Complete the chart by filling in the effects of each positive action
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Question 2
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Nice
California's dry climate and infrequent rainfalls have caused its population to seek solutions for their waste problems. One solution was to build dams. Reservoirs created by the dams could be used to store water until needed. The water could then be used in homes, irrigation, and industry. But, building dams is controversial. There are many aspects that can be impacted by the building of a dam. Dams destroy the natural environment, prevent erosion, and keep species from their natural habitats.
Changing Hetch Hetchy
In Northern California, the O'Shaughnessy Dam is the subject of much debate. It was built in the Hetch Hetchy Valley of Yosemite National Park. Some claim the dam should never have been built because a national park is a protected place. Others think the dam is valuable because it supplies the city of San Francisco with 25 percent of its drinking water.
Proponents of restoring Hetch Hetcy Valley to its original state are asking the the water from the reservoir be stored in other reservoirs. The dam also supplies water to three hydroelectric power plants. Removing the dam would reduce the power supply by 20 percent. Hetch Hetchy's supporters think the city's power needs could be met in other ways.
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Question 5
5.
What is one strategy California uses to save water mentioned in the passage? __________
How do dams harm nature? __________
What is the name of the dam in Hetch Hetchy valley? __________
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Question 6
6.
Drag the use of water to the appropriate area of use
Spray irrigation
Drip irrigation
Kitchen sink
Laundry Matt
Paint manufacturing
Home
Irrigation
Industry
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Suffocating Sediment
The Rindge Dam is located in Malibu, California. The dam was built in the early 1900s to meet Malibu's water and power needs. Within 20 years, almost 13m of sediment had built up behind the dam as a result of the interruption of the erosion process. The Rindge Dam also traps endangered fish species - the steelhead trout - in a small area.
The Rindge Dam stopped being useful by the late 1940s. As the dam ages, it becomes more vulnerable to earthquakes. California is working with the federal government to raise funds to remove Rindge Dam.
Removal Results
Could the Hetch Hetchy Valley be restored to its original splendor? Would the removal of Rindge Dam allow steelhead trout to reach the ocean? Supporters describe the results of removing a dam in Washington.
Water in the Elwa River flows from the Olympic Mountains down into the Strait of Jaun de Fuca. A dam prevented salmon and sediment from reaching the Strait. The dam was removed in 2011-2012. Salmon were able to reach their spawning grounds. Sediment reached the mouth of the Elwah River and poured into the Strait of Juan de Fuca. Riverbanks were restored and an estuary for crabs, clams, and other species was created.
Nitrogen is an element that cycles naturally through ecosystems. Living things use nitrogen to make proteins. When these living things die and decompose or produce waste, they release nitrogen into the soil or the atmosphere. Scientists estimate that human activities have doubled the amount of nitrogen cycling through ecosystems.
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Question 10
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What do living things use nitrogen to make? __________
What actions release nitrogen into the atmosphere? __________
Scientists estimate that human activities have __________ the amount of nitrogen cycling through ecosystems.
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Question 12
12.
How does the use of fertilizers affect the environment?