5.0 Map Legends

A map legend provides a summarized description of all map unit components and map symbols, together with other supporting information including survey objectives, survey intensity, location, field sampling, other data sources, aerial photograph reference numbers, and map credits.

The recommended type of legend for terrestrial ecosystem maps has an open format and involves a list of ecosystem units and symbols that may be mapped as simple or compound map units. A large number of unique map units can potentially result from this open legend format. Mitchell et al., (1989) present further details on open and closed legend formats.

As a minimum, the items described in Table 5.1 should be included in all ecosystem map legends. Figure 5.1 presents an example. The specific layout and the amount of space allocated to each category may vary by project, and other categories may be added as required (e.g., interpretive information for ecosystem units). It is important to keep in mind that the map legend should contain only summary information that is generally expanded in the report (called an "expanded legend") accompanying the map.

Most agencies have specific requirements as to what must be in the expanded legend. Generally, an expanded legend will contain descriptive information for each mapped ecosystem. This includes the site series name, all related coding, a description of typical environmental characteristics, and the features that characterize atypical site series as identified by the site modifiers. The expanded legend will also describe the vegetation related to structural stages and any important associated features. Presentation of the information can be in a variety of formats. Examples of expanded legends can be found on the TEM website (see Appendix B).

Table 5.1

Minimum data to be included on map legends

Item	Minimum Requirements	Comments
1. Title	Include:	Example: Ecosystem Units of the Date Creek Research Area, Prince Rupert Forest Region, portion of map sheet 93M 009 (1:20 000), February 1992
	Study area name Map sheet number/s (NTS, BCGS) Map scale Date

2. Introduction	Include:	Sampling followed Survey Intensity Level 4 (RIC 1995).
	Objectives of the mapping project (including interpretations to be supported by the map) Study area Mapping standards (include reference to this document and survey intensity level)
3. Map Label Format	Provide example labels of ecosection, biogeoclimatic, and ecosystem units components, clearly indicated
4. Map Boundaries	Provide examples of all line types used to delineate polygons (see section 3.5), including study area boundary and sample plot locations
5. Ecoregion Units	List all applicable ecosections or ecoregions and their codes
6. Biogeo-climatic Units	List all applicable biogeoclimatic units and their codes
7. Site Units	Provide a description of site units, including site series names, two-letter codes and site series numbers, typical situations and moisture regime, assumed site modifiers and mapped site modifiers.	Detailed descriptions of site units should be provided in a separate report
8. Site Modifiers	List mapped site modifier and code	Only modifiers used in the mapping project need to be listed
9. Structural Stages and Modifiers	List structural stages, structural stage modifiers and codes	List and describe all structural stages, including the age criteria specific to each biogeoclimatic subzone (see Table 3.3.)
10. Data Sources	Include lists of all data sources in the project:
	aerial photos (year, scale, all photo numbers, colour or black and white) all previously available data and maps, such as forest cover, satellite imagery, base maps, etc. percent polygons and/or ha per inspection checked number and type of samples
11. Credits	Include: names of all mappers and field personnel name of project supervisor names of correlators and reviewers co-ordinating and funding agencies GIS personnel
12. Citation	Provide the citation as it should be referenced in other reports.

Figure 5.1 Example of Map Legend

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