Introduction to Water Quality
Student Worksheet 
 

Purpose:
    The determination of water quality is the primary focus of this module. It is important that users have a working knowledge on controlling factors of water quality. In order to determine water quality, various measurements including biotic as well as abiotic factors will have to be considered. Among these are organisms present, pH, temperature, turbidity, salinity, and level of pollutants. Changes in these quantifiers can alter the chemistry of the aquatic environment and the life forms present.

    All aquatic environments are not the same, therefore, water quality is a relative term dependent on the particular environment studied. A marsh will not exhibit all of the same characteristics as a freshwater pond or an ocean. These unique characteristics refer to both biotic and abiotic factors. Depending on the characteristics exhibited by the aquatic environment, certain plant and animal life will be present. Changes in systems due to naturally occuring events such as hurricanes, flooding, etc. are also factors which alter abiotic factors. In order to offer any validity to test results, an understanding of aquatic environments must be attained.

    Vocabulary:
        abiotic
        aquatic environment
        biotic
        pH
        phosphates
        pollutant
        nitrates
        runoff
        salinity
        turbidity

Data:
 
 
Unknown 
pH
temperature (oC)
Nitrate (ppm)
Phosphate (ppm)
1
6.6
25.0 
0.5
1.0
2
7.5
30.0 
1.0
0.8
3
5.2
25.0 
0.2
0.0

 
 
 
Known Samples
pH
temperature (oC)
Nitrate (ppm)
Phosphate (ppm)
Pond
6.6
28.1
0.5
1.0
 
6.4
27.9
0.5
0.9
Campus
5.0
26.0
0.1
0.2
 
5.5
25.5
0.3
0.1
Creek
6.9
25.0
0.5
0.7
 
7.0
25.5
0.8
0.7
Near Drainage Ditch
7.0
30.0
1.0
0.8
 
7.3
28.5
1.5
0.9
 

Conclusions/Analysis:
One of the groups forgot to label their samples, using the data provided can you help them find the source of their unknowns?
 
Unknown
pH
Nitrates (ppm) 
Temperature (oC)
Predicted Known
pH
Nitrates (ppm)
Temperature (oC)
1
6.6
0.5
25.0
 
 
 
 
2
7.5
1.0
30.0
 
 
 
 
3
5.2
0.2
25.0
 
 
 
 
 

        1.   What characteristics of the water samples were most helpful in identification?
                

a.
b.

 
 

        2.    List some biotic and abiotic indicators that help in identification of water quality.
 
BITOIC INDICATORS
ABIOTIC INDICATORS
 
 
 
 
 
 
 
 
 
        3.    Construct a bar graph to show nitrate and phosphate levels of each site included in the
                data table. Rank the sites in order of decreasing quality in the table provided.
 
 

 
 
 
     
 
 

        3.    Construct a map to show the approximate source of each sample. Label each site on the
               map with the appropiate pH, temperature, nitrate, and phosphate levels.

Extensions:
       1.  The JASON project is an excellent online tool for various investigations. It has several
            aquatic environment lab investigations you might find useful. Check it Out!

       2.  Collect water samples that boundary these areas and observe growth of duckweed or
            any other bioindicator, such as algae.

       3.  Analyze your environment. What is the relationship between human activities and the
            environment? i.e. changing oil, fertilizing the lawn, littering,etc.

       4.  Study different aquatic biomes and indicate abiotic and biotic factors characteristic of each.
            Report to the class.