Please enable JavaScript.
Coggle requires JavaScript to display documents.
Chapter 26 - Community Ecology (Community Ecology # (changes (habitat loss…
Chapter 26 - Community Ecology
Community Ecology
#
community = group of species at same time and place
climax community = before stability returns
community restoration = return to natural community
changes
habitat loss
succession = predictable changes
habitat fragmentation
Diversity
#
Diversity and Scale
checklist = species present
scale
larger areas = more diverse
smaller areas = less diverse
species-area relationship = area and species richness
measure diversity
alpha = local small site
beta = small sites within large region
gamma = species in a region
spatial scale
region = much less than continent
biome = large
local = small
biogeographical region = extremely large
species abundance distribution = plot species in each abundance class
Diversity and Latitude
high latitude s have low diversity
equatorial latitudes have more diversity
geographic and geological components
evolutionary history effects diversity
Predator - Prey Interactions
One Predator, One Prey
functional response = handling time and feeding rate
prey-dependent
predator's response depends on prey
more prey = faster feeding rate
one species attacks one prey
zero growth isocline = population stability
paradox of enrichment
predator overexploit prey
improve conditions of prey
both predator and prey are lost
maximum sustained yield
harvest just enough of a species
keep population density stable
fixed effort harvesting
goal is to retain species stability
how many of a species can be killed
fixed quota harvesting = hunters allowed to harvest a certain amount
Predator Selection Among Multiple Prey
optimal foraging theory
attack the prey
prey successfully eaten
prey individual will be encountered
optimal diet model
#
broaden diet if prey becomes scarce
some prey will always be eaten
predators prefer prey that provide most energy
plants eaten based on abundance
Competition Between Species
competition
exploitation =consume a shared resource
interference = one restricts another's access to prey
invasive = species increases even with a competitor near
resource = something that leads to increased growth
Apparent Competition = plant not competing for or using resource
Beneficial Interactions Between Species
nurse plants
one species alters rhe environment to help another
change small part of environment under them
primary succesion
organisms begin on newly created substrates
ex: volcanoes
interactions
#
mutualism
both benefit
ex: pollinators
facilitation
ex: beavers
one helps another with no benefit
Metapopulations in Patchy Environments
metapopulation
some patches are occupied; others are not
empty patches become colonized
environment has discrete patches
extinction possible in patches
different patches
source habitat = high quality
sink habitat = low quality
fugitive species
survives by colonizing new patches
ex: weeds
assisted dispersal
assisted migration
captured in one area and released in another area
Interconnectedness of Species: Food Chains and Food Webs
trophic levels
food web
numerous interrelationships
top carnivores + prey + plant species
energy flow web
how energy flows through the community
extremely difficult to produce
food chain
direct line of consumption
one predator and it's prey
keystone species = dramatically effect community
#
