundance of harsh chemicals.
Food Chains- Show feeding relationships in an ecosystem





See the food chain below-

A food web is more complex and shows all possible feeding relationships. See below


An energy pyramid shows how much energy is lost at each energy level. The energy remaining on any step is only 10% of the last step. The first step of any energy pyramid is a producer. This limits the number of links in a food chain. (the max is usually 5)
Review Questions- Why is the presence of carnivores positive evidence of a healthy forest?
What’s the difference in Chemosynthesis vs. Photosynthesis?
Why is there a limit to the number of links in a food chain?

Chapter 1 ecology

Ecology Notes
Chapter 1

Native Americans lived “conservation” as a way of life. This was the idea of sustainable living.
Example: Cheyanne bison hunt
Strict rules on killing more bison then needed
Used all parts of the animal so none was wasted
Meat eaten for food
Fat used for cooking
Bones used for tools
Hides were used for clothing
Stomachs were used for water pouches.

It was a Native American belief that people must cooperate with nature so that revival and rebirth can continue.

The Mayans believed that cutting down a tree unnecessarily shortened one’s life. Although this was thousands of years ago, there is some truth in this. Trees and plants remove carbon dioxide from the air and reduce global warming.

Quotes from Chief Seattle:
Every part of all this soil is sacred to my people. Every hillside, every valley, every plain and grove has been hollowed by some sad or happy event in days long vanished. The very dust you now stand on responds more willingly to their footsteps than to yours, because it is rich with the blood of our ancestors and our bare feet are conscious of the sympathetic touch.
We know that the white man does not understand our ways. One portion of the land is the same to him as the next, for he is a stranger who comes in the night and takes from the land whatever he needs. The earth is not his brother, but his enemy - and when he has conquered it, he moves on. He leaves his fathers' graves, and his children’s birthright is forgotten.
The Indian prefers the soft sound of the wind darting over the face of the pond, the smell of the wind itself cleansed by a midday rain, or scented with pinon pine. The air is precious to the red man, for all things are the same breath - the animals, the trees, the man. .
The whites, too, shall pass - perhaps sooner than other tribes. Continue to contaminate your own bed, and you might suffocate in your own waste.
When the buffalo are all slaughtered, the wild horses all tamed, the secret corners of the forest heavy with the scent of many men, and the view of the ripe hills blotted by talking wires, where is the thicket? Where is the eagle? Gone.
We are part of the earth and the earth is part of us.
There is no quiet place in the white man’s cities, no place to hear the leaves of spring or the rustle of insects’ wings. Perhaps it is because I am a savage and do not understand, but the clatter only seems to insult the ears.
If the Native Americans lived “conservation,” then what is conservation?
_____________________________________________________________________
Definition: The practice of modifying human behavior to preserve Earth.

Ecology studies how all species on Earth are connected.

Ugly fact- In 1950 30% of the earth’s land was covered by rainforest, now it is only 7%.


Section 1- The Interactions of Life

Vocab- Biosphere, ecosystem, ecology, populations, community, habitat

Biosphere- The part of the Earth that supports life. 3 parts: the top of earth’s crust, the water, and the atmosphere.
- The biosphere has many different environments such as polar, desert, ocean, etc.

Life on Earth- Very lucky, we are the 3rd planet from the sun
- Any closer too hot, any further too cold

Ecosystems- An ecosystem is all the organisms living in an area and the non-living features of that environment.
-ex: a Prairie’s living parts contain bison, grass, birds, insects, and bacteria. Its non-living parts contain water, temperature, soil, sunlight, and air.

Ecology: The scientific study of the interactions that determine the distribution and abundance of organism.

Ecologists study populations. A population is made up of all the organisms in an ecosystem that belong to the same species.

Ecologists study how populations interact.
-ex: Bison grazing affect prairie grass, birds and insects are in the grass, birds eat the insects.

A community refers to all populations in an ecosystem.
A habitat is the place an organism lives.

Review questions: What’s the biosphere? What’s ecology? What is a community vs. a population, how do they relate?

Section 2- Populations

Competition- Organisms in the same population compete for a variety of things
Food and space
Growth Limits
mates

Population Size- Counting populations can help identify those organisms in danger of disappearing.

The size of a population that occurs within a specific area is the population density.

Measuring- Different models exist for estimating populations. Some include mark-recapture techniques which involves live trapping. The organisms are re-captured and then mathematical equations are used to estimate the population.
Sample counts can be taken if you want to know the number of animals in a particular area. Ex. How many mice are in a 100 acre forest? Count the number of mice in 1 acre and multiply by 100.

Limiting factors- Organism’s need resources. They can’t grow or will stop growing or reproducing if a resource runs out.
-A limiting factor is anything that restricts the number of individuals in a population.

Carrying capacity (K)- The largest number of individuals of 1 species that an ecosystem can support over time. The Earth’s carrying capacity is estimated to be about 10 billion.

Changes in Populations- Birthrates and Death rates
Death>Birth- population gets smaller
Birth>Death- Population gets larger see pg 18 pop. Growth chart

Exponential Growth: The larger a population becomes, the faster it grows.
- Exponential growth occurs till it reaches carrying capacity or K. When this happens it is limited by a resource. For humans it is believed to be fresh water.
See human growth graph pg 19. 6.5 billion now, 10 billion by 2050.

Section 3- Interactions within communities.

Most energy on Earth comes from the sun. Directly or indirectly

Producers- Make their own energy. Plants and photosynthesis

Consumers- Cannot make their own energy. They eat other organisms for their energy.
- Herbivores- Eat plants
- Omnivores- Eat plants and animals
- Carnivores- Eat animals
- Decomposers- Break down dean organisms and waste

Food chains- Model of the feeding relationships in an ecosystem.
Question- What happens when you break a chain?

Symbiotic relationships- close relationships between species
Types: Mutualism (+,+) Both organisms benefit from the relationship
Commensalism (+,o) 1 organism benefits, the other is not helped or affected
Parasitism (+,-) 1 organism benefits, the other is harmed

Niches: An organism’s specific role in its community; its specialized job. Each organism can live in the same area of a community because they use different resources, they have their own role. If two different species need the same niche and have the same job, they will compete till one wins.

Predator/ Prey: The presence of predators increases the number of different species that can live in an ecosystem. They limit populations, therefore, food isn’t as limited.

Cooperation- Some populations work together such as bees, deer, and ants. They have different jobs and tasks. They have a common goal of reproductive success and survival.

week of January 9th

I would like to thank my students for taking such an interest in global warming. For the select few who still think global warming is not caused by humans I hope you will still start becoming an activist. We can all do little things in our lives to preserve this great planet for future generations such as recycling, turning off appliances and lights, and buying more fuel-efficient cars.

You can see the flash video on global warming at www.leonardodicaprio.org and click on the global warming video link.

Unfortunately, we don't have the mobile lab till next week so we have to take a break from writing our papers. I can tell that you are disappointed.

For the month of January we are going to study ecology. Ecology is the scientific study of the interactions that determine the distribution and abundance of organisms. Basically, where are the organisms? Why are they there? What part of their behavior lets them live where they do? How do they interact with each other?

We will be discussing conservation a lot. Conservation was started by the Native Americans. It is the practice of modifying human behavior to preserve Earth.

You can see from this definition why we are studying this after global warming.

See you in class.
Mr. Talon