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The Dust Bowl 1

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The Dust Bowl 1 ECHOLS MIDDLE SCHOOL CONTINUITY ASSIGNMENT ACADEMIC HELP LINE: Open Monday-Thursday from 8:30-11:30 WEEK: May 18-21 GRADE: 6th SUBJECT: Science Teachers: Mars and Williams 16 ) Implement scientific principles to design processes for monitoring and minimizing human impact on the environment (e.g., water usage, including withdrawal of water from streams and aquifers or construction of dams and levees; land usage, including urban development, agriculture, or removal of wetlands; pollution of air, water, and land).* I CAN: Cite textual evidence to support analysis of what the text says explicitly as well as inferences drawn from the text. Determine a central idea of a text and how it is conveyed through particular details; provide a summary of the text distinct from personal opinions or judgments. Analyze in detail how a key individual, event, or idea is introduced, illustrated, and elaborated in a text (e.g., through examples or anecdotes). Determine the meaning of words and phrases as they are used in a text, including figurative, connotative, and technical meanings. ACTIVITY: Read the Science article and answer the following questions The Dust Bowl 1. There is no doubt that humans have significantly changed ecosystems since they first began roaming the Earth. Sometimes natural habitats are destroyed or damaged. At other times, human activities have caused the extinction of organisms. But most often these activities were not intentional. As humans entered new areas, they did not always know that their activities could hurt the environment. Often, the harm did not show until it was too late. Most often we have learned from those mistakes and have made changes that then benefit the very same environment. Let us look at an example where human activity had a negative impact but was later corrected. 2. One striking example happened as early Americans moved west in search of land and financial freedom. Before the westward expansion, most Americans lived east of the Mississippi River. This ecosystem was dramatically different from the ecosystem of the Great Plains in the Midwest. The eastern ecosystem received more rainfall and had rich soil and plenty of trees. The people from these areas used agricultural practices that worked very well in the eastern ecosystem. 3. When settlers moved west, they encountered an unfamiliar and wonderful landscape. The prairies of the Great Plains seemed endless and bountiful. Grasses grew taller than the head of a man riding on a horse. The rains seemed plentiful. There were no fences and few natural barriers such as mountains. This land looked as if it were theirs for the taking. This led newcomers to feel that they had limitless grazing potential for their livestock. They also felt that this land would serve as rich agricultural land. Ranchers let large herds of animals freely graze on the prairie year-round. Farmers broke through the thick sod created by the grasses and plowed fields. After World War I, farm machinery became mechanized, and farmers were able to plow larger and larger fields. One of the largest ecological disasters that this country has ever seen was on the horizon. Those early settlers had no clue that their farming and grazing practices would cause it. 4. The farming and grazing practices of the settlers severely affected the landscape. Overgrazing removed the lush grasses from the Great Plains. This activity removed the plant material above the ground. More importantly, it also removed the deep root systems that held the soils in place. Even worse, plows at that time overturned the soil and buried any plant material underground. And the settlers’ irrigation practices dried up the streams and rivers that fed the area. The result of all of these seemingly innocent practices left an ecosystem that would not be able to tolerate a drought. And in the 1930s, the drought came. 5. The country was already suffering from the Great Depression started by the stock market crash in September of 1929. Many people lost everything they had. This meant that there was no money available to help people in the country. This was especially hard for farmers and ranchers. Crop prices fell, and most of the people who had moved to the Great Plains found themselves in economic crisis. Some tried to plant more crops in order to make up the difference. But then severe drought hit the Great Plains. All of the crops that were planted could not tolerate the dry conditions and high heat, so they withered and died. Grasses could not grow for the livestock to eat, and many animals died. The once thriving Great Plains could no longer support life. But the worst part of the drought was the dust storms that were created. The root systems were no longer there to hold the soil. Relentless winds whipped up the loose topsoil into huge dust storms called “black blizzards.” These dust storms removed millions of acres of topsoil from the land, spinning it into the air. Many people came down with “dust pneumonia.” People could no longer live in the area. Over 60% of the people who lived in the Great Plains were forced to move. 6. As terrible as the Dust Bowl era was, many good things came from it. Farmers and ranchers realized that the practices they had used would not work in that environment anymore. The United States government set up new agencies to help bring the Great Plains back to life. The Soil Conservation Service was started in 1935. Its main job was to oversee the rebuilding of farmland. This organization worked together with farmers to make several important changes that are still used today. Grasses and trees were planted to recreate root systems that could hold the soil in place. Fields were terraced, or created in levels, allowing them to hold both irrigation water and rainwater. Perhaps most importantly, farmers were required to leave parts of their fields fallow for at least a year. This means that the farmers were not allowed to plow or plant on sections of their farms. This way, the land had a chance to “rest” between plantings. These changes went a long way toward restoring the Great Plains to their former glory. 7. Even today, measures are being taken to ensure that this country does not find itself in another Dust Bowl situation. New types of plows have been invented that break up the soil from underneath. This practice allows the majority of the plant material that is plowed to remain on top of the soil instead of getting buried. The former Soil Conservation Service is still around today but is now called the Natural Resource Conservation Service. Its job is to make sure that not only farmland is conserved, but all of the surrounding areas as well. The agency works to monitor air and water quality, as well as wildlife habitat. Our early settlers unknowingly caused a huge national disaster, but we have learned from their mistakes. Farming and ranching practices have changed forever in the hopes that we will never see another Dust Bowl. 1. Which statement about human activity and the environment is NOT true? a. Humans knowingly create environmental disasters. b. Humans affect ecosystems in many ways. c. Humans can create solutions to disasters. d. Humans have altered ecosystems for a long time.2 2. There were many aspects of the Great Plains that looked promising to early settlers. Which of the following was NOT one of those aspects? a. The Great Plains had endless grass. b. The Great Plains had plenty of rainfall. c. The Great Plains had lots of trees. d. The Great Plains had few natural barriers. 3. The farming and grazing practices of the early settlers led to a natural disaster. Which of the following practices led to the creation of this ecosystem disaster? a. Overplanting crops that could not stand drought b. Plowing the soils so that plant materials were buried c.Overgrazing the prairie d. All of the above 4. There were many factors that affected people who lived in the Great Plains during the Dust Bowl era. What was the main factor that drove people away from the Great Plains? a. The high temperatures. b. The low rainfall c. The crash of the stock market. d. The severe and frequent dust storm 5. Many efforts were made after the Dust Bowl to make sure that a disaster such as this never happened again. Which of the following was NOT one of those efforts? a. Farmers and ranchers changed their practices. b. Trees and grasses were planted. c. Fields were sloped to decrease water runoff. d. Farmland was left fallow for a year. 6. Use what you have learned in this passage to answer the following question. Which of the following statements is most true regarding this passage on the Dust Bowl? a. Human activity always hurts an environment. b. Humans are able to change practices to help an environment they have hurt. c. Natural disasters always happen in newly settled areas. d. There is nothing that humans can do to prevent natural disasters .
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