Biodiversity Flashcards
definition: Biodiversity
number and variety of species in a particular area
extreme environment
less biodiversity= unstable ecosystem=dominated by abiotic factors (temp, wind, soil type)
less hostile environments
more biodiversity= stable ecosystem= biotic factors (disease, competition, predation)
succession
-gradual change in composition of a community over time
-pioneer species -> first to colonise ( bare sand) -> survive hostile environments
Does this by (adding moisture, more stable and more nutrients)
-other species can then colonise
diversity of plant species increase
human influence
human activity= less hospitable environment
(deforestation, climate change, over-fishing, pollution)
fossil record-> most species extinct
extinction=
change in climate/habitat, increased competition, new predators
extinction= natural process
species richness and eveness
species richness
-number of species found in a habitat
species eveness
-measure of abundance of individuals in each species
low species diversity
- few well adapted species
- simple food webs
- change in environment have serious effects
high species diversity
- more stable ecosystem
- less hostile (more ecological niches)
- complex food webs
- change less damaging to the system