Module 7

River Freshie's Geomorphic Change

This is an analysis of the geomorphic change on the Freshie River in the Highlands of Scotland. For my analysis, I used Arc GIS Pro and performed the study without the Geomorphic Change Detection Software due to issues with the add-in, which prevented me from using it. 

I used the raster calculator to examine the differences between the DEMs. Then, I modified the range for all the results to match color symbology and range to make them comparable. 

Topographic comparisons from 2004 to 2007 looking for geomorphic change. The elevation change is shown with the range of +/- 2.5 m to make comparisons more effective. 

From this analysis we can see between each year where likely where deposition and erosion occurred.

Positive values (blue) = Surface increase/deposition

Negative values (red) = Surface decrease/erosion

Budget Segregation:

It is a way to quantify and classify various geomorphic changes occurring within a river system. For my budget segregation I focused on the changes that occurred from 2006 to 2007. 

The areas and volume of each geomorphic change are shown above. The geomorphic change was determined from the elevation difference raster and each year's DEM and Hillshade. The area was determined through each geomorphic change's attribute table, and the height was determined through the elevation difference raster formed from the DEMs

Bank Erosion:     Area: 1347m^2       Volume: 1482m^3

Channel Bed Lowering (degradation / incision):    Area: 1,651m^2      Volume: 1,099m^3

Channel Bed Rising (aggradation):    Area: 1,577m^2       Volume: 789m^3

Bar Development:    Area: 622m^2      Volume: 435m^3

From this analysis, I determined that Bank Erosion is more predominantly accruing than bar development. However, channel bed rising and lowering, there is more lowering occurring. From the analysis, we can deduce that between 2006 and 2007, more erosion and degradation occurred within the riverscape.