m price schrieb:
>
>
> Keith J Matthews wrote:
>
> > This is a system I've been using for about twelve years; it seems to work
> > reasonably well, though you still need to use a bit of "skill and
> judgement".
> >
>
> This system is similar to the US Dept. of Ag. soil manual descriptors
> andseems to work pretty
> well, but ultimately soil description is a subjective
> process---the descriptors are an attempt to standardize it. I've found
> that the most reliable way to gather soil data is to have samples taken
> from the field and assign one person to perform the soil descriptions.
> All samples can then be examined under the same conditions by the
> same eye, providing controlled descriptions, or at least some consistency
> in interpretation, especially with the Munsell.
>
good idea
> > It raises questions about why we do this in the first place!
>
> Part of the soil description includes characteristics of horizon
> boundaries,which can tell you
> about depositional history, site formation processes,
> potential ag use, matrix origin, etc. The same goes for what's in the matrix,
> i.e. clays, sand, organics, rounded pebbles v. angular gravel, etc. At the
> very least, you should be able to determine what soil series you've got
> on your hands so you can consult your local soil survey to read more about
> what you might be dealing with. Hopefully you've done this before entering
> the field.
>
trouble is when you try to talk to a real pedologist about what you're doing and
realize the 2 of you just aren't talking the same language...
> The bottom line is that you need a standardized descriptor to back up what
> you can see with your eyes and feel with your trowel in the field. This is
> Science, after all.
>
> For more on the description process, as well as interpretations of what all
> that
> mud squishing in your fingers might mean, try:
>
> Soil Survey Staff
> 1975 _Soil Taxonomy_. USDA Agriculture Handbook 436.
> .
> It's a page turner.
>
> mp
will try to get a copy - thanx/dank u well
lazy bastard finally set up a website:
http://home.t-online.de/home/gcarver/
geoff carver
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