Campbell Scientific TDR Probes CS605, CS610, CS630, CS635, CS640, CS645 - Manual (Page 12)

TDR Probes CS605, CS610, CS630, CS635, CS640, CS645
can affect the accuracy and resolution of water content measurements.
FIGURE 7-2 presents a series of waveforms when a solution with an electrical
conductivity of 1.0 dS m
-1 is added to a soil which has essentially no salt
present. FIGURE 7-3 shows data for solution with high electrical conductivity.
water content = 9.5%
water content = 25%
FIGURE 7-2. Waveforms collected in a sandy loam using CS610 probe
with RG8 connecting cable. Volumetric water content values are 10,
16,18, 21 and 25%. Solution electrical conductivity is 1.0 dS m
-1 .
water content = 18%
water content = 37%
FIGURE 7-3. Waveforms collected in a sandy loam using CS610 probe
with RG8 connecting cable. Volumetric water content values are 10,
18, 26, 30 and 37%. Solution electrical conductivity is 10.2 dS m
-1 .
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