Biology Notes – Ecology

Biosphereo Where you find living things.o Contains:

Atmosphere (air) Hydrosphere (water) Lithosphere (ground)

Ecologyo The study of the interactions among organisms and their environment .o Living (biotic) and non-living (abiotic) factors are observed.

Biotic Living things Factors:

Population A group of organisms in a given area in the same species The speed at which a population grows is affected by their environmental recourses.

Carrying capacity - (an imaginary number) the maximum population that can be supported by recourses in the environment.

Ex: On a chart the population goes up and then goes down and so on. (looks like a squiggly line)

Effected by little food, disease, and competition Community

Several populations in one area Ecosystem

Several different communities together. Food webs/chains

At the bottom, there are autotrophs. Get their energy from the sun (plants, some bacteria, etc.)

Then, there are heterotrophs which eat the autotrophs. (producers) Some only eat plants (herbivores) Some only eat meat (Carnivores) Some eat both (Omnivores) Some eat only dead remains (decomposers)

There will always be more autotrophs in any environment than any other organisms. They do not rely on other living things.

Decomposers are important because they clear away dead things to make space and they put nitrogen into the soil.

Nitrogen is important because there is nitrogen in amino groups (protein) and it is also in DNA in the nitrogen bases (ATCG)

The nitrogen in the soil is consumed by plants

Abiotic Where they live and where they survive. Their environment Factors:

Light The intensity being strong or weak The duration of sunlight in, for example, Distance north/ south of the equator (where sun strikes)

Temperature Hot or cold poses different difficulties. Affected by Latitude and Altitude

Very high/ very low altitude = cold Colder at the poles Warmer at the equator

It can snow on the equator in the Andes Mountains. Water

Amount of water and precipitation

The kind of water forms Rain, snow, dew, fog

The chemicals, salt, etc. in the water Soil

Decomposed organisms, rock, minerals The amount of soil and contents, pH, minerals, etc. in the soil.

Symbiotic relationships Means that organisms are living together

Mutualism - both organisms benefit (+/+) Ex: E-coli and humans. E-coli need us to survive and they help us break down our

food. They also make Vitamin K Parasitism - one benefits (parasite), the is harmed (host) (+/-)

Ex: Like germs when you have a cold. Also like ticks and tapeworms. The host usually does not die .

Commensalism - one benefits, other is unaffected. (+/o) Ex: When pilot fish benefit from shark gills.

Competition Relationships Because there are limited resources, organisms must compete for them. Most competition is for mates.

Habitat - where the organisms lives Niche - an organisms role in an ecosystem

*you compete more with organisms in your own niche.o Recycling of Materials

o We use the same air as dinosaurso The same elements: nitrogen, carbon, oxygen, water cycles.

o Nitrogen Cycle o The most common way this happens is that plants and animals decompose and the decomposers eat

them and put special nutrients back into the soil. This includes nitrogen. Then the plants absorb the nitrogen and herbivores eat the plants and then they die and the decomposers eat them… etc.

o As humans, we throw artificial sources of nitrogen in the soil. Fertilizer. Some of the extra fertilizer can change the pH therefore killing special bacteria and slowing down the decomposition therefore hurting the whole food chain.

o CO2 and oxygen cycles o CO2 and oxygen usually get recycled together. o In photosynthesis, they get CO2 and release oxygen. We get oxygen and release CO2. o The waste product of one reactions is a reactant in another.

We are impacting CO2 in the air. This is bad because CO2 is trapping heat in the atmosphere. Burning fossil fuels.

This is called the greenhouse effect which is a definite thing that is happening. Also, the glaciers are melting because of this, as well, causing a decrease in cold habitats and

making the oceans colder and deeper which causes more floods and changing the global temperature since most of the earth is ocean.

o Some people say it may cause very violent storms or a second ice age. They also believe that the greenhouse effect is causing global warming, however, the greenhouse effect has nothing to do with the ozone layer.

REMEMBER: The greenhouse effect, global warming, and the ozone layer are all completely different.

o Water cycleo The way water gets recycled is by physical changes to water.

Clouds are made of water vapor When the cloud gets cold and heavy, it rains The rain goes into the hydrosphere (lakes, rivers, etc.) Then the water evaporates back into the atmosphere. We are putting sulfur into the air causing acid rain. That's bad!

o Successiono Regenerating an ecosystem is called succession. o Ex: How you can wipe out an area with a forest fire, but then the area rebuilds itself. o The first time it happens is called primary succession

Nothing has lived there yet.

Ex: Volcanic rock creates an Island. Lichen (a symbiotic relationship between bacteria and algae which is very important) clings to the volcanic rock from the ocean. They create soil. Takes thousands of years. Next, plants grow and then animals. This creates a climax community.

Making soil is the LONGEST part.o Secondary succession is rebuilding.

After there has been a catastrophe in that climax community, the environment rebuilds itself after a few years. It takes less time because there was already soil there.

o Succession in watero Lakes dry upo Soil is madeo Plants growo Euthrophication is when humans speed up succession by killing the fish and plants with chemicals. Its is

BAD!o Biome

o A large geographical region that has a particular type of climax community, either plants or animalso You can figure out a biome by the flora (plant life) and fauna (animal life).

o Aquatic Biomeso Marine biomes have salt concentration of approximately 3% and cover approximately 75% of earth’s

surface. o Species need more water in their cells.o Freshwater biomes are usually characterized by salt concentration of less than 1%.o Species need more salt in their cells.

o Depths of aquatic biomes.o The photic zone is the zone through which light penetrates and photosynthesis can occur.o The aphotic zone is where very little light is. No producers o The benthic zone is the very bottom where the dead stuff goes and where the decomposers are.

o Estuarieso Where freshwater and salt water meets.o It is a tricky area because depending on the current, the salinity can be different and the species have to

adapt for both.o Terrestrial o Tropical Rainforests

o Lots of strong lighto By the equatoro Lots of rain fall every dayo Animals have to be adapted to the humidity, rain, mildew and mold, etc.o There is a lot of nutrient and rich soilo Deforestation

One of the problems here is that we cut down so many trees This destroys the animal homes and makes less oxygen and more CO2. It can also add to the

greenhouse effect and kill off species of trees.o Savanna

o Close to the equatoro A tropical grass lando Lots of vegetation but not many tall treeso They usually border a deserto Many animals grazingo Fire

Fire is an issue because there is so much dry grass. o Temperature

Usually hot in the day and cooler in the night. Since it is so hot in the afternoon, many of the animals there are nocturnal Many plants there must be able to store water. Also, they have small leaves and are short.

o Desertso We have a desert. The Mojavi.

o Grasslandso Our grasslands consist of Kansas, South Dakota, parts of Texas, Nebraska, Oklahoma, etc. o In these states, there are many farms and lots of wheat

"Bread Basket"o Animals there are usually large herbivores. o There are also occasional fires.

o Temperate Deciduous Forestso This means that there is a moderate temperature and trees loose their leaves in the fall.o This is our Biome (NY)

o Coniferous/Alpine Forests (Taiga)o Largest terrestrial biome o Long cold winterso Short wet summerso Conifers inhabiting them are adapted for that climateo Many of the animals there hibernate in the wintero Deforestation is an issue here too.

o Tundrao Low growing plants o Not many animals o Windy and cold

Causes a short growing seasono Animals here are usually carnivores. o Permafrost

Prevents root growth Not a lot of snow

o Types Arctic

Found in areas of Alaska and the Arctic circle Alpine

Found on mountain tops Biodiversity

o All the different living things on earth.o We get many things from it. o One group in the 1990's tried to see what would happen if you limited biodiversity.

o Each niche has a different purposeo These people made a bubble and went in it. They made sure that no oxygen could going or out.o They planned to stay a couple of years with no food or water brought.o They failed and had to leave after 15 months. o This shows that you need biodiversity.

o Threats to biodiversityo Habitat destructiono Introduced species

Zebra Mussels hitched onto a ship and came to America. It has no predators here and so it is overpopulating.

o Over-exploitation We over hunt and overuse them

o Food Chain disruptiono Extinction

o Small population leads to decreased variabilityo Decreased variability leads to a population that is less able to survive and reproduce.

Eventually you will end up with an extinction vortex (getting worse and worse)o Population gets smaller and the cycle continues

o Pollutiono Water

Chemicals are being dumped into the water and species can not live in that. Euthrophication Biological magnification

Plankton eats DDT and fish eats plankton and bird eats fish. This is why they say that eating deep sea fish can cause brain damage from mercury that accumulates.

Sewage Carries disease so they put chemicals on it then dump it into the ocean

Thermal pollution We are also making the water super hot.

Let's say that you own a factory and your machinery is getting very hot so you pour cold water on them to cool them down. Then you dump the boiling water in a nearby lake. This kills many fish and holds less oxygen which also kills fish.

Oil spills Exxon Valdez

A man ran a boat into Alaska and cause a HUGE oil spill causing lots of animals to die. o Radioactive pollution

It is bad because it can cause DNA mutations. o Noise Pollution

Loud sound waves can cause too many vibrations in the ear drum. Bats' major sense is hearing so if they become deaf from noise pollution, they can not survive.

o Air pollution .Sulfur and nitrogen come from factories and are released into the air.

This can cause acid rain Acid rain can cause rust on bridges and buildings that causes them to break. Also, it affects crops and produce It affects animals, especially water ones.

Hydrogen Sulfide smells like rotten eggs and is dangerous. Carbon Monoxide

Produced by burning gas, coal, and oil. CFC's

Chemicals that are released to make things come out of cans (like Lysol) They get up to the atmosphere and eat away at the ozone layer. The hole in the ozone is dangerous for crops, life forms, and causes skin cancer.

o Land Pollution If you throw garbage on the floor, it can contaminate water and the wild life gets into it. There are tons of pollution laws and the fines are extremely heavy for factory owners. (millions of

dollars) The government has to clean garbage before dumping it. *** REDUCE---> REUSE---> RECYCLE*** This can effect the soil and therefore cause plants to die off. Farmers rotate their crops to keep nutrients in the soil and not to keep land baron. They are

encouraged to put cover crops (like grass) on it. o Conservation

o Animal conservation There are tons of gaming laws.

You can not go and hunt at any time You can not hunt some animals You have to have a license There are many pieces of land where hunting is not allowed.

People are encouraged to limit uses of chemicals on land.o Forest conservation

For every tree lumberjacks cut down, they have to plant two trees. (reforestation) They limit tree cutting. Some areas are preserved.

o Alternative pest control methods You shouldn't kill bugs because many are carnivores (such as praying mantises and spiders) They can use natural predators. They can use bacteria and viruses to control larval growth of mosquitoes. Pheromones

A sex attracting chemical. It is what they put in ant traps There are larger species where this form of killing would be cruel and so farmers radiate the

males so they can not reproduce. The species will decrease