Interdependence of Ecosystems~ everything's prosperity depends on everything around it. "No man is an island, entire of itself; every man is a piece of the continent, a part of the main"- John Donne

Sustainability~ the ability to meet the needs of the present generation without compromising the ability of future generations.

Ecosystem~ all organisms in an area that interact with each other and with the environment of energy and non-living things.

Energy (from the sun)~ the "fuel" of any ecosystem. It is captured by plants for photosynthesis and stored as chemical energy in carbohydrates. The energy passes through the ecosystem from organism to organism forming a 'food chain'.

Food Chain~ a series of organisms that can pass on energy in the ecosystem

<---Food Web~ interconnected food chains.

Herbivore~ an organism that consumes only plant material.

Carnivore~ an animal that only eats meat.

Detrivore~ organism that eats dead material and animal waste.

Omnivore~ an animal that eats meat or plants.

Abiotic~ nonliving part of the environment.(hint: a=non)

Biotic~ living part of the environment.

Decomposer~ various bacteria and fungi that breakdown dead material and animal waste and extract the remaining nutrients.

Habitat~ a place where an organism lives.

Biodiversity~ the variety of living organisms.

Trophic Level~ feeding level of one or more organisms in a food web.

Pyramid of numbers~ shows the relative population sizes of organisms at each link in a food chain. The first tropic level (grass) gets the most amount of energy from the sun. As the energy goes to the next trophic levels (mice, snakes) more organisms need to be added together to get the amount of energy needed for the larger organism (hawk). So there are usually more organisms in the bottom trophic level (making a pyramid!) There are many exceptions to the pattern; millions of insects feeding off of only a couple trees.

Pyramid of Biomass~ combines number and weight of organisms ie: Biomass (total dry mass of a population). This could mean alot of small organisms or few larger ones. Biomass decreases from each trophic level. There are few exceptions; algae grows much faster than zooplankton therefore producing enough energy to support a larger population of zooplankton.

Pyramid of Energy (flow)~ measuring the total chemical energy that flows through each trophic level. It eliminates exceptions because there is always less energy available for the next trophic level in the pyramid.

Population~ all the individuals of *of one species* that occupy a certain geographical area during a certain time. Constantly changing because of death, immigration, emmigration, and births.

Carrying Capacity~ maximum number of organisms in a populationthat can survive on the resiources available in an ecosystem. There are four limiting factors: ¹Resources Available: sun energy, food, water, shelter. ²Position in food chain: population size limited by size of level below and above it. ³Competition: demand for resources by other organisms. 4.Density: different animals have different needs for space which determines the population.

Density Dependent Factors~ factors that increase in significance as the population grows. Ex: overcrowding would increase spread of diseases.

Density Independent Factors~ factors that can limit a population regardless of its size. Ex: forest fires, floods.

IntERspecific Competition~ when two organisms of DIFFERENT species are after the same resource or food.

 IntRAspecific Competition~ when two organisms of the SAME species are after the same resource of food.

Monoculture~ opposite of biodiversity. All the same organism in one area. Not usually natural. Ex: Wheat Farm

Pest Populations~ Insects that feed on one type of food so they increase as we grow one type of food. Pesticides are used to control the pest population.

DDT~ a type of pesticide that remains in the environment for long periods of time which affects food chains. Biological Magnification~ the seawater has a small amount of DDT in it, the plankton use the water, the squid eat the plankton, the dolphins eat the squid and have a large amount of DDT passed through the chain. (basically the DDT accumulates into larger amounts as it goes up the food chain) Mostly larger animals are affected by DDT because they have the most in them from eating so many organisms with DDT in them also.

Nutrient Cycles

Carbon Cycle~ carbon comes in as C02, the producers convert it to carbohydrates, animals eat plants (carbs) and convert that into carbon dioxide (breath out).                                  Formula: Photosyntheis-CO2> C6 H12 O6                     Cellular Respiration-C6 H12 O6> CO2

For more complicated one involving p and s consumers see text.

Nitrogen Cycle~ Nitrogen in atmosphere is pulled out and bonded to other elements to make a usable form of nitrogen called ammonia(NH4+). Nitrifyin Bacteria turns the ammonia into nitrates(NO3-) which plants absorb with roots, the animals eat the plants, 2nd trophic level also. The plants and animals decompose (dead and waste). Decomposers make waste into nitrifying bacteria which can be absorbed by the plants roots again or turned over denitrifying bacteria. The denitrifying bacteria takes nitrogen out of soil and returns it to atmosphere.

Eutrophication~ when too much nitrogen builds up in lakes and ponds.

Fertilizers~ mixtures of elements that can help enrich soil.

Primary Succession~ When a bare landscape begins a process to transform into a suitable environment for organisms to live it. 5 stages.

Climax Community~ a community that has the most amount of organisms it can support in that area.

Secondary Succession~ after a disturbance the ecosystem will restore (remediate) itself to a climax community.

Phytoremediation~ plants that help to remove toxic materials in the soil by using them as part of their tissue (part of plant).

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