Section 1	Identification Information
Originator	World Wildlife Fund Canada
Title	Ecological Classifications for Lake Superior
Abstract	This data set represents a coarse-level hierarchical terrestrial ecosystem classification based on climate, soil, and landform information. This data was taken from the World Wildlife Fund of Canada's ECS coverage. Work on classifying marine and aquatic systems for the purposes of planning an ecologically representative system of protected areas is still in its infancy. WWF Canada is currently finalizing a classification system for protected areas planning, building on work done to date in Canada. At present, preliminary supporting principles and a methodology for mapping marine and aquatic natural regions and identifying seascapes (the analogues of enduring features) have been drafted. Three case studies have recently been completed which apply the methodology, consisting of one freshwater and two marine studies of the same area: Lake Superior (Geomatics 1997a) and the Scotian Shelf (Geomatics 1997b, Day and Lavoie 1998). WWF Canada circulated the results of these case studies for peer review. The following is a preliminary outline of the work completed to date for Lake Superior, presented in as much detail as is possible at this early stage. There have been few attempts at defining natural regions and seascapes for lake systems. To date those that have been developed are principally descriptive, based on legend building using key characteristics of the lake or river system and fitting within an existing terrestrial system. Examples include the shoreline mapping component of the Ontario Land Inventory developed in the late 1960s (Richards et al. 1979) and the land/water integration approach developed by the Canada Committee on Ecological Land Classification (CCELC 1977). Neither of these build a fully hierarchical classification system based principally on inherent properties of the aquatic ecosystem. As a result, Geomatics International (1997a) has developed a preliminary hierarchical classification system from first principals. WWF in consultation with Dr. John Roff subsequently altered the original hierarchy to reflect further insight into lake classification. This classification forms the basis to determine representivity on which to undertake a protected areas gap analysis. The classification system assumes the availability of direct or surrogate data relating to each of the preferred factors identified in the hierarchy. For the Lake Superior case study, spatial frameworks were generated using enduring factors which were equivalent to ecoregions and ecodistricts. This has been completed in the form of Lake Superior natural regions and seascapes, respectively. These are illustrated in the attached maps. The work was completed using several data layers within ARC/INFO GIS. The data employed are the most current and best available to the authors and are representative at scales ranging from 1:250 000 through about 1:5 000 000. Ecoregions, in the terrestrial analogue, are defined as areas in which biological and edaphic responses can be differentiated at scales of about 1:1 million on the basis of climate, principally temperature and precipitation. Precipitation does not apply to the freshwater environment and we do not currently have sufficient data to sub-divide ecoprovinces based on temperature regimes (although this may be possible using satellite imagery). In our view, the closest analogues to climatic factors at this scale for the lacustrine environment relate principally to thermal properties (warm water, cold water and dimictic lakes) and light penetration. The most useful surrogate variable for distinguishing light penetration for entire lakes at this scale of the hierarchy is depth. The thermal nature of a lake and the presence of a thermocline is an important element of species segregation and resource partitioning. Light provides the energy for photosynthesis and primary production in most aquatic systems. Because light penetration is rapidly attenuated with depth and turbidity, the photic, dysphotic and aphotic zones are real functional zones limiting biological communities. Light penetration and turbidity are important determinants of submergent vegetation and are correlated with exposure and suspended particle size. For mapping purposes, we propose the use of 20 m depth as an average lake-wide class limit for the extent of the photic zone. Because lakes occur in confined-basins, their shape and gross bottom topography control many limnological processes, including those resulting from interactions with macro climatic regimes. For example, the presence of deep basins and shallow shelves as well as their orientation relative to major wind systems are extremely significant in patterns of freeze over and ice break up, and to water motion (stratification, upwellings, currents, etc.). These also relate to available energy in various portions of lakes, which in turn affect the size of particles deposited within the benthic regime. The influence of the surrounding landscape as a source of nutrients and other ionic inputs is an important factor affecting the distribution of energy sources within a lake. We have chosen to determine the morpho-edaphic index for sub-lake basins based on the assumption that surface currents will concentrate terrestrial nutrient inputs disproportionately across the lake. The use of topography and surface currents at this level in the hierarchy provides a consistent form of delineating sub-basins within a lake. The 3rd or 4th order watersheds are used to define the catchment area for that sub-basin.
Purpose	A base data layer.
Time Period of Content Date	1997
Currentness Reference	Geomatics lake classification system coverage
Progress	Complete
Maintenance and Update Frequency	As needed
Spatial Extent of Data	Lake Superior
Bounding Coordinates	-97.293 -81.564 49.255 41.573
Place Keywords	Lake Superior
Theme Keywords	enduring features, ecological, eco-regions, eco-districts
Theme Keyword Thesaurus	None
Access Constraints	None
Use Constraints	None
Contact Person Information	Mark White, Research Fellow Natural Resources Research Institute 5013 Miller Trunk Hwy Duluth, Minnesota 55811 Phone: (218)-720-2710 FAX: (218)-720-4328 E-mail: mwhite@sage.nrri.umn.edu
Browse Graphic File Name	none available
Browse Graphic File Description
Associated Data Sets
Section 2	Data Quality Information - - - - - - Go back to top
Attribute Accuracy	Contact WWF of Canada, http://www.wwfcanada.org/
Logical Consistency	Contact WWF of Canada, http://www.wwfcanada.org/
Completeness	Contact WWF of Canada, http://www.wwfcanada.org/
Horizontal Positional Accuracy	Contact WWF of Canada, http://www.wwfcanada.org/
Vertical Positional Accuracy	Not applicaple
Lineage	This data was taken from Canada's ecological classification coverage. It contains information for Lake Superior, clipped to the basin 50 km boundary.
Source Scale Denominator
Section 3	Spatial Data Organization Information - - - - - - Go back to top
Native Data Set Environment	UNIX-ARC/INFO Ver. 7.1.2, Sun Solaris operating system
Geographic Reference for Tabular Data	None
Spatial Object Type	Vector
Vendor Specific Object Types	Polygon, area
Tiling Scheme	Lake Superior-wide
Section 4	Spatial Reference Information - - - - - - Go back to top
Horizontal Coordinate Scheme	Geographic (Lat. Long.)
Ellipsoid	GRS80
Horizontal Datum	NAD83
Horizontal Units	Meters
Distance Resolution
Altitude Datum	Not applicable
Depth Datum	Not applicable
Map Projection Name	Albers Equal Area
Map Projection Parameters	Standard Parallel: 29.5 Standard Parallel: 45.5 Longitude Of Central Meridian: -96 Latitude Of Projection Origin: 23 False Easting: 0 False Northing: 0
Other Coordinate System's Definition	Planar Coordinate Encoding Method: Coordinate Pair Abscissa Resolution: 1 Ordinate Resolution: 1 Semi-Major Axis: 6378206.4 Denominator of Flattening Ratio: 294.98
Section 5	Entity and Attribute Information - - - - - - Go back to top
Entity and Attribute Overview	Entity and attribute information is self explanatory with a few exceptions: Enduring Feature - a landscape element or unit within a natural region characterized by relatively uniform origin of surficial material, texture of surficial material and topography - relief (Geomatics, 1993). Natural Region -(terrestrial) a geographical area characterized by broad similarities in climate, landform, geology and macro-vegetation type. Natural Region boundaries should be considered 'fuzzy lines' that broadly enclose characteristic biophysical features. See lineage and abstract.
Entity and Attribute Detailed Citation	None
Section 6	Distribution Information - - - - - - Go back to top
Publisher	Natural Resources Research Institute
Publication Date	Unpublished material
Contact Person Information	Gerald Sjerven, GIS Specialist Natural Resources Research Institute 5013 Miller Trunk Hwy Duluth, Minnesota 55811 Phone: (218)-720-4388 FAX: (218)-720-4328 E-mail: gsjerven@sage.nrri.umn.edu
Distributor's Data Set Identifier
Distribution Liability	No warranty expressed or implied is made regarding the accuracy or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. This disclaimer applies both to individual use of the data and aggregate use with other data. It is strongly recommended that careful attention be paid to the contents of the metadata file associated with these data. The University of Minnesota shall not be held liable for improper or incorrect use of the data described and/or contained herein.
Transfer Format Name	ARC/Info export format
Transfer Format Version Number
Transfer Size
Ordering Instructions
Online Linkage	Click here to download data. (See Ordering Instructions above for details.) By clicking here, you agree to the notice in "Distribution Liability" above.
Section 7	Metadata Reference Information - - - - - - Go back to top
Metadata Date	08/25/1999
Contact Person Information	Joel Nelson, GIS Intern Natural Resource Research Institute 5013 Miller Trunk Highway Duluth, Minnesota 55811 Phone: (218)-720-4254 FAX: (218)-720-4328 E-mail: jnelson@sage.nrri.umn.edu
Metadata Standard Name	Minnesota Geographic Metadata Guidelines
Metadata Standard Version	Datalogr 2.01
Metadata Standard Online Linkage	http://www.lmic.state.mn.us/gc/stds/metadata.htm

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