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Web Mapping Service
The Biodiversity & Environmental Resource Data System (BERDS) provides an Open GIS Consortium (OGC)-compliant Web Map Service (WMS) -- an Internet-based service designed to provide developers of on-line WMS compliant mapping tools access to the BERDS base spatial map layers. By using this service, scientists will have access to our most current and accurate base data for rendering customized maps. Access to this service is provided free of charge and does not require a contract or license agreement. WMS client software is required to render maps based on layers obtained from various server sources. To construct maps from WMS layers, WMS visualization software is also required.
Due to non-redistribution agreements in effect between the BERDS and our providers of thematic data, we presently can only offer our base information to the public.
WMS Map Layers:
There are individual base layers provided by this WMS.
The labels (names) of layers are provided in separate layers from their associated point locations (symbols). See GetCapabilities XML document below for details.
The following 29 national scale base layers are currently available through the BERDS WMS Server:
Climate
- Rainfall
Environmental
- Ecosystems (all)
- - Agricultural Uses
- - Forest Types
- - Mangroves
- - Marine Habitats
- - Wetlands
- Elevation
- Fire Risk
- Geology
- Land Use
- Hurricane Iris (yr 2001)
- Protected Areas
- - Biological Corridors (proposed)
- Soils
Freshwater:
- Rivers & Streams
- - Riverine Types
- Freshwater Salinity
- Freshwater Clarity
- Freshwater Sources
- Watersheds
- Groundwater Provinces
Other:
- UTM Map Grid
- LANDSAT (b & w; yr 1990)
- LANDSAT (colour; yr 1990)
People & Society:
- Districts
- Roads & Tracks
- Settlements & Population
- Biological Field Stations
- Exclusive Economic Zone
Specimens:
- Specimens
Service Requests
GetCapabilities
To obtain general information about this WMS and specific information about the available map layers, users should invoke the "GetCapabilities" request.
The response generated by "GetCapabilities" consists of an XML document to be displayed in your browser window. The form of the URL-encoded request is as follows:
http://www.biodiversity.bz/cgi-bin/mapserv?VERSION=1.1.0&request=GetCapabilities
&MAP=/Users/belize/biodiversity.bz/wms.map
The information contained within the resulting XML document will assist in selecting the layers desired for the creation of a map.
The unique layer names and their description as well as projection options are also provided in the XML document.
For a list of other available request parameters, please consult the following document: "OpenGIS® Web Map Server Interfaces Implementation Specification, Version 1.1.0" .
GetMap
The "GetMap" request is used to produce a map with BBMS base layers. Several parameters are required to form the URL request including:
VERSION, REQUEST, SRS, BBOX, WIDTH, HEIGHT, LAYERS, STYLES and FORMAT. For further information on these parameters and others,
please consult the on-line document entitled "OpenGIS® Web Map Server Interfaces Implementation Specification, Version 1.1.0".
The following URL-encoded string is an example of a functional GetMap request containing the above-mentioned parameters and their values: the "version" of WMS used is 1.1.0, the "request" is GetMap; the "SRS" (spatial reference system or projection) is expressed as EPSG:26716 (See the list in the Projections section that follows.); the "width" and "height" parameters specify a rectangle of pixels 500 by 500 in dimension, the value of "layers" is the name of the single layer displayed, district (to add additional layers, add a '&' and then 'layername' to the URL string (ex. &district&rainfall)); a null value is use for the "styles" parameter as the layer will be displayed using it's default styles; the map is the full path to our WMS map file (/Library/Apache2/htdocs/bbms/wms.map); and the "format" of the map image returned is PNG. (only PNG, JPG and WBMP supported)
http://www.biodiversity.bz/cgi-bin/mapserv?map=/Users/belize/biodiversity.bz/wms.map
&VERSION=1.1.1&REQUEST=GetMap&LAYERS=district&Width=500&Height=500&styles=&format=png
Please note that each parameter is separated by an "&" and values are assigned using the "=" sign.
Projections
When requesting a map from the BERDS WMS, users can obtain the resulting image in the following pre-defined EPSG (European Petroleum Survey Group) projection:
EPSG:26716 - [Equiv. to NAD 27 / UTM Zone 16N / Clarke 1866]
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