[问答题]
1. A student had a small
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She wanted to first determine whether Fish A or Fish B would be more suitable, or if both fish could be added to the pond. As a trial, she set up four mesocosms using water from the pond. She monitored the mesocosms and then added the fish to three of the mesocosms as shown. She took samples of water from the different mesocosms and tested it for chlorophyll content at a research lab nearby.
1.Outline why the mesocosms used would be considered a ‘closed system’.
2.Describe why adding mud or soil to the mesocosms would be advantageous.
3.Outline the reason for including ‘Mesocosm A’ with the experiment.
4.Explain the reason for monitoring chlorophyll content to analyze the effects of the fish as a predator.
5.State another variable that could be monitored to see the effect of adding fish to the mesocosms.
The following table shows the results obtained for chlorophyll (μg dm$^{-3}$) with the different additions of fish.
6.From the results obtained, suggest why the student decided to add both fish A and fish B to the pond.
