Skills Worksheet Concept Review In the space provided, write the letter of the description that best matches the term or phrase. 1. condensation 2. floodplain 3. watershed 4. tributary 5. evapotranspiration 6. discharge 7. desalination 8. delta 9. precipitation 10. alluvial fan a. any form of water that falls to Earth s surface from the clouds, including rain, snow, sleet, and hail b. change of state from a gas to a liquid c. the process of removing salt from ocean water d. area along a river, formed by sediments deposited when the river overflows its banks e. fan-shaped mass of rock material deposited by a stream on land where the slope decreases sharply f. area of land drained by a river system g. fan-shaped mass of rock material deposited at the mouth of a stream into another body of water h. volume of water moved by a stream in a given time period i. the total water loss from an area by evaporation and transpiration j. stream that flows into a lake or into a larger stream In the space provided, write the letter of the answer choice that best completes each statement or best answers each question. 11. A river system begins to form in a given area when a. evapotranspiration exceeds precipitation. b. precipitation exceeds evapotranspiration. c. precipitation exceeds condensation. d. condensation exceeds precipitation. 12. What happens over time as a stream s channel erodes? a. The stream becomes a watershed. b. The stream becomes a valley. c. The stream becomes a river d. The stream dries out. Holt Earth Science 1 River Systems
Concept Review continued 13. When precipitation exceeds evapotranspiration and runoff, a. soil becomes dry and irrigation is necessary. b. soil becomes moist and wind increases. c. soil becomes dry and flooding is possible. d. soil becomes moist and flooding is possible. 14. Which of the following factors affect the water budget? a. temperature, vegetation, wind, rainfall b. rock formation, conservation, rainfall, supply costs c. purification costs, water management, conservation, rainfall d. desalination, conservation, cost of land, rainfall 15. Which of the following are stages of the water cycle? a. transportation, deposition, precipitation b. evapotranspiration, condensation, precipitation c. evaporation, transmutation, participation d. transubstantiation, condensation, precession 16. Why do people choose to live in floodplains? a. There is access to fishing and the soil is rich. b. Floods can be overcome. c. Water drainage is good. d. The soil is good for housing development. 17. Which of the following are methods of water conservation? a. encouraging pollution b. damming rivers c. reducing evaporation and condensation d. enforcing conservation laws 18. Which of the following affect erosion caused by a river? a. acid rain and pollution b. rocks and sand c. discharge and gradient d. watersheds and floods 19. Which is a direct method of flood control? a. soil conservation b. dam c. natural levee d. valley 20. A lake forms when a. two or more rivers meet. b. a river runs dry. c. condensation occurs. d. precipitation collects in a depression. Holt Earth Science 2 River Systems
Skills Worksheet Critical Thinking ANALOGIES In the space provided, write the letter of the pair of terms or phrases that best complete the analogy shown. An analogy is a relationship between two pairs of words or phrases written as a:b::c:d. The symbol : is read is to, and the symbol :: is read as. 1. sediment : levee :: a. dam : floodplain b. night : evening c. million : thousand d. gravel : concrete wall 2. water : ocean :: a. ice : land b. vapor : river c. vapor : atmosphere d. ice : lake 3. condensation : liquid :: a. freezing : solid b. sediment : rock c. night : day d. solid : gas 4. tributary : river :: a. week : millennium b. spring : summer c. capillary : vein d. lake : ocean 5. dam : flood control :: a. pollution : pollution control b. insecticide : crop damage c. levee : pollution d. stop sign : street 6. precipitation : lake:: a. deposition : delta b. rain : water c. rock : water d. condensation : ocean 7. stream discharge : stream load :: a. rock : water b. sand : sediment c. volume : sediment d. water in : water out 8. delta: alluvial fan :: a. Mississippi : Minnesota b. triangle : fan c. water : land d. land : water 9. meander : straight river :: a. fast : slow b. slow : fast c. summer : winter d. volume : deposition Holt Earth Science 3 River Systems
Critical Thinking continued INTERPRETING OBSERVATIONS Read the following passage, and answer the questions below. In ancient Upper Egypt, the environment around the Nile River influenced where people settled and also where they buried their dead. They built a majority of their settlements on the floodplain, while they usually buried their dead in the desert margins beyond the floodplain. As a result of these decisions, most settlement sites have been covered by silt or washed away. There are few settlement sites for archaeologists to study, but there are many burial sites. Also, the river valley was narrower in ancient times (more than 7,000 years ago), consequently some burial sites dating to those times have been lost. 10. Why do you think the people of ancient Upper Egypt built settlements where they did? Explain your answer. 11. Why do you think the people of ancient Upper Egypt buried their dead where they did? Explain your answer. 12. Why do you think there are many burial sites of ancient Upper Egypt for archaeologists to study? Explain your answer. 13. Why have some burial sites of ancient Upper Egypt been lost? Explain your answer. Holt Earth Science 4 River Systems
Critical Thinking continued AGREE OR DISAGREE Agree or disagree with the following statements, and support your answers. 14. A stream s load, discharge, and speed will determine whether or not it eventually becomes a river. 15. The Mississippi River Delta is sediment deposited on land at the mouth of the river. 16. Evaporation and transpiration are part of the water cycle. 17. More than two-thirds of the Earth is covered with water, but only a small percentage of it is usable fresh water. Holt Earth Science 5 River Systems
Critical Thinking continued REFINING CONCEPTS The statements below challenge you to refine your understanding of concepts covered in the chapter. Think carefully, and answer the questions that follow. 18. Why is the river immediately downstream from Niagara Falls extremely turbulent? Explain your answer. 19. The polar icecaps have a large volume of fresh water. What are some practical considerations of using this water as a source for human consumption? 20. Why would a forest fire that occurs in a floodplain have a devastating impact? Explain your answer. Holt Earth Science 6 River Systems
Skills Worksheet Graphing Skills Pie Graphs and Personal Water Usage Scientists use pie graphs to communicate data, specifically to make it easy to visualize how many parts make up a whole. Pie graphs often are composed of percentage data in sections, with the total equal to 100%. Scientists might use a pie graph like the one below to show the breakdown of average annual water consumption in one United States county. The data in this pie graph is hypothetical. Annual Water Usage in County by Sector Manufacturing 25% Farming & irrigation 38% Household 37% PRACTICE Use the pie graph above to answer the following questions. 1. How much of the total water used annually in the hypothetical county is used for manufacturing? 2. How much of the total water used annually in the county is used for farming and irrigation? 3. Which category represents 25% of the total annual water usage in the county? 4. Which category represents 37% of the total annual water usage in the county? Holt Earth Science 33 River Systems
Graphing Skills continued 5. Imagine you want to show a pie graph of the breakdown of average individual water usage in your town. From the data below, create a pie graph. The data is hypothetical. Personal Water Use Percentage Drinking & Cooking 10 Bathing 15 Washing Clothes & Dishes 30 Watering Lawns 25 Removing Waste 20 Holt Earth Science 34 River Systems
Skills Worksheet Math Skills Scientific Notation and River Systems It is common in science to deal with very large or very small numbers. For example, the number used to express the volume of water in a river could be very large. Using scientific notation, however, makes it possible to represent large numbers without the place-holding zeros. Using scientific notation makes these numbers easier to read and write. In scientific notation, the number is written as a product of two factors. The first is a number between 1 and 10, and the second is a power of 10. The number therefore would be written X 10 exponent. To write a number in scientific notation, you first identify which digits are not place-holding zeros, and then put the decimal point after the leftmost non-zero digit. Then determine the exponent for the factor of 10 by counting the number of places the decimal point was moved. If the decimal point was moved to the left, the exponent will be positive. If the decimal point was moved to the right, the exponent is negative. SAMPLE PROBLEM: The amount of water that evaporates into the atmosphere yearly is about 500,000 km 3. A cubic kilometer has one billion cubic meters. Therefore, 500,000 km 3 would equal 1,000,000,000 500,000 or 500,000,000,000,000 m 3. Use scientific notation to express the amount of water that evaporates into the atmosphere each year. SOLUTION Step 1: Identify the number without place-holding zeros. The number is 5. Step 2: Place the decimal point after the left-most non-zero number. 500,000,000,000,000; the decimal would be placed to the right of 5. Step 3: Find the exponent by counting the number of places that the decimal point was moved. The decimal was moved 14 places to the right. Step 4: The final answer is 5 10 14. Holt Earth Science 31 River Systems
Math Skills continued PRACTICE Using the sample problem as a guide, answer the following questions. Remember to show your work. 1. The United States has more than 250,000 rivers. These rivers total about 3,500,000 miles. Express the total number of river miles in scientific notation. 2. Each person in the United States uses about 95,000 L of water each year. Expressed in scientific notation, how many liters of water does each person use annually in the United States? 3. The World Health Organization estimates that severe water shortages are affecting 400 million people worldwide. What is this number expressed in scientific notation? 4. If a stream has an hourly discharge of 2,640,000 L, what is its discharge expressed in scientific notation? Holt Earth Science 32 River Systems
Assessment Chapter Test A Chapter: River Systems MATCHING In the space provided, write the letter of the definition that best matches the term or phrase. 1. floodplain 2. evaporation 3. watershed 4. alluvial fan 5. evapotranspiration 6. precipitation 7. condensation 8. transpiration 9. delta 10. desalination a. land area drained by a river system b. total water loss from an area, given off by the land and bodies of water c. water that falls to Earth d. the process by which plants release water vapor into the atmosphere e. the process of removing salt from ocean water f. land area that may be covered with water when a river overflows g. fan-shaped mass of rock deposited at the mouth of a stream h. the change of state from a gas to a liquid i. the process by which liquid water changes into water vapor j. fan-shaped mass of rock that forms on land MULTIPLE CHOICE In the space provided, write the letter of the answer choice that best completes each statement or best answers each question. 11. A watershed is a. any stream. b. the area covered by water in floods. c. the area drained by a river system. d. a glacial lake. 12. What is a tributary? a. a stream that feeds another stream or lake b. a stream that dries out c. a lake that feeds into a stream d. the area drained by a river system Holt Earth Science 38 River Systems
Chapter Test A continued 13. A divide a. separates floodplains. b. separates continents. c. separates watersheds. d. separates braided streams. 14. An artificial levee is a form of a. flood control. b. pollution control. c. ecology. d. evapotranspiration. 15. Which of the following factors affect the water budget? a. geology, conservation, desalination b. income, expenses, outflow c. climate, vegetation, temperature d. economics, conservation, water usage 16. What is a main condition needed for a river to develop? a. The water budget is balanced. b. Precipitation exceeds evapotranspiration. c. Evapotranspiration exceeds precipitation. d. Condensation exceeds precipitation. 17. How does a river s speed affect how much it erodes its channel? a. The faster the river, the slower it erodes the river channel. b. The slower the river, the faster it erodes the river channel. c. Slower rivers cause virtually no erosion. d. The faster the river, the faster it erodes its channel. 18. What is an early step in the formation of a lake? a. Evaporation exceeds precipitation. b. A river overflows its banks. c. Erosion causes a valley. d. Water collects in a depression. 19. Which of the following factors widen and deepen a river channel? a. load, discharge, gradient b. acidity, sediment, erosion c. meanders, watersheds, divides d. fish, organic sediment, soil 20. River channels lengthen and branch out at their upper ends in what process? a. channel erosion b. headward erosion c. headward expansion d. headlong expansion Holt Earth Science 39 River Systems