Return the horizon top depths from a call to get.increase.matrix()

get.increase.depths performs the conversion of the square matrix output of get.increase.matrix back to horizon top depth for where criteria were met.

get.increase.depths(p, attr, threshold.fun, vertical.distance)

Arguments

p

a SoilProfileCollection, containing a single profile

attr

horizon attribute name to get the "increase" of

threshold.fun

a function that returns the threshold (as a function of attr); may return a constant single value

vertical.distance

the vertical distance (determined from difference SPC top depth variable) within which increase must be met

Value

Returns a numeric vector of depths where the increase requirement is met. For the argillic, the first is the one of interest.

get.increase.depths converts to horizon dop depth by using above matrix output to determine depths where increase is met.

Details

Note that the threshold.fun result is allowed to contain NA, but that will result in no output for affected cells.

See also

getArgillicBounds, crit.clay.argillic

Author

Andrew Gene Brown

Examples

data(sp1, package = 'aqp')
depths(sp1) <- id ~ top + bottom
site(sp1) <- ~ group

p <- sp1[1]
attr <- 'prop' # clay contents
foo <- get.increase.depths(p, threshold.fun = crit.clay.argillic,
                           attr = attr, vertical.distance = 30)
foo
#> [1] 49 57