8 March Science 8–Begin Water, Watersheds, Water Cycle

Turn in Summative project on Photosynthesis-Carbon Cycle.

Important blogpost today–tons of information and links–bookmark this and examine thoroughly so you know what is here.

Begin thinking about how human activity shifts the great biogeochemical cycles on EarthBe on the lookout for references you will need for your human impact projects.

Remember the quote below that we looked at in January?–read the short article that follows:

From S.E. Jorgensen, 1980, Lake Management:

‘PLANKTON. We’re an indolent lot… shiftless microscopic drifters. Here in the oceans a million trillion trillion of us just float aimlessly and worship the sun. We have no brains at all. And we don’t do anything except procreate with promiscuous abandon and generate most of the earth’s oxygen. And we have no advice at all for you diligent bipeds who use your capacious intellects to so industriously befoul the seas. For about two billion years we got along quite well without you. And Without us, you will suffocate.’


“Everything is connected”–consider the interconnections in the following recent article between the carbon cycle and the water cycle:

Forests and climate change: https://www.nytimes.com/2018/03/07/climate/forests-storms-climate-change.html

Look at this quote from an article in 1970. Think of how photosynthesis brings together the carbon cycle, the water cycle, and the oxygen cycle. How does “plant blindness” relate to the “anti-intellectualism” the scientists refer to in the final sentence? These ideas are being expressed in 1970!!! If people knew then, why do you think we are facing the same problems that have an even greater magnitude today?:

From “The Oxygen Cycle” by Preston Cloud and Aharon Gibor in the Sci. Am book The Biosphere (1970)

“What we want to stress is the indivisibility and complexity of  the environment. For example, the earth’s atmosphere is so thoroughly mixed and so rapidly recycled through the biosphere that the next breath you inhale will contain atoms exhaled by Jesus at Gethsemane and by Adolf Hitler at Munich. It will also contain atoms of radioactive strontium 90 and iodine 130 from atomic explosions and gases from the chimneys and exhaust pipes of the world. Present environmental problems stand as grim monument to the cumulatively adverse effects of actions that in themselves were reasonable enough but were taken without sufficient thought to their consequences. If we want to ensure that the biosphere continues to exist over the long term and to have an oxygen cycle, each new action must be matched with an effort to foresee its consequences throughout the ecosystem and to determine how they can be managed favorably or avoided. Understanding also is needed, and we are woefully short on that commodity. This means that we must continue to probe all aspects of the indivisible global ecosystem and its past, present and potential interactions. That is called basic research, and basic research at this critical point in history is gravely endangered by the new crosscurrents of anti-intellectualism.”

Focusing on Water, Watersheds, The Water Cycle–check out the following articles and links. Read, reflect, question, write.

Make a cartoon: Where does the water you use come from? Where does it go? What happens along the way?

See the picture below of a Tibetan refugee child studying the water cycle in a school in northern India–near Dharamsala. What makes this picture poignant and significant? Find out what you can about the Tibetan plateau and water. See the map at: http://www.meltdownintibet.com/images/plateaumap_lg.jpg


Competing claims about the water cycle?

“The water coming out of your kitchen tap is four billion years old and might well have been sipped by a Tyrannosaurus rex.”

“The earth’s oceans, ice caps, glaciers, lakes, rivers, soils and atmosphere contains about 1.5 billion cubic kilometers of H2O. It has been estimated that all the earth’s water is split by plant cells and reconstituted by the biota about every 2,000,000 years.”

Watershed–an important component of the water cycle

Find and reread the piece you wrote about rivers after WOW. Add thoughts since then about your WOW experience and any new experiences you have had with rivers and watersheds. (You may need to find out more about what a watershed is!).


Canoeing on the Missouri River–north of Kansas City just upstream from the confluence with the Kaw or Kansas River. On this trip, my brother and I canoed right through the city from the north to the east. The river makes a bend right at the confluence.

Consider the ways water behaves in the environment.

  • A watershed, catchment basin, or drainage basin is one of the most important landforms related to living things in the environment, including humans.
  • Right now you are living in the Yamuna Watershed. Where does the water come from in our watershed? Where does it go? What happens to the water in this watershed?
  • Describe your WOW rafting adventure. What in that experience relates to the watershed?
  • Read Poet and Environmentalist Gary Snyder’s “We Wash Our Bowls” http://www.smith.edu/poetrycenter/poets/wewashourbowls.html
  • How does Snyder regard water and watersheds?

Learn how to set up the stream table.

  1. Learn how to operate the siphon.
  2. Learn how to make observations:

Activity 1 – Flat, Inclined Terrain Model

  1. Create a slightly inclined plane.
  2. Predict what will happen when the water is turned on. Turn on the water so that it pours in a steady, moderate stream.
  3. Record observations in 5-minute intervals for about 20 – 30 minutes. Include sketches and photos at each interval. You may try 30-second video segments, too. Try to make a time lapse record.
  4. Turn the water off after 20 – 30 minutes. Discuss the similarities or differences between the two models. What were their observations? Did each model have the same result? How did the landscape influence the course of the river?
  5. Refill the water jug to prepare for the next experiment.

Activity 2 – Hills and Valleys Landscape Model

  1. Remold the sand in the tray to create a surface with several hills and valleys.
  2. Predict what you think will happen in this scenario. Will the same river formation happen? Turn on the water so that it pours in a steady, moderate stream. Table is at same inclination as model 1.
  3. Record observations in 5-minute intervals for about 20 – 30 minutes. Include sketches and photos at each interval. You may try 30-second video segments, too. Try to make a time lapse record.
  4. Turn the water off after 20 – 30 minutes. Discuss the similarities or differences between the two models. Did each model have the same result? How did each landscape influence the course of the river? How were the results different or the same, compared to the flat and inclined model?

What’s Happening?
If you’ve been in mountains and seen a spectacular waterfall, you probably were looking at the beginning of a river. Most rivers begin on top of mountains where water from rain or melting snow collects. Under the influence of gravity, this water flows downhill to form brooks, streams or rivers. As the stream or river flows downhill, it can change the landscape by eroding rocks and depositing sediments.

Some observations that can be made by comparing both models are:

  • The speed of the water flowing downhill will be affected by the degree of incline, and any structures or topographical features in its path.
  • The faster the water flows, the more erosion occurs.
  • Water flowing downhill moves and deposits sand at the bottom of the river. The faster the water flows, the more sand will be deposited at the bottom. A delta at the mouth of a river forms in the same way.

Although the formation of the “rivers” in this activity appeared very quickly, in reality rivers can take millions to billions of years to form a path from land to sea.

More Discussion

  • How would the river formation be affected if the water continued to flow for one hour, two hours or three hours?
  • How would the river formation or pattern be affected if the sand were replaced with soil?
  • How can the stream table be used to simulate a landslide? What variables could be changed to induce a landslide?
  • What are some kinds of man-made structures or human activities that can affect a river system? Can students name American rivers that are being affected in these ways?
  • Can students name an important American river that does not originate in mountains?

Extended Activity 3
Extend the activity by changing some of the variables to observe how it affects the river’s path and speed, or the erosion and deposition of sand. Students can create their own variables to test or try one of the following:

  • Place other objects in the sand, such as small pebbles, stones or small plastic houses or trees.
  • Build a dam in the middle the river.
  • Place two or three water jugs next to each other and turn all spigots on at the same time.
  • Mold the sand into a valley. Compare the differences when the water flows directly down the middle, to what happens when the water flows from the inclined section of the valley (the long side of the tray).


You and your group will need to decide how to illustrate, describe, and explain your stream simulation investigation in a multimedia presentation. Judicious use of photos, videos, diagrams, graphs, and data are an important part of the presentation. Be sure to attend to the following:

  • Experimental methods
  • Control of variables
  • Repeated trials
  • Observables (descriptive, quantitative—counts and measures)
  • Analysis and Interpretation
  • Explaining the observed simulated river landforms—their origin and development–principles and mechanisms of the effect of flowing water on the landscape and the effect of the landscape on the way water flows)
  • Links to actual river landforms
  • Tests of the explanations (evidence is gathered to support or challenge explanations)
  • Organization and display of data
  • Clarity, completeness, and accuracy of the presentation
  • Big ideas—significance of watershed to the water cycle; importance of people understanding watersheds with regard to human impact on the environment

Other references:


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