L13 Flashcards
Biodiversity
The genetic, species, and ecological richness of the organisms in a given area
species richness
count of how many species are present in a defined area
species diversity
measure that incorporates both species richness and evenness
what happens to communities that aren’t evenly distributed?
dominance, rarity
shannon diversity index
represents degree of heterogeneity in a community
(shannon) high value of H
high species diversity
(shannon) low value of H
low species diversity
“stressed” rank abundance curve
steep slope, high initial value
“stable” rank abundance curve
gradual slope and lower initial start
detritus
all forms of nonliving organic matter
Categories of detritus
CPOM, FPOM, DOM
detritivores
primarily insects, crustaceans that feed on detritus
decomposers
organisms that use dead organic matter as an energy source (fungi, bacteria)
Process of detrification:
- Microbes colonize
- produce FPOM
- Invertebrates come and consume FPOM
- Shredders feed directly on leaves (PB)
- Predators eat
High “N” leaves
fast decomposition