128 Layer limit superior / inferior

The upper (lower) limit of the layer depth (in cm).

The limit between the organic and mineral layer corresponds to 0 cm.

For organic layers (OL, OF, OH, OFH, Hf, Hfs, Hs), the limits are negative values.

For mineral layers (M05, M01, M51, M12, M24, M48) the limits are positive numbers.