The Coastal Ecosystem Mapping and Media Viability Project

Figure 25. Polygon shapefile of mangrove tree features derived from the ISO classification output after a reclassification of the raster dataset. To clean the data, the area of each feature is calculated and small polygons that are non-tree features such as shrubs are selected and deleted in the editor menu.

Photo 4. Polygon shapefile of mangrove tree features derived from the ISO classification output after a reclassification of the raster dataset. To clean the data, the area of each feature is calculated and small polygons that are non-tree features such as shrubs are selected and deleted in the editor menu. After this process, it is possible to manually edit the polygon to delete any non-tree features from the mangrove tree polygon shapefile, or to slightly buffer and merge the mangrove tree polygon shapefile to join each small clusters of “tree features” in the image. Determining Tree Height We use the Digital Surface Model (DSM) output from Pix4D that shows change in elevation, including tree features, and a Digital Terrain Model (DTM) that shows change in terrain elevation, excluding tree features, to estimate mangrove trees mean heights in our study area (figure 20).

Figure 11. Figure 26. Explanation figure to differentiate the Digital Surface Model (DSM) that shows change in elevation/pixel including features such as trees from the Digital Terrain Model (DTM) that shows change in elevation/pixel at the ground level, excluding above ground features.

The Coastal Ecosystem Mapping and Media Viability Project

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