East Side Middle School, Manhattan

Summer 2001

What Impact Do Humans Have on the Environment?

A Standards driven project that seeks to create a scientific understanding of, and appreciation for, The Hudson River.

Project Description

Government agencies cannot control all the collective and individual actions that may harm our environment; thus it is important for everyone to play a role in the stewardship of the natural world.  To this end, the goal of this project is to create an opportunity for students to develop a student-based river monitoring program that will lead to an understanding of how the natural world affects our lives and in turn, how we impact the natural world.

By focusing on a nearby local body of water, The Hudson River, students in the East Side Science Club will explore the impact that humans have on one of New York’s watersheds by conducting a variety of laboratory experiments and activities which will prepare them for a culminating watershed investigation.

Introductory Laboratory Experiment

The first task is for students to have an opportunity to investigate how the slope of a stream or river and the volume of water it contains affect its speed by interpreting data to see how different factors affect water flow.

Problem:       *Start a discussion with students about why different water systems travel at different speeds.  Ask them to create a problem (similar to the one above) that they can then solve in class.

“How do the slope of a river and the volume of water it contains affect its speed?”

Materials:       meter stick, pencils, wooden blocks, water, stopwatch, plastic tub, 2 100 ml beakers, rain gutter section, and food coloring in a squeeze bottle.

Procedure:       *Challenge students to create a step by step procedure that they will then follow in order to solve their problem. (Similar to            below)

¨     Mark an “S” at one end of the gutter representing the stream source.  Mark and “M” at the other end of the gutter representing the stream’s mouth.

¨     About 10 cm from the source end, draw a dark line across the inside of the gutter and measure 100-cm toward the mouth end from the first line.  Draw a second line across the gutter.

¨     Place the plastic tub under the mouth of the gutter to collect the water.

¨     Place enough blocks under the source end to raise it 5 cm above the tub.

¨     Record the number of blocks on a data chart.

¨     Slowly pour water from one beaker into the source end of the gutter.  A second person should add one drop of food coloring at the source end, above the “S” line.  A third person should begin timing when the food coloring first reaches the “S” line.  Stop timing when the food coloring reaches the “M” line.  Record the time on data table.

¨     Complete steps above for a second time, but increase the water volume in the stream by pouring from two beakers at the same time.

¨     This time increase the slope of the stream by adding blocks to raise the source end 5-cm higher.

¨     Complete steps again continuously raising the water volume and slope.  Record results.

Results & Discussion:

*Challenge students to calculate the average stream speed for each experiment.

(Speed of stream cm/s = distance (100 cm/average time s)

*Discuss the different results obtained by the groups in the class.

Questions:

¨     How did the speed of the stream change when you increased the volume of the water?

¨     How did the speed of the stream change when you increased the slope?

¨     How can this experiment help us in understanding how pollution moves through the Hudson River?

Have students create additional questions for discussion.

Standards

The implementation of this project will provide a host of opportunities for students to meet both the national and New York State Science Standards.

A list follows:

# Physical Science

¨     properties and changes of properties of objects and materials

¨     transfer of energy and the nature of a chemical reaction

¨     the water cycle

¨     motion and forces

# Earth Science

¨     geo chemical cycles, such as conservation of matter, chemical resources and movement of matter between chemical reservoirs

¨     natural resource management

¨     properties of earth materials, such as water and gases and the properties of rocks and soil

¨     energy in the earth system