Kategorier: Alle

af Amanda M 25 dage siden

9

Methods for delination

The process of delineating watersheds using SAGA GIS involves several key steps. First, a Digital Elevation Model (DEM) with a 10-meter resolution is used as the input. Sinks in the DEM are removed to create a filled DEM, which is then used to generate a flow direction raster employing the D8 method.

Methods for delination

In SAGA GIS the interactive Upslope Area tool

This is the case for this lab report. There are three points; the two outlets and the guage

In SAGA GIS the Channel Network toool is used

In SAGA GIS this is one of the outputs of the Channel Network tool

In SAGA GIS vectorize the watershed raster

In SAGA GIS the Flow Accumulation (Top-Down) tool is used which takes the depression voided DEM as input

In SAGA GIS the Fill SInk (Win Liu) tool is used

In this case, through trial and error, a value of 550,000 is used because its output appears to match the real streams adequately.

Derive a watershed for each point

Modify the watershed as need

Done

Methods for delination

Input: Digital Elevation Model (10m resolution)

Remove sinks. Create a filled dem
Make a flow direction raster using the filled dem and the D8 method

Make a flow accumulation raster

Make a stream network based on a chosen initiation threshold.

Are pour points provided?

True

Create a stream link raster

Derive a watershed for each stream section