Topic 10: Ecosystems Flashcards
Define habitat
where an organism lives
define community
all the populations of all the different species in a habitat
define niche
the role of an organism in the community
define abiotic factors
non living elements of the habitat
define biotic factors
living elements of the habitat
define ecosystem
the environment including all the living organisms interacting within it, the cycling of nutrients and the chemical and physical environment
define succession
the process by which communities of organisms colonising an area over time change
explain the process of primary succession
empty inorganic surface colonised by pioneer species - mosses and fungi break down the surface - form hummus environment made less hostile other plants colonise plant + animal diversity increases pioneer species outcompeted climax community
define climax community
self-sustaining community
constant biodiversity
no further succession
what is the difference between primary and secondary succession?
when the starting point is empty inorganic surface its primary
when its bare soil its secondary succession
name abiotic factors which may affect populations?
light, temperature, wind and water, water availability, oxygen availability, edaphic factors
how does light intensity affect populations?
plants need light for photosynthesis
animals feed on plants
plants are habitats for animals too
how does temperature affect populations?
enzyme-controlled reactions such as respiration and photosynthesis are controlled by temperature
define population
group of organisms of the same species that breed together
what affects water availability?
precipitatio,
rate of evaporation
loss by drainage
