This tool derives a channel network based on gridded digital elevation data.
Use the initiation options to determine under which conditions channels shall start.
| | Name | Type | Identifier | Description | Constraints |
|---|
| Input | Elevation | grid, input | ELEVATION | A grid that contains elevation data. | - |
| Flow Direction | grid, input, optional | SINKROUTE | An optional grid that provides information about flow directions.
Values between 1 to 8 force the flow of a cell to be given to one its adjacent neighbor cells (1->NE, 2->E, 3->SE, 4->S, 5->SW, 6->W, 7->NW, 8->N). In case of other values the algorithm will use its own routing scheme.
This option is in particular useful to supply the algorithm with routes that lead the flow through closed depression. | - |
| Initiation Grid | grid, input | INIT_GRID | Dependent on the chosen 'Initiation Type' and 'Initiation Threshold' the values of this grid control where a channel is initiated. | - |
| Divergence | grid, input, optional | DIV_GRID | Tracing: Convergence | - |
| Tracing: Weight | grid, input, optional | TRACE_WEIGHT | Tracing: Weight | - |
| Output | Channel Network | grid, output | CHNLNTWRK | If a cell is part of a channel its value equals the channel order. Otherwise the cell is marked as no-data. | - |
| Channel Direction | grid, output | CHNLROUTE | If a cell is part of a channel then its value shows the flow direction of the channel (1->NE, 2->E, 3->SE, 4->S, 5->SW, 6->W, 7->NW, 8->N). Otherwise the cell is marked as no-data. | - |
| Channel Network | shapes, output | SHAPES | This shapes layer will contain the resulting channel network in vector format (lines). | - |
| Options | Grid System | grid system | PARAMETERS_GRID_SYSTEM | - | - |
| Initiation Type | choice | INIT_METHOD | Options:
- Less than
- Equals
- Greater than
Controls under which condition a channel is initiated. | Available Choices:
[0] Less than
[1] Equals
[2] Greater than
Default: 2 |
| Initiation Threshold | floating point number | INIT_VALUE | Dependent on the chosen 'Initiation Grid' and 'Initiation Type' this value controls under which condition a channel is initiated. | Default: 0.000000 |
| Tracing: Max. Divergence | integer number | DIV_CELLS | Tracing: Stop after x cells with divergent flow | Minimum: 1
Default: 5 |
| Min. Segment Length | integer number | MINLEN | Minimum Segment Length (Cells) | Default: 10 |