Term
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Definition
| -an assemblage of plant and animal populations that interact and influence one another |
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Term
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Definition
-type of community structure
-physical strucuture |
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Term
| species composition structure |
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Definition
-type of community structure
-diversity |
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Term
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Definition
-type of community structure
-energy transfer (heterotrophic, autotrophic) and functional groups |
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Term
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Definition
-type of community structure
-seasonal or diurnal (day) activity |
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Term
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Definition
-ex. of plant physical structure
-life forms that are based on over wintering bud or growth form and leaf characteristics |
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Term
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Definition
| -Carry their buds on the tips of branches, exposed to the extremes of climate. (Most trees and large shrubs) -dominate in warm moist environments. # 1a on figure |
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Term
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Definition
-Small shrubs and herbs that grow close to the ground (prostrate life from). -Proximity to soil protects the bud, and in winter, snow
-Cover provides additional protection from extreme cold.
-Frequently occur in cool dry climates. #’s 2 + 3a on figure |
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Term
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Definition
-The surviving buds are situated in the soil surface.
-Buds are protected by soil or leaf litter.
-Frequently occur in cool moist climates.
# 4a on figure |
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Term
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Definition
–Buds are protected from extreme weather because they are completely buried beneath the soil.
-Frequently occur in cool moist climates.
(also called geophytes) #’s 5-9a on figure |
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Term
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Definition
-are annuals
-are semelparous
-found in deserts and grasslands |
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Term
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Definition
-the term for a group of organims that make their living (feeding) in a similar way
-commonly used by animal ecologists |
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Term
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Definition
| the number of species and their relative abundance |
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Term
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Definition
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Term
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Definition
| -the relative abundance of species |
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Term
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Definition
-term used by botanists
-is the combination of its structure and growth dynamics |
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Term
Shannon-Weiner index
[image] |
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Definition
| - a commonly applied measure of species diversity |
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Term
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Definition
-the value of the Shannon-Weiner diversity index
-value ranges b/t 0 and 4
-as this value increases, species diversity increases |
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Term
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Definition
-shows the relative abundance and diversity of species within a community by plotting the relative abundance of species against their rank in abundance
-greater evenness is indicated by lower slope |
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Term
| factors affecting diversity |
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Definition
-climatic stability
-resource division
-predation
-disturbance
-productivity |
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Term
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Definition
-a relatively discrete event in time coming from the outside that disrupts ecosystems, communities, or populations
-changes substrates and resource availability
-creates opportunities for new individuals or populations to become established |
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Term
| disturbance characteristics |
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Definition
-size
-frequency(# events per unit time)
-turnover (time b/t disturbances)
-intensity (physical force of the event)
-severity (impact on the biota) |
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Term
| intermediate disturbing hypothesis |
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Definition
developed by Joseph H. Connell
-hypothesis that states the highest species diversity at intermediate levels of disturbance |
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Term
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Definition
-enhanced growth, fitness, survivorship, etc. due to environmental modifications by other species
-aka nucleation |
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Term
| index of biological integrity |
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Definition
-determines the health of aquatic ecosystems
-12=very poor quality 60=very high quality |
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Term
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Definition
| -species that have high influence on community structure, but have low biomass |
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Term
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Definition
| -a position in a food web and is determined by the number of transfers of energy from primary producers to that level. |
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Term
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Definition
| -the transfer of energy from one part of an ecosystem to another |
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Term
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Definition
| the incorporation of any material into tissues, cells of an organism |
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Term
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Definition
Energy assimilated X 100
energy ingested |
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Term
| Community b has greater species diversity because it has greater species evenness |
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Definition
| Communities a and b both contain five tree species. Community b has greater species evenness. Community a is dominated by one of its five species. which one has higher species diversity |
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Term
| effect of predation on species diversity |
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Definition
| Predation increases diversity |
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Term
| high levels of disturbance |
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Definition
| disturbance that reduces diversity |
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Term
| low levels of disturbance |
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Definition
| level of disturbance that allow competition to reduce diversity |
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Term
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Definition
| disurbance level where there is sufficient time between disturbance for a wide variety of species to colonize but not enough time to allow competitive exclusion |
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Term
| disturbance and diversity in the intertidal zone |
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Definition
supported intermediate disturbance hypothesis
species of marine algae and invertebrates on intertitdal boulders had the highest species diversity on boulders that expperienced intermediate levels of disturbance |
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Term
| disturbance by prairie dogs and plant species diversity |
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Definition
supports the intermediate level of disturbance hypothesis
plant species diversity is highest at intermediate levels of disturbance which allows a high diversity of both grass and forb species |
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Term
| disturbance generalizations |
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Definition
-disturbance affects community equilibrium and therefore species diversity
-disturbance is harmful to the individual and may be detrimental to the pop. or species but often it is beneficial from the standpoint of maintaing or enhancing species diversity |
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Term
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Definition
| a desert shrub modified its environment by lowering the temp. of the air, soil, etc around it |
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Term
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Definition
| an example of a keystone species that is not an apex predator |
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Term
| a mutalistic keystone species |
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Definition
reef cleaning fish
there is high diversity in corals because of these fish cleaning out parasites of other fishes, therefore attracting more fish |
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Term
| james river apex predator |
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Definition
| catfish were introduced into the James River and have detrimented the American shad population numbers and the catfish have severely simplified the food web |
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Term
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Definition
| a lake where over 400 different species of fish lived and when the nile perch was introduced (apex predator) they destroyed the complex food web and now there is only about 3 different species of fish |
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Term
| Channa argus (snake head) |
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Definition
- an introduced apex predator in the Chesapeake Bay
-eats everything |
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Term
| assumptions of energy flow through an ecosystem |
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Definition
-50% of energy used for a heat tax for respiration
-10% of energy passed on to next trophic level
-40% incorporated as biomass which eventually goes to decomposers |
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Term
| net primary production (NPP) |
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Definition
-production that is measured as the energy stored or biomass (dry weight)
added by producers per unit area OVER A GIVEN TIME SPAN |
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Term
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Definition
| -occupy the first trophic level in ecosystems since they use inorganic forms of energy (light) to convert CO2 into biomass |
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Term
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Definition
-herbivores and detritivores that occupy the second trophic level
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Term
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Definition
| -carnivores feeding on herbivores and detritivores that occupy the third trophic level |
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Term
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Definition
-group that feeds on on carnivores
-occupies the fourth trophic level |
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