| RecType | | Physical quantity | Record type |
| RecYear | | Physical quantity | Year of record |
| RecMonth | | Physical quantity | Month of record |
| RecDay | | Physical quantity | Day of record |
| Plot_2017 | | Nominal | Plot designation in 2017, after irrigation lines were shifted |
| Depth | | Nominal | Depth of soil sampling: "u" is 0-10 cm, "l" is 10-20 cm. The lower sampling was only possible in the uplands |
| Live | | Physical quantity | Oven-dried mass of live roots in a 5-cm radius, 10-cm depth cylindrical soil sample.
|
| Dead | | Physical quantity | Oven-dried mass of dead roots in a 5-cm radius, 10-cm depth cylindrical soil sample.
|
| N_live | | Physical quantity | Nitrogen concentration by mass of live roots in a 5-cm radius, 10-cm depth cylindrical soil sample.
|
| C_live | | Physical quantity | Carbon concentration by mass of live roots in a 5-cm radius, 10-cm depth cylindrical soil sample
|
| Current | | Nominal | Treatment in 2017, after irrigation lines were shifted. |
| Replicate | | Nominal | Irrigation line: (A) started in 1991, (B) started in 1993. |
| Replicate_ed | | Nominal | Irrigation lines as in "Replicate", but divided into uplands and lowlands to yield spatial "blocks". |
| Transect_1993 | | Nominal | Previous treatment (1991-2016). |
| Plot_1993 | | Nominal | Plot designation 1991-2017, before irrigation lines were shifted. Plots that are currently in the reduced (R) treatment did not have plot numbers during this time
|
| Plot_1992 | | Nominal | Plot designations in 1992, while second irrigation line was being added. These plot designations are not typically used.
|
| notes | | Nominal | Any notes about samples. |
