23.1 Ecosystems Flashcards
Ecology
Study of relationships between organisms and their environment
Ecosystem
Living organisms and physical factors that interact with each other in an area
Biotic factors
The living factors
Abiotic factors
The non living factors
Examples of biotic factors
Interactions between living organisms
Usually competition for food, space and breeding partners
Examples of abiotic factors
Light Temperature Water availability O2 availability Edaphic (soil)
Light
Plants are affected by light availability - light is required for photosynthesis
Areas of low light - plants have larger leaves, photosynthetic pigments could require less light, or reproductive system only operates when light availability is at an optimum
Temperature
Warmer temperatures - greater ROR for enzymes controlling metabolic reactions
Plants and ectothermic animals will develop more quickly in warmer temperatures
What can changes in temperature cause for animals?
Migration
Hibernation
What can changes in temperature cause in plants?
Trigger leaf fall
Dormancy
Flowering
Water availability
Lack of water causes water stress and in severe cases, can cause death
In plants, can cause wilting, as water is required to keep cells turgid and plants upright
It is also required for photosynthesis
Oxygen availability
In aquatic ecosystems, it is beneficial to have fast flowing cold water - this contains high concentration of O2
Water that is too warm, or flow rate too slow can reduce oxygen concentration
In water logged soil, air spaces between soil particles are filled with water, so less oxygen is available for plants
Edaphic (soil) factors
Different soil types have different particle sizes, so different organisms can survive on them
Clay soil
Fine particles
Easily waterlogged
Forms clumps when wet
Sandy soil
Coarse well separated particles
Allow free draining
Doesn’t retain water and is easily eroded
