Drainage basins

drainage basin

extent of land where all surface water from precipitation converges to a single discharge point

how do you delineate a drainage basin

using the contour elevation lines on a map

what are the nine components of a drainage basin

1. rides/divides

2. gullies

3. ephemeral channels

4. floodplains

5. perennial channels

6. soil

7. hillslopes

8. vegetation

9. aquifers

a drainage basin is a topographic region from which a stream/rive receives______

• runoff

• throughflow

• groundwater

runoff vs throughflow

runoff - surface processes

throughflow - infiltrated water that moves to river

how can drainage basins be identified on a map

by tracing a line along the highest elevations between two areas

what are the two longest rivers in NA and what watershed are they the backbone of

Mississippi and Missouri River

backbone of Mississippi watershed

how many major watersheds are in Alberta

7

what is Lethbridge’s main watershed and sub-basin

main watershed - S Sask river watershed

sub-basin - Oldman River Sub-basin

contrast homogeneous vs heterogeneous drainage basins

homogeneous - consistent and uniform properties throughout its area

heterogeneous - has properties that vary significantly in different locations

are small drainage basins typically homogeneous or heterogeneous? large drainage basins?

small - homogeneous

large - heterogeneous

what are independent variables that can change throughout a drainage basin

elevation, slope, vegetation, land use, climate