Ecology Unit 10- Chapters 18

Levels of Organization Old People Can’t Eat Beans Organism Population Community Ecosystem Biosphere Biotic components only All biotic and abiotic parts All life-13 miles thick, 5-6 of those above sea level. Begin chapter 18

Biotic and Abiotic Biotic Biosphere Ecosystem Community Population Organism Biotic and Abiotic Biotic

Organism to Community Organism- single living organism Population- single species living in the same place at the same time Community- a variety of species all living in the same place at the same time

Biotic vs. Abiotic Biotic includes Abiotic includes all living Once living-wood table, fallen leaves, etc. Potential for life- eggs, etc. Abiotic includes All non-living- air, temperature, water, rocks, sunlight, etc.

Tolerance curve Taken another way, how does food supply, size of habitat, etc. affect how well an organism survives? (hence the physical and chemical environment can affect the stability of a population)

Energy Transfer Producers-manufacture their own food through photosynthesis (green plants, some bacteria and protists) or chemosynthesis (hydrothermal vents at ocean bottom) Also called autotrophs Consumers Also called heterotrophs

Consumers These heterotrophs include: Herbivore- eat producers for energy Carnivore- eat other consumers for energy Omnivore- eat consumers or producers for energy Detritovores- feed on wastes (fallen leaves, dead organisms, animal waste) Decomposers- cause decay by breaking complex molecules into simpler molecules. Return nutrients to soil.

Energy Flow Digestion of food=metabolism=energy transfer. Example: if a snake eats a mouse, the snake gains vitamins and minerals that aid in the snake’s own energy availability to be able to pump blood, breath, move, etc. Where each organism lies within the sequence of these energy transfers (food chain) is its trophic level.

Energy pyramid Energy typically decreases by 90% between levels which explains why there is not enough energy for more than 3-5 trophic levels. 2 20 200 2000

Removing links What happens when you remove an organism from a food chain/web? It affects everything else above and below it. Example: If you remove the herbivore in level 2, level 1 will increase until it runs out of space, while level 3 and above will decrease because their food source has been eliminated.

Species relationships Commensalism-relationship between two organisms where one organism benefits but the other is unaffected. Mutualism-relationship between two species of organisms that benefits both species. Parasitism-relationship between two species of plants or animals in which one benefits at the expense of the other. Amensalism-relationship between two species that involves one impeding or restricting the success of the other while the other species has no effect on it. Symbiosis-close and often long-term interactions between different biological species. Examples include the for mentioned.

Water Cycle

Carbon Cycle

Nitrogen Cycle

Phosphorus Cycle

Population All the same species, living together in the same place at the same time. Population density- how crowded the population is. 1,000,000 people living in the US vs. same number living in Michigan vs. same number living in Shelby Twp. Begin chapter 19

Biodiversity helps maintain ecosystem sustainability. Disease Invaders Biodiversity helps maintain ecosystem sustainability. Farmer 2 (corn, wheat alfalfa) Corn disease appears Farmer loses only a portion of crop Farmer 1 (all corn) Corn disease appears Farmer loses whole crop

Succession The gradual, sequential (re)growth of a community. Example: Abandoned farm land Weeds perrenialssmall shrubsdeciduous forest large oaks The potential for life has to be present, there is no spontaneous appearance…no oak if the “seed” isn’t there or can’t be “brought in”. Begin chapter 20

Primary Succession Life where it never existed. Example: on a rock Lichen as a pioneer species- sometimes are composite organisms consisting of a symbiotic association of a fungus with a photosynthetic partner, usually either a green alga or cyanobacterium) rock weathering cracks Soil blows in mosses More soil Bigger plants Etc.

Secondary Succession Life after crisis Example: regrowth after forest fire…progression similar to abandoned farm field example. Once succession through the stages reaches a stable end point (still minor changes occuring) this is called the climax community.

Human impact on the environment Pollution Ozone depletion Global warming Acid rain Ecosystem disruption Deforestation Extinction Begin chapter 22