| TDR | FDR | |
|---|---|---|
Full name | Time-Domain Reflectometry |
Frequency-Domain Reflectometry |
Measurement principle | Checking appeared dielectric constant(Ka) and moisture(Vol) in soil. |
|
Transmission time of EM step pulse ∝ moisture in soil |
Change in Capacitance ∝ moisture in soil |
|
Generated waveform | Electromagnetic(EM) step pulse |
High Frequency transistor oscillator |
Wavelength range | 1MHz~1GHz |
1MHz~Hundreds of MHz |
Advantages | Rapid measure, Numerical stability regardless of earthiness and measurement density |
Rational cost(relatively low price compared to TDR) |
Disadvantages | High price |
Need calibration in accordance to earthiness and measurement density, vulnerable to soil salinization and organic matter. |
| property | screen | units | note |
|---|---|---|---|
| moisture | 25.6 | %(Vol) | WC, Water Content |
| salt | 0.08 | ds/m | EC, Elctrical Conductivity |
temperature |
26.1 | ℃ | Temp, Temperature |
category |
dry |
ordinary (0.3~15 pressure) |
excess |
note |
sand |
under 3 |
3~5.3 | above 5.3 |
plant impossibility |
sand loam |
under 7.3 |
7.3~18.8 | above 18.8 |
plant possibility |
loam |
under 10.2 |
10.2~26.0 | above 26.0 |
|
clay loam |
under16.6 |
16.6~28.6 | above 28.6 |
|
| clay | under 21.2 |
21.2~31.4 | above 31.4 |
plant impossibility |
improvement |
pour , spray |
- | pipe drainage |
| 구분 | Units | better | normal | bad |
worse |
|---|---|---|---|---|---|
| EC | ds/m | Under 0.2 |
0.2~1.0 | 10.~1.5 | Above 1.5 |
| temperature | ℃ | 20-25 | 20-25 | 20-25 | 20-25 |
transplant |
maintain |
|---|---|
- Checking the status of alien soil
- Doing real time analysis function the of soil |
- Checking the nutritive conditions of the soil - Checking the soil status(salinity condition) of the made groud and roadside
- Checking the soil moisture of the drought and the rainy season
|
Korean
Chinese
