Summary
An ecosystem is a functional system in which organisms interact with one another and with abiotic surroundings.
Core concept
Understand the system
An ecosystem is a functional system in which organisms interact with one another and with abiotic surroundings.
Why / how it happens
Causes and context
An ecosystem is a functional system in which organisms interact with one another and with abiotic surroundings. The governing relationship is: Energy flows mainly from sunlight through trophic levels, while nutrients cycle between biotic and abiotic components.
Mechanism / process
Energy flows mainly from sunlight through trophic levels, while nutrients cycle between biotic and abiotic components.
Key facts
- Producers capture energy; consumers transfer it; decomposers recycle matter.
- Food webs are more realistic than single food chains.
- Ecosystem boundaries can be open and defined at different scales.
Important terminology
- biotic
- abiotic
- trophic level
- food web
- decomposer
Named examples / case studies
- A mangrove ecosystem links salinity, sediment, plants, fish, microbes and human livelihoods.
Causes / components
- Key components: biotic, abiotic, trophic level.
- Energy flows mainly from sunlight through trophic levels, while nutrients cycle between biotic and abiotic components.
Effects / significance
- Food webs are more realistic than single food chains.
- Ecosystem boundaries can be open and defined at different scales.
- Application: A mangrove ecosystem links salinity, sediment, plants, fish, microbes and human livelihoods.
Geography connection
A mangrove ecosystem links salinity, sediment, plants, fish, microbes and human livelihoods. This illustrates how ecosystem varies by location, scale or environmental context.
Bangladesh connection
The Sundarbans, haor wetlands, floodplains and coastal estuaries are major Bangladesh ecosystem examples.
BCS preliminary facts
- Producers capture energy; consumers transfer it; decomposers recycle matter.
- Food webs are more realistic than single food chains.
- Ecosystem boundaries can be open and defined at different scales.
BCS written analysis
Build an analytical answer
- An ecosystem is a functional system in which organisms interact with one another and with abiotic surroundings.
- Energy flows mainly from sunlight through trophic levels, while nutrients cycle between biotic and abiotic components. Use a mangrove ecosystem links salinity, sediment, plants, fish, microbes and human livelihoods. as a named application in a comparative answer.
Common misconceptions
- Energy flows one way while nutrients cycle.
- An ecosystem is not only its organisms; abiotic conditions are essential.
BCS PRACTICE ENGINE
Test Your Knowledge
Select the best answer, then check your response.
Ecosystem: which statement correctly applies biotic to this topic?
Quick revision
- Ecosystem
- Producers capture energy; consumers transfer it; decomposers recycle matter.
- Food webs are more realistic than single food chains.
- biotic / abiotic
- Definition → process → spatial example