Inventory Layer

The Inventory Layer file creates the initial inventory layer. The input_traza, input_SOC and the output_gcbm parameters define the Trazabilidad file where the land usage data is stored, the folder where the soil organic carbon data is stored and the folder of the output data respectively.

Apart from this, we define the inventory_year which denotes the initial year of model execution. The layer_traza and layer_SOC defines the land use data (Trazabilidad) and the Soil organic carbon data from FAO respectively.

We will be generating the inventory layer from the trazabilidad file by reading the same and optionally filtering the database to accommodate the polygons that were forest at a particular point in the time-series data. Further, the classifiers are assigned, which includes the Tipofor classifier, Forest structure classifier and Origin classifier.

The Tipofor classifier gets the forest types from the 1997 map and assigns the “Bosque Mixto” and “Matorral Arborescente” forest type from the T1 column. Polygons that are “non forest” will be left as No Forestal.

traza$Tipofor <- as.character(traza$T_F_97)

traza$Tipofor <- ifelse(traza$T1 == "0403", "Bosque Mixto", as.character(traza$Tipofor))

traza$Tipofor <- ifelse(traza$T1 == "0304", "Matorral Arborescente", as.character(traza$Tipofor))

traza$Tipofor <- ifelse($Tipofor), "No forestal", as.character(traza$Tipofor))

The Forest structure classifier follows the same steps, albeit we add a filter to leave only 4 columns. The origin classifier is used to distinguish between forests that comes from the initial inventory (bosque inicial) for accounting purposes.

Initially, the shapefile is reprojected and the SOC is calculated by calculating the mean of each polygon. Later the age and SOC is determined by reprojecting the input shapefile to latitude and longitude and calculating the mean data in each polygon. If the GCBM detects a SOC greater than 0 in a forest pixel it will not work.

Finally, the historic and current land use assumptions are made, taking into account, FL if it is a native forest, and CL if not. The shapefile is written and the inventory layer is published in the Output_files directory.