You are viewing an old version of this page. View the current version.

Compare with Current View Page History

« Previous Version 9 Next »

Gravimetric processing from samples taken using corer.

Date/TimeLocationTare (g)Wet (g)Dry (g)Density (g/cm^3)Qsoil (cm^3/cm^3) %EC5 Reading (cm^3/cm^3) %Diff (cm^3/cm^3) %
20 Feb 2015/1157bao, 2--5cm5.58100.7483.541.1725.8923.98-1.9
20 Feb 2015/1112bao, 10--13cm2.1599.5987.361.2818.4116.38-2.0
20 Feb 2015/1129bao, 20-23cm2.5089.5178.511.1416.5613.17-3.4
9 Mar 2015/1430ehs, 2--5cm16.477142.333127.7411.6721.9628.46.4
20 Apr 2015/1500ehs,4--7cm8.237+8.26081.960+60.94670.854+52.1241.6030.0029.47-0.5
20 Apr 2015/1500ehs, 9--12cm8.232+8.21471.380+74.50562.335+65.1621.6727.6828.200.5
20 Apr 2015/1500

ehs, 19–22cm

(not completely full, by about 2mm?)

8.265+2.13996.082+29.13384.192+25.476

1.49

(likely low)

23.4026.002.6

22 May

2015/1400

bao, 3-62.126+2.37956.184+61.35347.071+51.421  30 
22 May 2015/1400bao, 8-112.111+2.09470.604+60.12259.922+50.764  32 
22 May 2015/1400bao, 18-212.079+2.10760.887+70.70251.568+59.764  29.5 

 

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.

Note6: assume that 9 Mar had a math error: 142.333, rather than 152.333???

 

tare = c(5.58, 2.15, 2.50, 16.477, 8.237+8.260, 8.232+8.214, 8.265+2.139, 2.126+2.379, 2.111+2.094, 2.079+2.107)

wet = c(100.74, 99.59, 89.51, 142.333, 81.960+60.946, 71.380+74.505, 96.082+29.133, 56.184+61.353, 70.604+60.122, 60.887+70.702)-tare

dry = c(83.54, 87.36, 78.51, 127.741, 70.854+52.124, 62.335+65.162, 84.192+25.476, 47.071+51.421, 59.922+50.764, 51.568+59.764)-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, 29.47, 28.20, 26.00, 30, 32, 29.5)

ch = as.character(c(1,2,3,1,1,2,3,1,2,3))

col = c(1,1,1,2,2,2,2,1,1,1)

plot(moist,ec5,xlim=c(0,40),ylim=c(0,40),col=col,pch=ch); abline(0,1,lty=2)

 

  • No labels