<div dir="ltr"><div dir="ltr"><br></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Jul 10, 2020 at 8:19 AM Warin <<a href="mailto:61sundowner@gmail.com">61sundowner@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
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<div>On 10/7/20 9:30 pm, Peter Elderson
wrote:<br>
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<div dir="ltr">Looks like humus is a component of soil. So I think
soil covers it, being a top layer consisting of mixed organic
and mineral matter.
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<div>To me it is hard to imagine an area as permanently
natural=bare_soil. Wouldn't there always be some kind of
vegetation within a year? <br>
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<p>Not always. <br>
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<p>Sorry to say but some soils have been so polluted combined with
the resulting soil erosion vegetation has taken some decades to
come back. <br>
</p>
<p>See <a href="https://en.wikipedia.org/wiki/Queenstown,_Tasmania#Ecology" target="_blank">https://en.wikipedia.org/wiki/Queenstown,_Tasmania#Ecology</a></p></div></blockquote><div><br></div><div>I'd imagine that pollution and erosion would result in a surface of mineral, rather than organic soil; hence the land cover would be clay, sand, scree, or bare_rock, depending on the particle size. Even the article you cite mentions areas eroded to bare rock. These values are all available for tagging a mineral surface.</div><div><br></div><div> </div></div><div><br></div>-- <br><div dir="ltr" class="gmail_signature">73 de ke9tv/2, Kevin</div></div>