Campbell HydroSense II HS2, Руководство по эксплуатации продукта

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HS2 and HS2P
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6.4.1 Soil Types
An RWC value greater than 100% indicates that the soil has a water content
value greater than the “wet” reference; a negative value indicates that the water
content is below the “dry” reference.
Water required (in mm of applied water) to return the soil to the “wet”
reference is also calculated and reported as water deficit. A negative deficit
indicates that the water content is greater than the “wet” reference for that soil
type.
Since the sensors average water content along the length of the rods, the
sample volume difference between the 20 cm and 12 cm sensors is significant.
This difference affects the water deficit value. Therefore, the current
measurement and reference values must be made with the same rod length.
The HydroSense II needs three parameters to calculate relative water content
and deficit:
• “wet” water content set point
• “dry” water content set point
•
sensor length
These parameters are soil specific and grouped as “soil profiles”. The
HydroSense II holds up to 10 soil profiles labe l led “SOIL 1” through “SOIL
10”.
Some soil profiles are preset to default values. These values may be used or
overwritten as desired, but take care to record what soil type is used for each
profile. The default soil profiles are described in TABLE 6-1 , Default Soil
Profiles .
TABLE 6-1. Default Soil Profiles
Soil No “Dry” “Wet” Rod Length Soil Description
1 7% 15% 20 cm Sand
2 10% 20% 20 cm Sandy Loam
3 18% 35% 12 cm Sandy Clay
4 15% 30% 12 cm Loam
5 20% 40% 12 cm Silty Clay
6 17% 35% 12 cm Clay Loam