Ecosystems Flashcards
system
organised structure with interrelated parts
individual
a single organism
species
a group of organisms who 2 individuals can breed with each other
population
a group of individuals of same species that occupy area
ecosystem boundaries
can be water/topography
unclear boundaries
predators/vegetation/humidity/climate, some may be well bound with community (lake) others may not be (stream)
what can affect how well bound ecosystems are
climate change
ecotones
transition zones between ecosystems, can home species not adapted to climate change
species classifying order
taxon, taxonomic group, family, species, class
samples
when sampling you need to know species present/abundance/right time of year, need to take into account time/money of counting samples
quadrats
random/stratified (pre planned areas)/systematic (split into 20m areas), either percentage cover/number of individuals
quadrats bias
could be biased placing quadrats, might not be even, size of sample depends on ecosystem
releves
list of plants in an area, but needs knowledge of species
comprehensive inventories
long term monitoring, detailed but needs time/money
remote sensing
monitors lots of vegetation over time, only broad not species level
sampling techniques for animals
transects which record animals crossing it
how many species of plants/animals, new species found each year
350k plants, 1 mill animals, 300 new
species range
area where a species is found
which areas have small species range
islands as surrounded by water
how to measure biodiversity
species richness/abundance of species, shannon index/simpson index
2 categories of biodiversity
local (alpha), regional (gamma)
where is most biodiversity found
south america
why are species the way they are
extinction, immigration, speciation
niche
how a species lives not where, conditions that allow organism to live
n conditions
what the species needs (temp/rain)
niche model
3 dimensional, shows where species can be based on where it is now
competitive exclusion
if 2 competing species exist they do because of niche differentiation, realized niches must be different
what happens if theres no difference in differentiation
one species will eliminate the other
