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Supplemental Videos

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Ecological Terms

Investigating Numbers and Distribution

Investigating Variation

Frame Quadrats

Line Transects

Mark-Release-Recapture

Diversity

Abiotic (non-living) Factors

Biotic (living) Factors - Interaction Between Organisms

Table 5-14-1: The environment influences diversity


Less Extreme/Harsh Environments

Extreme Environments

Higher diversity → more plant species → more niches→ greater variety of food → less competition for resources → more food available → less harsh environment (abiotic) in forest

Lower diversity → less plant species → less
niches → smaller variety of food → higher competition for resources →less food available → more harsh environment (abiotic) in forest

Stable ecosystem, if the population of one species changes, alternative food sources are available

Unstable ecosystem, change in the population of one species affects populations of other species

Biotic factor(s) dominate

Abiotic factor(s) are extreme and dominate

Many species have adaptations that allow them tosurvive, including many producers

Only a few species have adaptations that allow them to survive

Higher solar energy input gives more light for photosynthesis (and higher temperatures)

 

Succession

Table 5-14-2: Succession


PIONEER COMMUNITY

STABLE CLIMAX COMMUNITY

HARSH ENVIRONMENT

LESS HARSH ENVIRONMENT

PIONEER SPECIES WITH ADAPTED CONDITIONS

MORE PLANT SPECIES CAN GROW

LOW DIVERSITY

HIGH DIVERSITY