WRB-canonical: layer(s) with andic OR vitric properties, combined thickness \>= 30 cm within 100 cm starting \<= 25 cm; OR \>= 60% of the entire soil thickness when a limiting layer starts 25-50 cm. Plus: no argic, ferralic, petroplinthic, pisoplinthic, plinthic or spodic horizon \<= 100 cm (unless buried below 50 cm).
Arguments
- pedon
A
PedonRecord.- min_thickness
Numeric threshold or option (see Details).
- max_top_cm
Numeric threshold or option (see Details).
- buried_below_cm
Numeric: layers of the exclusion diagnostics whose top_cm \>= this depth are treated as buried and do NOT exclude the Andosol (default 50, per WRB 2022 Ch 4 p 104).
Details
v0.3.4 enforces (1) andic OR vitric AND (2) combined thickness \>= 30 cm starting in the upper 25 cm AND (3) the negative-list exclusions on argic / ferralic / plinthic / spodic.
v0.9.85 buried-exclusion fix
WRB 2022 Ch 4 p 104 specifies the Andosol exclusion list (argic /
ferralic / petroplinthic / pisoplinthic / plinthic / spodic) as
"<= 100 cm unless buried below 50 cm". The earlier
implementation excluded an Andosol whenever any of those
diagnostics passed anywhere in the profile, including on layers
starting deeper than 50 cm – which mis-fires on AfSP Andosol
references like CM W3_0047, where an argic layer at
56-72 cm wrongly excluded the andic surface stack. v0.9.85
restricts the exclusion check to layers starting <= 50 cm:
a buried argic / ferralic / plinthic / spodic at deeper levels no
longer disqualifies the surface andic stack from Andosol.