The red squirrel is a species of tree squirrel that can be found in parts of Europe and Asia. In an experiment, a researcher introduced two small, essentially identical populations of red squirrels into two different environments at the same time. The researcher measured a number of characteristics of each ecosystem and summarized his findings in the table below. What limiting factors would have a greater effect on the city park population than on the nature reserve population?
Food
Trees for Shelter
Rainwater
Predation
Runoff from an industrial chemical plant is released into the surrounding marshland. The plants in the marshland absorb the polluted water through their roots. Which of the following is the most likely to occur over time?
The concentration of the pollutant will increase in plant populations, but animal populations that eat the plants will be unaffected.
Plants and animals in the ecosystem will quickly filter out the pollutant without any long-term impact.
There will be an increase in the concentration of the pollutant in any animal populations that feed on the plants.
Plants and animals in the ecosystem will excrete the pollutant faster than they take it in, so the pollutant will not build up in their tissues.
