Chapter 7 Spatial Models and GIS Integration
7.1 DEM processing
7.1.1 Learning Module 11
7.1.1.1 Objective:
Users will explore basic hydrological tools through the process of DEM preprocessing and defining stream networks for a watershed in the Fraser Experimental Forest in Colorado using Whitebox Tools for R. This exercise will also demonstrate methods for writing functions and efficiently handling multiple files simultaneously, including importing, processing, and exporting data within the context of Whitebox Tools for R.
Hydrological analysis preprocessing involves the use of digital elevation model (DEM) raster data to establish a watershed model and a simulation of surface hydrological processes. These steps enable us to quantify key parameters such as flow accumulation, stream network characteristics, and hydrological connectivity, which are essential for studying the dynamics of water movement within a landscape. Overall, preprocessing is the set of foundational steps in hydrological modeling and analysis.
Whitebox Tools is an advanced geospatial data analysis platform that can be used to perform common geographical information systems (GIS) analysis operations. This platform was developed with the Center for Hydrogeomatics in Guelph University so it is focused on hydrological analysis. With just a DEM, it allows us to produce a multitude of outputs that can be used for future analysis (Lindsay, 2016) doi:10.1016/j.cageo.2016.07.003). While we are demonstrating its use in R, these tools are also available in QGIS and Python platforms.