Please enable JavaScript.
Coggle requires JavaScript to display documents.
Chapter 26: Community Ecology - Coggle Diagram
Chapter 26: Community Ecology
Diversity
Diversity and scale
Large area are more diverse than small area
Species area relationship: relationship between area and species richness
S= cA^z
Measuring diversity at specific scales
Alpha
number of species or growth forms that occur at local, small level
Beta
compares difference between several small sites within a larger region
Gamma
Number of species within a region
Species abundance distribution
Various level of Spatial Scale
Local
small area less than a few square km
Region
area larger than a few km
Biome
larger region characterized by dominant plants present, which turn are influenced by climate
biogeographical region
extremely large region
Diversity and latitude
Diversity varies with latitude
Equator have relatively benign environments whereas higher latitides have more severe conditions
High altitude = low diversity
Concept
Community
Group of species that occur together at the same time and place.
must have boundaries in both time and space
Sucession
more or less predictable sequence of change that occurs in many communites.
Climax community
Stable, self-aintaining community
remains same for many years
Community restoration
Process of assisting of an community that has been degraded, damaged or destroyed.
Habitat fragmentation
cause by farm, mine, buildings and etc
Predator-prey interaction
competition between species
Exploitation competition: occurs when organism consume a shared resources.
Inteference competition: one organism restrict the another organism's access to resources even though first might not be using it.
Perdator selection among multiple prey
Communities have multiple plant species that are prey to herbivorus predators .
iptimal foraging theory: help to predict how an aminla behave when searching for food.
Optimal diet model: foragers should ignore low profitability prey items when more protiftible items are present.
Apparent competition
Indirectly competing with another species where both of them serve as prey of a predator.
one predator, one prey
plants are attacked by herbivore
Feeding rate: how quickly a predator find a new prey individual, and handling time refers to the amount of time neede to actually consume the prey.
Functional response: number of prey successfully attacked per predator as a function of prey density.
dN/dt= rN- aNP
zero growth isocline: line indicating population stability
Fixed effort harvesting: population health is determined by the amount of fish or deer etc, that can be hervested with a particular amount of effort or time
Fixed quota harvesting: fisherman or hunter are allowed to harvest a particular amount such as one deer per hunter no matter how long it takes or how much effort it required.
Beneficial interaction between species:
mutualism: both organisms benefit. Eg: pollinator and the plants they pollinate
Facilitation: one organism help another without receiving any benefits.
Primary succession: organisms become established on newly created substrate.
Metapopulations in patchy environment
Several local population are interconnected by migration and gene flow between the patches.
source habitat: high-quality patches
sink habitat: low- quality patches
Fugitive species: one that survive by colonizing new patches, flourising temporarily and then colonizing more patches before it dies out in old one.
food chain and food web
Food web: one path of energy as animal find food.
food web: shows how plants and animals re connected in many ways to help them all survive.
Keystone species: presence or absence of certain species
Assumption of metapopulatin:
Aregion of the environment is composed of many discrete patches in which the species can live
some patches are occupied by species, other suitable patches are not.
empty patches will become colonized by migration from occupied patches.
population within individual patches have a probibility of going extinct within that patches
