Integrated Science: Ecology & Ecosystem

II. Ecology – “oikos” Greek word meaning house; branch of science that deals with the interaction of organisms with each other and their environment

A. Organism – anything that has life (grows, needs nutrients, reproduces, can move, made of cells, respond to stimuli); classified as species or groups of organisms that resemble one another in appearance, behavior, genes and chemistry; they reproduce under natural condition sexually or asexually

B. Niche – organism’s or population’s way of life and its use of environment; includes habitat or place where it lives, what nutrients it needs or what eats them, its role in the population or environment and other needs like space, rest, light, temperature, moisture, air

C. Population – all members of same species at a given area and at a given time; changes in size, density, distribution; measure in size, density and distribution

D. Community – different populations in an area interacting with each other.

III. Ecosystem – provides resources; composed of communities, population and organisms; union of biotic and abiotic factors in an area; interacting communities with biotic and abiotic factors; size is as big or as small as anything with organisms interacting with each other and other biotic and abiotic factors

A. Biotic Factors – produces, consumers, decomposers, living factors
2. Producers – produce or make their own food; autotrophs/self feeder; land ecosystems: green plants; aquatic ecosystems: bacteria, planktons, protests; uses sunlight for energy (photosynthesis); chemosynthesis is the use of radioactive elements
3. Consumers – feed on other organisms; heterotrophs/other feeder
a. Herbivore – feed on plants; primary consumer
b. Carnivore – feed on meat or other consumers; secondary/tertiary consumer
c. Omnivores – feed on both plants and animals
d. Scavengers – feed on dead organisms healed by other or died naturally
4. Decomposers – breaks down dead organic materials (detritus) to get nutrients and release into inorganic materials
a. Detritivores – feed on detritus; partly decayed organic materials and waste of living things; detritus feeder
B. Abiotic factors – physical or chemical factors
1. Physical – sunlight and shade, average temperature and range, fire, average precipitation and timing, wind, latitude and altitude, soil nature, water current and amount of suspended materials in an aquatic ecosystem
2. Chemical – water and air supply in soil, plant nutrients dissolved in soil moisture and in aquatic habitat, salinity, level of dissolved aquatic oxygen

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