ecosystem
a community of biotic and abiotic components living with each other
producer
plants that begin food chain by making energy from CO2 and H2O
herbivore
also known as primary consumer- they eat plant matter
secondary consumer
a creature that eats herbivores
food chain
the connections between different organisms that rely upon one another as a source of food
food web
a complex hierarchy of plants and animals relying on each other for food
decomposer
- organism that breaks down dead tissue (e.g. bacteria or fungus)
- this effectively recycles their nutrients back to the environment in the form of humus
nutrient cycling
- a set of processes whereby organisms extract nutrients (e.g. nitrogen, potassium)
- necessary for growth from soil or water, before passing them on through the food chain - and ultimately back to the soil and water when they die
identify a small scale ecosystem and its components
- a freshwater pond
- biotic - tadpoles, water fleas, frogs, goldfish, heron
- abiotic - sunlight, water, oxygen, soil, temperature
what is the difference between a food chain and a food web?
- a food chain follows one path of energy and materials between species
- a food web is more complex and is a system of connected food chains
what factors can change the balance of an ecosystem?
natural factors: -drought -flooding -fire & disease human factors: -fish stocking -changing pH of water -altering the drainage of the land
explain the impact of changing one component of the ecosystem
- population numbers of producers and consumers may increase or decrease
- some ecosystems with fewer producers or primary consumers may collapse
biome
large scale ecosystems defined by abiotic and biotic factors
global distribution of the tropical rainforest biome
- found in tropical climates where warm air rises, and it is hot and wet all year round
- occurs between the tropics of cancer and capricorn
global distribution of the hot desert biome
found roughly 30 degrees north and south of the equator at sub-tropical belts where air sinks, preventing cloud formation
global distribution of the polar biome
- found where cold air sinks, mainly at the poles
- antarctica and greenland are the main polar regions
global distribution of the hot desert biome
found roughly 30 degrees north and south of the equator at sub-tropical belts where air sinks, preventing cloud formation
global distribution of the grassland biome
found roughly 40 degrees north of the equator - where conditions are dry for at least half the year, due to the movement of the hadley cell
global distribution of the temperature forest biome
- found mainly in the northern hemisphere north of the tropic of cancer and south of the arctic circle
- much of western europe (including the UK) and eastern china is covered by temperate forests
