Biodiversity Measuring Biodiversity - Mrs. Gamzon's...
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Measuring Biodiversity • The Earth is contains a tremendous number of life forms. • There are different ways to quantify how biodiverse an ecosystem is. Biodiversity Species Richness: The number of species in a given area. Species Evenness: The measure of whether a particular ecosystem is numerically dominated by one species or are all represented by similar numbers of individuals. Biodiversity High Evenness Low Evenness Identical Richness Measuring Biodiversity • Shannon Index • Increases as both the richness and the evenness of a community increase. • Makes it difficult to compare communities that differ greatly in richness. Pi = ni/N ni = number of individuals in a given species N = total number of individuals in the community The higher the number the more biodiverse! Measuring Biodiversity • Simpson’s Index • This index is used to measure the dominance of a community, which is the opposite of evenness. • As D increases, the diversity decreases. Pi = ni/N ni = number of individuals in a given species N = total number of individuals in the community Values are between 0 and 1 with 1 being a monoculture.
Transcript of Biodiversity Measuring Biodiversity - Mrs. Gamzon's...
Measuring Biodiversity
• The Earth is contains a tremendous number of life forms. • There are different ways to quantify how biodiverse
an ecosystem is.
Biodiversity
Species Richness: The number of species in a given area.
Species Evenness: The measure of whether a particular ecosystem is numerically dominated by one species or are all represented by similar numbers of individuals.
Biodiversity
High Evenness Low Evenness
Identical Richness
Measuring Biodiversity
• Shannon Index • Increases as both the richness and the evenness of a
community increase. • Makes it difficult to compare communities that differ
greatly in richness.
Pi = ni/Nni = number of individuals in a given speciesN = total number of individuals in the community
The higher the number the more biodiverse!
Measuring Biodiversity
• Simpson’s Index • This index is used to measure the dominance of a
community, which is the opposite of evenness. • As D increases, the diversity decreases.
Pi = ni/Nni = number of individuals in a given speciesN = total number of individuals in the community
Values are between 0 and 1 with 1 being a monoculture.
