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| Standards: natural vegetation |
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Rules for (Semi-)Natural Classification
In the LCCS software, Life Form and Dominance are the two main
parameters used to classify Natural and Semi-Natural Vegetation.
These two main aspects are very important and must be carefully
determined as their selection will effect the possible available
choices during the classification process.
(For detailed information please refer to the
software manual).
The Life Form of a plant is generally defined by its physiognomic
aspect:
- Woody (Trees: height > 5 m; Shrubs: height < 5 m; Woody: height
between 2 and 7 m and no distinction into Trees or Shrubs)
- Herbaceous (Forbs and Graminoids)
- Lichens/Mosses
This general rule is subject to few exceptions, e.g.:
- a plant with a clear tree physiognomy can be classified as Trees
even if the Height is lower than 5 m but is more than 3 m. In this
case, a sub-condition of physiognomic aspect is added to the Height
condition
- plants essentially herbaceous but with a woody appearance (e.g.
bamboos and ferns) are classified as Trees if the height is more than
5 m, and as Shrubs if the height is less than 5 m.
A complete list of the exceptions is presented in the LCCS software
manual.
The Dominance is mainly defined by the uppermost canopy layer concept.
In fact, the dominant layer goes from Tree canopy to Shrub to
Herbaceous/ Forbs/Graminoids. This general rule is subject to the
‘sub-condition of Cover’ in which the layer selected must have either
Closed or Open cover. If the Life Form is Sparse, the Dominance goes to
another Life Form that has a Closed or Open cover.
The ‘Uppermost canopy’ concept can be better illustrated with an example:
what is normally called "Tree Savanna" consists of a closed herbaceous
vegetative cover that forms the main layer, with a second layer of sparse
trees projecting above. In this case, the use of the uppermost canopy
concept would designate the trees as a dominant layer over the herbaceous
layer. Because of the sub-condition of cover, sparse trees cannot be the
dominant Life Form with the presence of the closed herbaceous layer. This
concept must be carefully considered due to the in-built conditions in the
classification system. If the user starts with the wrong main Life Form,
e.g. sparse trees, the option to select closed herbaceous as second layer
will not be available because the system excludes any closed vegetation
layer if the main stratum is sparse.
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