Slide 1

Ecology Unit Option G1 G2 Selected Topics

Competitive Exclusion
No two species in a community can occupy the same niche

Fundamental vs. Realized Niche
Fundamental Niche: the potential mode of existence, given the adaptation of the speciesRealized Niche: the actual mode of existence, which results from its adaptations and competition with other species
Competition II
Competition I
Competition III
Realized Niche

Biomass
Total dry mass of organic matter of living organisms (measured in g m-2 yr-1)A table can be used to determine biomass of living organisms based on their weight (how do you suppose this is made?)Can be calculated for large areas by random selection of a sample ecosystem subdivisionSample plot can be measured thoroughly and a table can be used orSample plot organic matter could be collected, dried, and weighed

Primary Succession
Occurs when plants begin growing on previously lifeless areas. (i.e. volcanic island)Little to no soilLichens (decompose thin layers of rock)Pioneering plantsMossesSoil buildupLow productivity

Secondary Succession
New group of organisms takes over after a dramatic environmental change (forest fire, flood, etc)Soil already presentFaster processHigh productivity
http://www.offwell.free-online.co.uk/successn/primary2.htm

Organisms effect on the abiotic environment
Increase in organic matterSoil depthErosionSoil structureMineral recycling