Gravimetric processing from samples taken using corer.
| Date/Time | Location | Tare (g) | Wet (g) | Dry (g) | Density (g/cm^3) | Qsoil (cm^3/cm^3) % | EC5 Reading (cm^3/cm^3) % |
|---|---|---|---|---|---|---|---|
| 20 Feb 2015/1157 | bao, 2--5cm | 5.58 | 100.74 | 83.54 | 1.17 | 25.89 | 23.98 |
| 20 Feb 2015/1112 | bao, 10--13cm | 2.15 | 99.59 | 87.36 | 1.28 | 18.41 | 16.38 |
| 20 Feb 2015/1129 | bao, 20-23cm | 2.50 | 89.51 | 78.51 | 1.14 | 16.56 | 13.17 |
| 9 Mar 2015/1430 | ehs, 2--5cm | 16.477 | 152.333 | 127.741 | 1.67 | 37.02 | 28.4 |
| 20 Apr 2015/1500 | ehs,4--7cm | 8.237+8.260 | 81.960+60.946 | 29.47 | |||
| 20 Apr 2015/1500 | ehs, 9--12cm | 8.232+8.214 | 71.380+74.505 | 28.20 | |||
| 20 Apr 2015/1500 | ehs, 19--22cm | 8.265+2.139 | 96.082+29.133 | 26.00 |
Note: Dry taken 23 Feb after air-drying in the lab for 3 days, then baking in the toaster oven for an hour. (The oven got rid of about another 1.5g in each sample.)
The results show all EC5s about 2% low (which could be due to coupling to the soil, just after installation).
Note2: 9 Mar sample processed as 2 aliquots (since scale range was limited). The sum of both aliquots is shown in the above table.
Note3: 20 Apr sample also processed as 2 aliquots. Both are shown above.
Note4: Tried to get a better depth match with 20 Apr samples, moving the 1cm ring to the top.
Note5: 20 Apr EC5 readings taken using minicom – see teardown comment.
tare = c(5.58,2.15,2.50,16.477,8.237+8.260,8.232+8.214,8.265+2.139)
wet = c(100.74,99.59,89.51,152.333,81.960+60.946,71.380+74.505,96.082+29.133)-tare
dry = c(83.54,87.36,78.51,127.741)-tare
vol = 3*pi*(5.31/2)^2
rho = dry/vol
moist = (100*(wet-dry)/vol) # density numerically equal to volume mixing ratio since rho_water = 1.
ec5 = c(23.98,16.38,13.17,28.4)
matplot(moist,ec5,xlim=c(0,40),ylim=c(0,40)); abline(0,1,lty=2)