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A catchment is an area of land that drains water and other substances to a common low point or outlet such as a river or wetland. Catchments are used as building blocks to construct ecological benchmarks.
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| Fig 1. Catchments |
A catchment is an area of land that drains surface water and precipitation to a common low point or outlet such as a river or wetland. Many small catchments combine to make up larger watersheds. For this dataset, we designed catchments to represent approximate drainage areas for individual stream segments. These catchments were designed specifically to serve as the spatial units for the construction of ecological benchmarks with the Benchmark Builder.
The catchment dataset was created in ESRI ArcGIS 9.3 using the Atlas of Canada 1:1,000,000 Drainage Network Skeleton Version 6 and the Canada 3D Digital Elevation Model (1:250,000).The Drainage Network Skeleton is comprised of arcs representing rivers and flow lines through lakes and includes stream-ordering attributes that are queried by the Benchmark Builder to determine the relative upstream and downstream position of each arc. We refer to these arcs collectively as the stream network. Each catchment contains a stream arc into which the surface water of the catchment drains. Catchments in the boreal range in size from 1 km2 to 1,987km2 (mean 30 km2, median 13.5 km2).
For more information on how we created the catchments and associated attributes, download the catchments manual.
A draft version of this dataset is currently under review and will be made available on databasin.org once the review process is complete.
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