6.5.1 Ecosystems Flashcards
What are ecosystems?
Species do not exist by themselves in their own isolated environment, they interact with other species forming communities
These communities interact with each other and the environment they live in, forming ecosystems
An ecosystem is a relatively self-contained community of interacting organisms and the environment they live in, and interact with
There is a flow of energy within an ecosystem and nutrients within it are recycled
There are both living (biotic) components and non-living (abiotic) components within an ecosystem
What do ecosystems vary in?
Ecosystems vary greatly in size and scale
Both a small pond in a back garden and the open ocean could be described as ecosystems
An individual human being could also be described as an ecosystem; there are thousands of species of bacteria living on and in every person
Ecosystems vary in complexity:
A desert is a relatively simple ecosystem
A tropical rainforest is a very complex ecosystem
No ecosystem is completely self-contained as organisms from one ecosystem are often linked to organisms from another
For example, birds are able to fly long distances to feed from multiple ecosystems
What is an example of an ecosystem?
A forest is a perfect example of a complex ecosystem
There is a large community of organisms including trees, birds, small and large mammals, insects, bacteria, and fungi
The non-living components of the ecosystem include the soil, dead leaves, water from the rain and streams, the rocks, and any other physical or chemical factors
The non-living components of the ecosystem influence the community of organisms
What are biotic factors?
A biotic factor is anything that influences the populations within a community that is a result of another organism’s activity
What are examples of biotic factors?
Predation
Competition (inter-specific) for space, food, water, light etc.
Cooperation between organisms (can be between the same species or different species)
Parasitism
Disease
Pathogenic disease caused by microorganisms e.g. cholera, or carried by vectors e.g. malaria
Camouflage
A well-camouflaged prey animal will escape capture and not benefit the potential predator species
Mimicry
A hoverfly is harmless, yet it has evolved body colouring like that of a wasp. This deters potential predators into thinking that it is a wasp and could deliver a harmful sting
Mankind
Arguably the largest biotic factor of all, in terms of habitat loss, hunting, farming etc
What are abiotic factors?
An abiotic factor is any physical or chemical factor (non-living) that influences the populations within a community
The environmental conditions can majorly impact the spread of a species
What are examples of abiotic factors?
Availability of water
Light
Radiation
Temperature
Turbidity (‘cloudiness’) of water
Humidity
Atmospheric composition
pH
Salinity
Soil composition
