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Land Cover Classification System v. 3 (or Land Cover Meta Language) design criteria

A classification process aims at structuring a specific knowledge domain in order to create consistency and stability in communication between individuals. In other terms classification is a way to create order and stability for knowledge communication.

The LCML is an attempt to classify the "real world features" (specifically Land Cover features) with a very simple groups of elements arranged in different ways that act as building blocks to describe the more complex semantic in any separate application ontology (legends).

LCML should be able to work as "boundary object" to mediate and support negotiations of different ways to represent Land Cover around which similarities and differences can be understood and expressed. This means that classes derived by LCML can be customized to user requirements but must have common identities between users.
The most distinctive theoretical characteristics of LCML are:
  • Essential elements of the language allowing to balance the goal of a global standardization of Land Cover terms with the need for enough detail of Land Cover description to ensure practical applicability. In other words the "elements' must be the as much as possible limited in number , representing very well accepted terms and being able to represent also very distinctive land cover situations.
  • Reduction as much as possible of complex descriptions and definitions.
  • Fundamental idea of the language is that a predefined set of land cover basic elements (called BASIC OBJECTS) enriched on their semantic significance with external qualities and attributes and arranged in different types of strata can be used to describe a wide variety of distinctive and detailed land cover situations.
UML representation of LCML
The main advantage of LCML is that a UML diagram, that is a visual representation, is easier to read and understand in non-technical contexts rather than the mathematical formalisation used for LCCS. Moreover, the object-oriented structure of UML is a basis for implementation in languages like JAVA or C++.

The final version of the LCML is then an easy to read picture of the classification model without any constraints between different elements composing a Land Cover Class.

XML schema definition for LCML
In order to use the LCML as a reference for the implementation of land cover classification software, it is necessary to translate the UML concept model to a computer oriented format. The XML Schema language from WC3 has been chosen for its immediate compliance with object-oriented structures, for its worldwide diffusion and for its soundness in terms of documentation resources, development and support.

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