With a population exceeding 18 million and an area about the size of Ohio, Malawi’s natural areas are constantly threatened. In the area surrounding Thuma and Dedza-Salima Forest Reserves, charcoal burners have depleted forests as agriculture and settlements have expanded.
I made a series of maps for Wildlife Action Group and created the one below in conjunction with my cartography class. Inspired by the method outlined in Raposo et al. (2017) I used ArcGIS Model Builder to create a process that first simplified Landsat-derived landcover from either 11 (in 1990) or 15 (in 2010) classes to three classes: forest, agriculture, and everything else (grassland). The model then smoothed these classes by a series of shrinking, expanding, resampling, and finally creating a gradient that smoothly transitioned colors at the edges of each class. Afterwards, I used a combination of Photoshop and Illustrator to overlay the images onto the hillshades I created and arrange the final layout.
On the left is the distribution of the three classes in 1990 and the figure in the middle shows the same classes in 2010. On the far right, the base of the map is the same landcover classification seen in 2010, with the important addition of pink areas marking where there was forest in 1990 but not in 2010. I considered showing areas where forest had grown between 1990 and 2010, but the focus of the work was on highlighting areas of loss so felt it was best to not detract from that, despite clear signs of reforestation to the east of the reserve areas.
Photo: https://declass3.wordpress.com/2015/10/06/spotlight-on-africa-fast-fast-fire-is-ironically-saving-trees/