[Tagging] A name for stony ground?
dieterdreist at gmail.com
Thu Sep 1 22:44:17 BST 2011
2011/9/1 Johan Jönsson <johan.j at goteborg.cc>:
> Bryce Nesbitt <bryce2 at ...> writes:
> I have also looked at the UN-organization FAO that reasons about a scheme for
> tagging land cover...
in this doc they list general criteria for landcover classification:
"The reference classification should be:
* comprehensive, scientifically sound and practically oriented;
* meet the needs of a variety of users (neither single-project
oriented nor taking a sectoral approach); users can use just a sub-set
of the classification and develop from there according to their own
* potentially applicable as a common reference system, and facilitate
comparisons between classes derived from different classifications;
* be a flexible system, which can be used at different scales and at
different levels of detail allowing cross-reference of local and
regional with continental and global maps without loss of information;
* able to describe the complete range of land cover features (e.g.,
forest and cultivated areas as well as ice and bare land, etc.), with
clear class boundary definition that are unambiguous and unique;
* adapted to fully describe the whole variety of land cover types with
the minimal set of classifiers necessary (the less classifiers used in
the definition, the less the error expected and the less time and
resources necessary for field validation); and
* based on a clear and systematic description of the class, where the
diagnostic criteria used to define a class must be clearly defined,
with pure land cover criteria distinct from environmental criteria
(e.g., climate, floristic and altitude), as the latter influence land
cover but are not inherent features."
It's indeed interesting how they do landcover, they work in 2 phases.
In the first phase they use 3 simple steps to differentiate.
1. "Primarily vegetated=yes/no" and a criterion for vegetated with at
least 4% vegetation cover for at least 2 months of the year.
this results in 2 classes, each of which is analyzed in a second step:
2. "Edaphic Condition=terrestrial/aquatic or regularly flooded"
aquatic includes marshes, swamps, bogs and all areas where water is
present for a substantial period regularly every year.
the 4 resulting classes are then divided by their
3. "artificiality of cover" in "Artificial/managed" and in "(Semi-)natural"
Those classes are then further refined in the second phase, when more
detailed landcover and environmental attributes like climate, erosion,
landform are added.
A scheme is here:
More information about the Tagging