On 27-Oct-17 06:52 PM, Tomas Straupis wrote:
Some info on how/why forest/wood tagging is used in Lithuania. I will
not give specific tags (forest vs wood, landuse vs natural etc),
because in my opinion that is a secondary issue. Let's say we have
tags F1 and F2.
F1 is for general forests. Those are the ones depicted on small scale
maps (full country/region).
Topology: They cannot overlap with other general landuse polygons:
water, reservoirs, riverbanks, meadows, scrub, sand, residential,
commercial, industrial zones etc.
Usage:
cartography: when generating small scale map we get a topologically
correct mosaic - non overlapping polygons - we do not have to worry
about overlapping polygons, draw order.
statistics: used to calculate percentage of forest coverage for a region
F2 is for small wooded areas INSIDE other polygons, usually inside
residential, commercial, industrial zones.
Topology: They MUST be above (fully inside) residential, commercial or
industrial polygon. If the F2 forest area is too large to be included
in say residential area - change it to F1.
Usage:
cartography: ignored for small scale maps. for large scale maps
(detailed small area) they are drawn on top of residential, commercial
and industrial areas.
statistics: ignored when calculating percentage of forest coverage.
This approach ignores utility as such (managed, non managed, natural,
left for full nature cycles as mention in Oleksiy's post). This
information could be added as a sub-tag if needed for some thematic
maps or specific statistical calculations.
What I'm saying is that maybe we should:
1. first decide the PURPOSES of having "tree cluster" polygons tagged
separately.
2. Then PRIORITISE the purposes (based on ACTUAL usage ignoring all
"it could theoretically be used to/for...")
3. and then decide which info goes to primary tag, which goes to
secondary tag(s).
4. And only THEN decide on actual tags (keys, values).
Doing it the other way round will take us back to this forest
discussion as it has been here for the last ten years like discussing
what the words "forest", "wood", "natural", "landuse", "landcover"
etc. actually mean.
In; F1 there are the words "general landuse polygons"
F2 there are the words "residential, commercial, industrial zones" that clearly
imply land use.
So your discussion is clearly about land use? Fine - that is ok.
I have an area that is used for recreation - picnics, walks, etc. It is a designated
"National Park".
So human land use is 'recreation'. There are native animals in there .. but the
plan of management is primarily for 'recreation' and has been for many decades.
Some of the area is grassed, some trees ... but the human use of the land is
not 'grass' nor 'trees', but 'picnic', 'walks' and 'peace and quite'.
At the moment there is no declared landuse tag on this area, it does have a
admin boundary for the National Park, which could also in this case be used for
the land use. It does have separately tagged land covers of paved, unpaved,
trees, grass and water. But the single land use should be recreation.
As the 'use' is separate from 'cover' these things should be considered
separately.
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