Landscape Table (SLC version 2.2)

Filename

{covername}.LAT

Description

The Landscape Table (LAT) contains attributes of the polygon, and attributes which apply to the entire landscape represented by that polygon. All areas are in hectares.

Contents

Field	Name	Width	Type
1	SL	6	I	(relate key)
2	LAND_AREA i	8	I	(area applicable to the COMPONENT table)
3 i	POLYGON_AREA i	8	I	(area of the entire polygon)
4	WATER_TOTAL	8	I	(area of total water including oceans)
5	WATER_FRESH	8	I	(area of total fresh water)
6	HYDRO_OCEAN	8	I	(area of ocean water shown in the HYDRO coverage)
7	HYDRO_FRESH	8	I	(area of fresh water shown in the HYDRO coverage)
8	SMALL_WATER	8	I	(area of small water bodies not shown in the HYDRO coverage)
9	SMALL_LAND	8	I	(area of small islands not shown in the HYDRO coverage)

Relationships

• A record in this file is unique with respect to SL.
• The SL field is used to relate (1:N) to the PAT.

Limitations

Table 1: Estimates of total fresh water and watershed surface areas (hectares).

SLC (v2.2 LAT)		Sebert and Munro, 1972	National Atlas	Statistics Canada
HYDRO_FRESH	60,599,667
SMALL_WATER	72,336,336
SMALL_LAND	333,867
WATER_FRESH	132,602,136	75,516,889	75,518,000	75,518,000
LAND_AREA	862,249,554
Drainage basin	994,851,690	998,802,900	999,540,000	997,061,000

The figures given for the SLC in Table 1 are based on the area of water found in the HYDRO coverage, as well as estimates of land and water which are not adequately represented by this coverage. The significant number of smaller lakes and islands that are not visible in the HYDRO coverage, are accounted for in the SMALL_WATER and SMALL_LAND estimates. These figures are under review and may be revised in the future.

There are only minor discrepancies between estimates of Canada's total drainage basin area shown in Table 1. In terms of fresh water however, the estimates by other agencies appear to ignore small water bodies (those not visible on the 1:250,000 scale topographic maps). These estimates are more comparable to the SLC's HYDRO_FRESH figures, which were obtained at a scale of 1:1,000,000.

Any prorating of these numbers should take into account the local variation in the density of small water bodies.

Background

The Landscape Attribute Table was developed to simplify the calculation of land and water areas for the SLC polygons, and remove ambiguities in the way water is represented in previous versions. This table was derived from the SLC and HYDRO coverages

References

Sebert, L.M. and M.R. Munro. 1972. Dimensions and areas of maps of the National Topographic System of Canada. Technical report no 72-1. Surveys and Mapping Branch, Department of Energy Mines and Resources, Ottawa, Ontario. Unpublished Manuscript.

effective version 2.2 Source: Peter Schut
Contact: Peter Schut