Appendix 5 1

Appendix 5. Relations between the YSI 6136 turbidity sensor, the YSI EXO 

turbidity sensor, and the HACH 2100AN turbidimeter using data collected from 

the Wamego and De Soto sites on the Kansas River, Kansas, during October 2012 

through September 2016

YSI 6136 turbidity, in formazin nephelometric units

0 50 100 150 200 250 300

YSI EXO turbidity, in formazin nephelometric units

0

50

100

150

200

250

300

1:1 Line

n=29 

Figure 5.1. Relation between YSI 6136 and YSI EXO turbidity sensor data collected from the Wamego 

and De Soto sites on the Kansas River during September 2013 through June 2014. 
2 Cyanobacteria and Associated Toxins and Taste-and-Odor Compounds in the Kansas River, Kansas

0 50 100 150 200 250 300

Difference (YSI 6136–YSI EXO)

-100

-80

-60

-40

-20

0

20

40

60

80

100

± 20 formazin nephelometric units

± 10 formazin nephelometric units

n=29 

YSI 6136 turbidity, in formazin nephelometric units

EXPLANATION

Figure 5.2. Relation between YSI 6136 turbidity data and the absolute difference between YSI 6136 

and YSI EXO measured turbidity data collected from the Wamego and De Soto sites on the Kansas River 

during September 2013 through June 2014.
Appendix 5 3

Relative percentage difference

0

20

40

60

80

100

20 percent

10 percent

EXPLANATION

0 50 100 150 200 250 300

n=29 

YSI 6136 turbidity, in formazin nephelometric units

Figure 5.3. Relation between YSI 6136 turbidity data and the relative percentage difference between YSI 

6136 and YSI EXO measured turbidity data collected from the Wamego and De Soto sites on the Kansas 

River during September 2013 through June 2014.
4 Cyanobacteria and Associated Toxins and Taste-and-Odor Compounds in the Kansas River, Kansas

Hach 2100AN turbidity, in nephelometric turbidity ratio units

0 200 400 600 800 1,000

Sensor-measured turbidity, in formazin nephelometric units

0

200

400

600

800

1,000

YSI 6136 (n=55)

YSI EXO (n=85)

Linear regression: YSI 6136; f=6.5257+0.0.8210 (YSI 6136)

Linear regression: YSI EXO; f=8.1489+0.7645 (YSI EXO)

1:1 Line

EXPLANATION

Figure 5.4. Linear regression between Hach 2100AN turbidimeter and YSI 6136 (October 2012 through June 2014) and 

YSI EXO (June 2014 through September 2016) sensor measured turbidity data collected from the Wamego and De Soto 

sites on the Kansas River.
Appendix 5 5

Hach 2100AN turbidity, in nephelometric turbidity ratio units

0 200 400 600 800 1,000

Difference (Hach 2100AN–turbidity sensor)

-200

-180

-160

-140

-120

-100

-80

-60

-4

-200

0

20

40

60

80

100

120

140

160

180

200

YSI 6136 (n=55)

± 20 formazin nephelometric units

± 10 formazin nephelometric units

YSI EXO (n=85)

EXPLANATION

Figure 5.5. Relation between Hach 2100AN turbidimeter and 1) absolute difference between Hach 2100AN 

and YSI 6136 measured turbidity data (October 2012 through June 2014) and 2) absolute difference between 

Hach 2100AN and YSI EXO measured turbidity data (June 2014 through September 2016) collected from the 

Wamego and De Soto sites on the Kansas River.
6 Cyanobacteria and Associated Toxins and Taste-and-Odor Compounds in the Kansas River, Kansas

0 200 400 600 800 1,000

Relative percent difference

0

20

40

60

80

100

Hach 2100AN turbidity, in nephelometric turbidity ratio units

YSI 6136 (n=55)

20 percent 

10 percent

YSI EXO (n=85)

EXPLANATION

Figure 5.6. Relation between Hach 2100AN turbidimeter and 1) relative percentage difference 

between Hach 2100AN and YSI 6136 measured turbidity data (October 2012 through June 2014) and 

2) relative percentage difference between Hach 2100AN and EXO measured turbidity data (June 2014 

through September 2016) collected from the Wamego and De Soto sites on the Kansas River.