Plant‑Soil Chemistry Dataset (Raja 2019 Field Campaign)

1. Overview  

This repository contains the final, cleaned chemistry data that were produced from the 2019 Raja field campaign.   The data combine:

• Plant tissue concentrations (leaf, bark, needles, …) for a set of selected elements.  
• Corresponding soil‑till depth, point location, lithology and basic tree information.  
• Element‑specific relative‑standard‑deviation (RSD) uncertainties that were calculated from laboratory‑derived uncertainty parameters.

All files are provided in CSV format (UTF‑8, , separator) and/or the R programming language binary format RData.

The exact set of tissue files depends on the species/plant‑parts that were sampled; the naming convention is pl + lower‑case abbreviation of the tissue (generated by abbreviate(Plant, minlength = 2) + PlantPart).

2. Column description (common to all tables)

| Column | Meaning | Type | |--------|---------|------| | PointID | Unique identifier for the sampling point (e.g., NEXT‑2019‑257). | character | | X / Y | Projected coordinates (Easting / Northing, EPSG 3067). | numeric | | Plant | Species name (full). | character | | PlantPart | Plant part sampled (Leaf, Bark, Fruit, …). | character | | Tissue | Short code: <abbr> <PlantPart> (e.g., Ac Leaf). | character | | Lithology_updated_Sol | Detailed lithology description from field notes. | character | | Lith_simpl | Simplified lithology (e.g., Mafic rocks). | character | | TillDepth_cm | Soil till depth at the point (cm). | numeric | | Element columns (e.g. Al, As, Ca, …) | Measured concentration or relative uncertainty, depending on the file (see below). | numeric | | Tissue (re‑appears) | Same as above – kept for convenience. | character |

2.1. Concentration vs. Uncertainty tables  

• Plant_all_final.csv – contains concentrations (units as reported by the laboratory, typically mg kg⁻¹).  
• Plant_uncensored_raw.RData – contains the very original, untreated data.  
• *_uncertainty*.csv  – the element columns have been replaced by their relative standard deviation (RSD), i.e. a unit‑less proportion (0.12 = 12 % RSD).  

If you need both concentration and uncertainty for a given point, use the two files together (join on PointID).

3. Usage notes  

• Joining concentration & uncertainty – the two CSVs 'plant' and 'plant_uncertainty' share the same column order and can be merged on PointID.  
• Missing values – NA indicates either a non‑detected element or that no uncertainty parameter was available for that element.  
• Spatial reference – coordinates are in ETRS89 / Lantmäteriet 3006 (EPSG 3067), suitable for Swedish national mapping.  
• Element selection – in the subdatasets not every element is present in every tissue file; only the elements that passed the QC selection criteria are kept.