- Wind the string around the wooden sticks so that you create a grid to study within your
ecosystem. - Make a list of all the plants and animals found in your ecosystem.
- Try and name the plants and animals. Use a reference book or the internet to identify
the plants and animals in your ecosystem. - Draw a distribution map showing where the different organisms were found in the
ecosystem. - Give each organism you found a code.
- Use the codes to make a map by showing where in the grid each organism was found.
- Record how many different plants and animals were found in your ecosystem.
- Which parts of your grid recorded the most plants and animals?
- Briefly discuss which abiotic factors influenced your ecosystem.
- Investigate what the animals in your ecosystem eat and then draw a food web for the
ecosystem. - Why do the organisms you found in your ecosystem live in this habitat?
- Write a short paragraph describing the ecological niche of one of the organisms you
observed.
Write a scientific report on the ecosystem you have studied.Your report should include the following:- A title
- Introduction
- Equipment or materials used.
- Results (including tables)
- Observations
- Discussion
- Conclusion
- References
- You can use drawings and photographs to illustrate your report.
9.6 Energy flow
Inecology, energy flow refers to the flow of energy through a food chain. In an ecosystem,
we attempt to establish the feeding relationships between organisms living together. Each
organism belongs to a ’trophic level’ which refers to the position occupied by an organism in
the food chain. Energy is passed on from every trophic level to the next and each time about
90% of the energy is lost with some being lost as heat into the environment and some being
incompletely digested food. So primary consumers get about 10% of the energy produced by
autotrophs while secondary consumers get 1% and tertiary consumers get 0,1%. A general
energy flow scenario is as follows:
- Autotrophs: solar energy is fixed by autotrophs such as green plants, using a process
known as photosynthesis into energy in the form of carbohydrates.
Chapter 9. Biospheres to ecosystems 277