The diagram shows the watershed around an underground mine. Stream 3 runs from the top of the mountain ridge to the lake. The entire watershed is underlain by bedrock that contains some metal. A town on the lake shore is concerned because of an increase in metal contaminants in the lake.

(a) Based on the diagram, describe how human activities could have increased the amount of metal contaminants in stream 3

(b) Based on the diagram, explain why stream 2 would have a higher temperature than stream 1.

(c) Based on the diagram, make a claim using evidence that a supporting ecosystem service has been devalued as a result of human activities.

(d) Based on the diagram and in terms of the water cycle, describe how the hydrologic cycle would cause the lake to have a higher concentration of metal contaminants than any of the streams.

(e) Soil compositions can vary based on location. Explain why soils located near clear-out forests might differ from soils located near intact forests.

(f) Some of the miners assert that the area in which the ore is being mined must have been located at a transform plate boundary. Make a claim using evidence that supports or opposes the miners' assertion.

(g) The mining company claims that they cannot extract enough ore from the mine and wants permission to convert the mine into a strip mine. Describe why converting the mine into a strip mine may not be the best choice residents of the town who are concerned about metal pollution in the lake.

Scientists are interested in investigating the possibility that plants can be used to remove heavy metals from contaminated soil. They divide a sample of soil with heavy metal contamination into five different pots and plant five different species of grass they believe will take up metals into their roots and leaves. They also plant the same grasses in five pots with uncontaminated soil. After allowing the grasses to grow for a month, they out the grass and measure the concentration of metals in milligrams per kilogram.

(h) Identify the dependent variable for the investigation.

(i) Identify one modification that could be made to the investigation that will alter the results.

(j) After determining the species of grass that removes the most metal, it is planted in the area that was logged. In addition to removing metals from the soil, describe one advantage to stream 3 of planting grass in this area.