Seasonal Characteristics of Sinking Creek

The Study

During the year 1982-1983 Suzanne Ullensvang, a John Burroughs student, conducted a year long study of the creek (9). She collected biotic and abiotic measurements on one day of each month for 12 consecutive months. The abstract of her research report follows.

"Sinking Creek, a small Missouri Ozark stream, was the subject of a Twelve-month ecological study. Physical, chemical and biological conditions of the stream were measured at monthly intervals. The main objectives of the research were (1) determination of the presence, nature and relative degree of seasonal changes in water quality and bottom fauna community composition, and (2) determination of possible relationships in abiotic and biotic stream factors.

With few exceptions, seasonal variations were present and measurable. Fluctuations in levels of chemical stream factors were closely related to the seasonally affected physical factors of water temperature and stream discharge. However, deviations from the means were usually not large, indicating the general stability of abiotic stream characteristics. The chemical stability was illustrated by the small pH range in the well buffered stream. Trends in the invertebrate populations were more pronounced and showed a much greater degree of seasonal variability. These characteristics could be due to the breeding cycles of aquatic insects. Seasonal variations in diatom and coliform populations were also identified in Sinking Creek.

Statistical analysis of the data suggested strong relationships between some factors measured in the stream. Stream volume and water temperature were found to be the primary influencing factors in the stream. Dissolved oxygen and relative percent saturation levels as well as several invertebrate populations showed strong correlations to water temperature. Changes in carbon dioxide, alkalinity and hardness levels were closely correlated to seasonal variations in stream discharge. Other possible strong variable relationships were also revealed by the analysis.

The stream is an example of a seasonally influenced ecosystem that exhibits a noticeable degree of interdependence between physical, chemical and biological characteristics. Further, the measured water quality is high and confirms the general impression that the stream is unpolluted and remains in a pristine state. These characteristics make Sinking Creek an ideal laboratory for studies of a natural ecosystem."

1982-83 Biological Data

Monthly Counts for all Organisms (10 Surber Samples)

Organism Collected

 Apr

 May

 Jun

 Jul

 Aug

 Sep

 Oct

 Nov

 Dec

 Jan

 Feb

 Mar
Ephemeroptera

 35

 27

104

132

90

29

57

144

131

84

160

346

Trichoptera

 9

6

11

24

7

61

36

139

140

94

98

114

Gastropoda

13

50

114

173

89

95

58

26

27

10

12

20

Plecoptera

13

50

38

17

7

2

1

8

65

52

152

36

Diptera

1

18

0

6

2

6

4

29

11

6

20

24

Acari

2

8

13

15

8

6

3

13

4

16

22

64

Oligochaeta

19

10

11

0

0

4

0

6

11

12

40

32

Coleoptera Larva

2

2

9

6

4

13

59

4

8

8

0

4

Coleoptera Adult

0

1

10

8

9

6

0

1

5

6

8

12

Odonata

4

1

0

0

0

2

3

5

7

0

6

2

Decapoda

3

0

7

6

1

3

2

3

2

2

2

0

Megaloptera

1

7

2

2

0

1

0

0

0

0

2

0

Tricladida

0

0

0

0

0

0

0

2

0

0

0

0

Hirudinea

0

0

0

0

0

0

0

0

1

0

0

0

Conchostraca

0

1

0

0

0

0

0

0

0

0

0

0



1982-83 Chemical Water Test Data

Mean Monthly Values for all Physical and Chemical Tests

 Test

 Apr

 May

 Jun

 Jul

 Aug

 Sep

 Oct

 Nov

 Dec

 Jan

 Feb

Mar

 Air Temp. F.

 50

 79

 83

 88

 82

 73

 64

 67

 54

 46

 54

 52

Water Temp. F.

 55

 70

 72

 78

 74

 67

 65

 57

 45

 43

 47

 48

 Vol. X 1000 gal/min.

 105

 36

 38

 31

 94

 73

 48

 45

 63

 70

 42

 36

 Velocity ft./sec.

 3.5

 2.1

 1.2

 1.1

 2.2

 1.8

 1.7

 1.8

 3.0

 1.8

 1.1

 0.9

 D.O. mg/L

 10

 10

 9

 9

 10

 11

 7

 10

 11

 11

 11

 11

 CO2 mg/L

 8

 12

 14

 19

 15

 15

 14

 12

 14

 15

 18

 13

 pH

 8.7

 8.3

 8.3

 8.3

 8.1

 8.1

 8.0

 8.2

 8.4

 8.6

 8.1

 8.2

 Nitrate mg/L

 0.60

 0.55

 0.75

 0.70

 0.53

 0.70

 0.55

 0.53

 0.50

 0.70

 0.46

 0.60

 Phosphate mg/L

 0.10

 0.09

 0.08

 0.10

 0.05

 0.05

 0.04

 0.05

 0.07

 0.01

 0.11

0.10

 Alkalinity mg/L

 117

 165

 140

 140

 135

 130

 158

 94

 130

 140

 177

163

 Hardness mg/L

 150

 170

 165

 177

 143

 143

 155

 180

 135

 135

 183

153

 Turbidity JTU

 8.8

 6.2

 5.0

 10.0

 0.0

 2.5

 0.0

 0.0

 0.0

 0.0

 0.0

9.0

 Apparent Color

 17.5

 14.0

 0.0

 0.0

 0.0

 0.0

 0.0

 0.0

 0.0

 0.0

 0.0

0.0




The Forest Study Site
Stream and Forest References
Drey Land Page
JBS Home Page