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GLC2000 presents 21 land cover classes, following FAO LCCS, for global mapping. Includes mandatory classifiers like cropland and natural vegetation. Proposals for refining legend and mapping criteria. Discussion on additional classes and legends.
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Main characteristics of GLC 2000 classification • No pre-defined class names but land cover is described by a set of classifiers and attributes based on the FAO LCCS: LCCS definitions and thresholds accepted 2. Land cover should be described at any geographical scale at the best possible detail 3. Detail of a legend depends on the • information obtainable from SPOT VEGETATION 2000 data • capability to map a class consistently • auxiliary map or information sources • Regional and sub-regional legends are developed - following a Minimum set of mandatory classifiers The global legend will be achieved by grouping of regional classifiers and attributes
Rationale for the approach • regional or sub-regional maps can be produced with detailed legend • legends can be formed according to user needs and purpose • no need to force a regional land cover in a predefined global class name • links possible to the national and local data, if all coded with LCCS • follow a standardized classification approach • enlarge the potential applications and user group • address different geographical scale • Requirement : • mandatory minimum set of land cover classifiers to be followed in order to achieve a uniform and consistent global map
Minimum Requirements : ‘Cropland’ (terrestrial) & Bare Areas ‘Cultivated and Managed Terrestrial Areas’ • Surface aspect • Consolidated • Bare rock • Hardpan • Unconsolidated • Bare Soil • Loose and shifting sand
GLC2000 - Global Land Cover Classes 21 land cover classes are presently proposed for display at the global level
Example of aggregating regional classes to global legend: South-Asia
Issues to be decided • Proposal: Display at the global level the two classes for broadleaved deciduous tree cover • a) closed: >>> forest type • b)open: >>>> open forests & woodland formations • Rationale: • display large tropical and sub-tropical dry forest-woodland formations in Africa, SE-Asia & S-America separate from the mainly closed temperate and boreal deciduous forests • some Mediterranean forests would be in the open class • the open boreal coniferous and mixed forests are not concerned by this separation.
Issues to be decided • Proposal: • Map the swamp forests together with the mangrove forests as • regularly flooded • Rationale: • more consistent with LCCS concept (than only mangroves) • represent large areas of swamp forests in C-Africa, S-America, SE-Asia • differentiation between mangroves and swamp forest is clear because of the location of mangroves at the coast • check whether consistently and important in other regions
Issues to be decided • Map burnt areas as a separate class • Rationale: No decision can be made on whether to assign these areas in the boreal or humid tropical zone to trees, shrubs, grass or mixtures • Proposal: • I. Burning is an annual and regular process • Map burnt areas along with the non-burnt class: burnt savannah (herbaceous cover) remains herbaceous cover • II. Burning is a single event or occurring in long intervals • If post-fire vegetation unknown > assign to shrub or sparse vegetation • introduce a class ‘natural vegetation, burnt’?
Issues to be decided Proposal: Make a difference between natural grassland and pasture at the global level?
Issues to be decided Mosaics: Are the present mosaic classes appropriate? Mosaic Tree cover & other natural vegetation Mosaic Cropland & Tree cover Mosaic Cropland & Other natural vegetation & Trees
Issues to be decided Mixed forests: Do we need more than one class of mixed forest? Mixed needle-leaved and broadleaved forests Mixed evergreen and deciduous forest Mixed evergreen and deciduous needle-leaved forest
Issues to be decided • What to display on global legend on global map • Display LCCS class name Tree cover, broadleaved, deciduous, open • Display a user class names? Open deciduous forests and woodlands • Display additional fields • with regional user class names? • Global: Tree cover, broadleaved, deciduous, open • Africa: Miombo • S-America: Catingas • SE-Asia: Dry Dipterocarp forest • For regional legends on regional maps • Regional LCCS class + regional user name • For the digital data set • Global LCCS class name • + Regional LCCS class name • + Regional user name • + full LCCS Code