Campbell Scientific Sentek TriSCAN® Manual v 1.2a User Manual
Page 48
TriSCAN Manual Version 1.2a
Copyright © 1991 – 2004 Sentek Pty Ltd All rights reserved
Page 41
Appendix 1. Units of Salinity Measurement and
Conversion Factors
Table 6. Useful Conversion Factors
Electrical Conductivity 1 Scm
-1
(1 mhocm
-1
) = 1000 mScm
-1
(1000 mmhoscm
-1
)
1 dSm
-1
= 1000
µ
Scm
-1
(1000 micromhoscm
-1
)
Conductivity to mmol (+) per liter:
mmol (+)/L = 10 X EC (EC in dSm
-1
)
for irrigation water and soil extracts in the range of 0.1 – 5 dSm
-1
Conductivity to osmotic pressure in bars:
OP = 0.36 x EC (EC in dSm
-1
) or soil extracts in the range of 3-30 dSm
-1
Conductivity to Total Dissolved Solids (TDS) mgL
-1
:
TDS (mgL
-1
) ˜ 640 x EC (dSm
-1
) for water and soil extracts having conductivity up to 5 dSm
-1
TDS (mgL
-1
) ˜ 800 x EC (dSm
-1
) for waters and soil extracts > 5 dSm
-1
TDS (lbs/ac ˜ ft) = TDS (mgL
-1
) x 2.72
TDS (tons/ac ˜ ft) = TDS (mgL
-1
) x 0.00136
Note: The SI unit of electrical conductivity is Siemens per metre (Sm
-1
). The equivalent non-SI unit is mho
and 1 mho = 1 Siemens.