H: Horizontal Position Index
General
Type: letters & numbers
The horizontal position index consists of a label followed by a number and describes the sampling point of a parameter or the location of an instrument.
Important: if eddy covariance equipment is installed on a structure, we refer to it as tower, never as a mast. A mast can be installed in close proximity of the tower and normally carries additional instrumentation (e.g. phenocam or similar) that did not fit on the main tower.
If we want to describe masts and booms that are mounted on the main tower, it is necessary to combine different labels and numbers. Please see below for examples. Naming is done clockwise, starting from North. As for the work in reality, adjusted naming as in case of two rain gauges next to a tower on separate small masts is possible: e.g. instead of PREC_RAIN_M1_1_1 and PREC_RAIN_M2_1_1 one could also name these PREC_RAIN_GF1_1_1 and PREC_RAIN_GF1_1_2. In all cases the detailed site overview in form of a scheme has to be provided.
List of H Indices
| wdt_ID | H Index | Horizontal Position |
|---|---|---|
| 1 | T | Tower (EC system is mounted here) |
| 2 | M | mast |
| 3 | TR | tree |
| 4 | FF | forest floor plot |
| 5 | GF | grassland floor |
| 6 | WF | wetland floor |
| 7 | CF | cropland floor |
| 8 | H | Hut |
| 9 | B | boom |
| 10 | BOX | box with mounted instrumentation (only if necessary, might be misleading according to Techs) |
Examples
| H Index | Example |
| T1 | main tower with installed eddy covariance equipment |
| T1B1 | boom on main tower |
| T1B2 | 2nd boom on main tower |
| M1 | mast where radiation sensors are installed in the field |
| M2 | 2nd mast with e.g. precipitation bucket |
| M2B1 | boom on 2nd mast |
| H1 | hut at measurement site |
| BOX1 | Box with devices, power supplies, etc |
| TREE5 | fifth tree with instrumentation |
| FF3 | forest floor plot 3 |
| GF5 | grassland floor plot 5 |
| WF2 | wetland floor plot 2 |
| CF0 | cropland floor that represents the overall ecosystem area (not assigned to a specific plot) |
| T2 | 2nd tower with eddy equipment |