Morphometric analysis of watersheds is a crucial component in hydrology and water resource management. Traditionally, this process required a significant time investment and was prone to human error. The “Watershed Morphometric Analysis” tool for QGIS simplifies this process, offering a comprehensive and accurate analysis in a matter of seconds.
Tool Description
“Watershed Morphometric Analysis” is a specialized QGIS plugin that automates the calculation of over 30 essential morphometric parameters. This tool covers everything from basic measurements like watershed area to complex indices such as shape factor and time of concentration.
Prerequisites
To effectively use this tool (you can download the data here), the following data is necessary:
- Polygon layer representing the watershed boundary.
- Line layer of the drainage network, which must include a field with the Strahler classification. This field is essential for various morphometric calculations.
- Digital Elevation Model (DEM) of the study area.
Installation Process
- Open QGIS.
- Navigate to “Plugins” > “Manage and Install Plugins”.
- In the search bar, enter “ArcGeek Calculator”.
- Select the plugin and proceed with the installation.
User Guide
- Data Preparation:
- Ensure that the river layer contains a field with the Strahler classification. This information is critical for the analysis.
- Verify that all layers (watershed, rivers, and DEM) are in the same coordinate system.
- Tool Execution:
- Access “ArcGeek Calculator” > “Watershed Morphometric Analysis” in the “Plugins” menu bar of QGIS.
- Parameter Configuration:
- Select the watershed layer.
- Choose the drainage network layer.
- Specify the field containing the Strahler classification.
- Select the corresponding DEM.
- Determine the watershed outlet point on the map.
- Initiate the analysis.
- Results Review:
- The tool will generate a detailed report with all calculated parameters in less than a minute.
Calculated Parameters
The tool provides a comprehensive analysis, including:
- Watershed area and perimeter
- Watershed length and width
- Form factor and elongation ratio
- Drainage density and stream frequency
- Time of concentration (multiple methods)
- Ruggedness number and compactness coefficient
- Bifurcation ratio and drainage texture
Advantages of Using the Tool
- Efficiency: Drastically reduces analysis time.
- Precision: Minimizes calculation errors.
- Consistency: Ensures uniform results across all analyses.
- Integration: Works seamlessly within the QGIS environment.
- Versatility: Applicable in hydrology, geomorphology, environmental engineering, and related disciplines.
