Final Project: Reproduction of Least Cost Model from Lyimo et al. (2023)

As mentioned in the previous post, I completed a final project for GEOG 0323 with classmate Alana Lutz. This can be described as a reproduction study in which we aimed to reproduce a least cost raster in R using the steps provided in a QGIS model. This model was created by Justin Lucas, another Middlebury student, in the summer of 2023 to serve an existing project concerning least cost pathway analysis in the Makuyuni Wildlife Corridor, Tanzania (Lyimo et al. 2023). The least cost raster in that study is intended to show the cost for a large mammal to travel across the land represented by a given pixel. Cost values are mediated by layers showing landcover, major and secondary roads, and buildings.

This project proved to be challenging work, but Alana and I were able to visualize a least cost raster. We found that the raster was not identical to the original raster due to an issue with the interaction of the computational environment and the buildings layer. Individually, I composed the various text-based sections of this personal version of the report (besides metadata on inputs, which was a joint task). Through our work, I learned much about the R packages sf, stars, raster, and tmap. Some common steps for the workflow included reading in shapefiles and .tif files, rasterization, reprojection, and reclassification. I did not have much previous experience with these packages nor the reproducible research compendium in which the report is housed, and I would therefore say that I have learned much from this project.

I acknowledge Alana and Dr. Holler, himself a co-author of Lyimo et al. (2023). I provided CRediT roles at the conclusion of the report linked below.

Here is a link to the full repository for the reproduction study.

Here is a link to the report.

Lyimo, E. H., Mayengo, G. M., Castico, D. J., Nguma, D., Martin, E. H., Hariohay, K. M., Kisingo, A. W., Lucas, J., Kimambo, N., & Holler, J. (2023). Makuyuni Wildlife Corridor: Analysis of the Effects of Socioecological Interactions and Changing Land Use on Movement Patterns of Large Mammal Species [Draft]. https://docs.google.com/document/d/1-RP3a5NUJcFMskoWzuZzMz4x-JI5DeKz/edit?usp=embed_facebook