23.1 ecosystems Flashcards
1
Q
define ecosystem
A
an ecosystem is made up of living organisms that interact with one another in a define area and the physical factors that are present in that region
2
Q
what are the biotic factors
A
- interactions between living organisms
- usually involve competition for things such as food, space and breeding partners
3
Q
what are the abiotic factors (5)
A
- light
- temperature
- water availability
- oxygen availability
- edaphic factors
4
Q
effect of light
A
- greater the light availability, the greater the success of a plant species
- plants adapt to cope with different intensities
5
Q
effect of temperature
A
- effects enzymes controlling metabolic reactions
- plants/endothermic animals develop rapidly in warm temperatures
- in animals : trigger migration or hibernation
- in plants : can trigger leaf-fall, dormancy and flowering
6
Q
effect of water availability
A
- lack of water = stress = death if severe
- in plants : causes wilting as water is needed for photosynthesis and keeps cells turgid/upright
- xerophytes are adapted to cope with water stress
7
Q
effect of oxygen availability
A
- aquatic ecosystems : fast-flowing cold water with high oxygen concentrations
- waterlogged soil : air spaces between soil are filled with water which reduces oxygen available to plants
8
Q
effect of edaphic factors
A
- clay : fine particles, easily waterlogged and clumps when wet
- loam : different-sized particles, retains water, doesn’t become waterlogged
- sandy : coarse, well-separated particles allowing free draining, doesn’t retain water, easily eroded
