Canonical property vocabulary¶
The live registry at GET /v1/properties is authoritative. The vocabulary is developing and can change during the experimental period.
| ID | Standard unit | Current SDA support | Critical distinction |
|---|---|---|---|
ph |
pH | supported | solution and ratio matter |
organic_carbon |
% | planned | not inferred from organic matter |
organic_matter |
% | supported | analytical/estimation method matters |
sand, silt, clay |
% | supported | particle-size method and fraction limits matter |
cation_exchange_capacity |
cmol(+)/kg | planned | pH and extraction method matter |
bulk_density |
g/cm³ | supported | water tension and fragment treatment matter |
total_nitrogen |
% | planned | digestion/combustion method matters |
available_phosphorus |
mg/kg | planned | extractant defines “available” |
electrical_conductivity |
dS/m | supported | extract ratio/method matters |
calcium, magnesium, potassium, sodium |
mg/kg | planned | exchangeable and total values differ |
iron, manganese, zinc, boron |
mg/kg | planned | extractable and total values differ |
selenium, arsenic |
mg/kg | planned | digestion, detection limit, and matrix matter |
Aliases¶
Aliases help accept common names such as CEC, SOC, OM, EC, and element symbols. They do not erase method distinctions. A contributor adding an alias must demonstrate that it names the same property concept rather than a related measurement.
Conversion policy¶
Conversions are allowlisted and return a transformation object. OpenSoil does not currently convert organic matter to organic carbon, derive texture fractions, or translate extraction methods. Any new conversion needs a decision-log entry, test fixtures, precision rules, and documentation of scientific limits.