Experimental Design

9th Grade EICSeptember 28, 2010

Make Observations

Use your senses to notice the environment around you.

Define the Problem

Our problem is the mismanagement of riparian zones in the Atlanta area.

State a Hypothesis

A hypothesis is a testable idea or explanation that

leads to a scientific investigation.

How does the immediately adjacent terrestrial ecosystem have a direct effect on the riparian zone?

The Following Three Hypothesis are associated with Supporting

Question #1:

Possible Hypothesis Associated with Supporting Question #1

Possible Hypothesis

1)Plants in the riparian zone area contribute to the health of the

riparian zone.

2) There is no evidence of erosion

of the riparian zone area.

3) There is no evidence of runoff

(from agriculture, roadways or

household waste)

in the riparian zone area.

Possible Hypothesis Associated with Supporting Question #1

The Following Three Hypothesis are associated with Supporting

Question #2:

Does the riparian ecosystem have a direct effect on the immediately adjacent aquatic ecosystem?

1) Animals in the stream are indicators

of a healthy (unpolluted) stream.

2) There are no nitrates or phosphates

present in the water samples from

the stream.

3) There is no evidence of

sedimentation in the stream.

Possible Hypothesis Associated with Supporting Question #2

Design the experiment to pinpoint cause & effect

relationships

Experiment

Variable – the factor of interest

Experiment Group – receives the treatment

Control Group – does not receive the treatment

The Vocabulary of Experiments

Collecting & Analyzing Data

Data may be qualitative

(expressed with words)Or quantitative

(expressed with numbers).You may collect both types of data during one experiment.

•Examples of data you may collect:

Water samplesIdentification of aquatic, riparian & terrestrial plants & animals indicative of presence or absence of pollutionExamination of riparian zones for erosion or other signs of degradation

•Examine your data

•Discuss the findings with your team

•Make a decision concerning the correctness of your hypothesis

Draw Conclusions

•Use graphs, written reports and pictures to communicate your findings.

•You will do this with your team during a triboard presentation at the end of Fall semester.

Communicating Results

How to Asses Your Hypothesis

You may find the following slides helpful to you as you make a decision to accept or reject your hypothesis.

Indicators of an Unhealthy Riparian Zone

1.Low water table (level)2. Low forage production (food)

for fish and wildlife

3. Little shade-Warm water4. Poor fish habitat-Poor water

quality5. Low wildlife habitat diversity

Indicators of an Unhealthy Riparian Zone (cont.)

6. Little vegetation & roots to help protect and stabilize banks

7. Significant erosion of stream banks and shorelines

8. Repeated dredging of ditches, streams, and reservoirs

9. Reduced late summer stream flows.10. Decreased riparian property values.