Getting Started with the Acadian Variant (ACD)

OSM-ACD Input Tables

To run the model for your plots or stands, you need two input tables (OSM_StandList & OSM_TreeList) in an Access database.

 

The following provides guidance on how to properly setup these tables for use in New Brunswick.

 

For detailed input table guidance, see Acadian Input Tables.

OSM_StandList Table

Important columns for correct calibration of OSM-ACD in NB:

§  SurveyID [CLI plot number; numeric or text]

§  SurveyYear [year of field collection; optional;  integer]

§  SurveyAge [years post stand establishment (clearcut); applicable for managed stands; integer]

§  BGI [site index; numeric]

·         BGI = Biomass Growth Index (Hennigar et al. 2016)

·         www.forusresearch.com\bgi.php

·         Intersect the NB raster with your plot coordinates

§  Zone [“NB” for all plots; this turns on the NB tree models; text]

§  Management [five management types; text]

·         “None” – no recent management

·         PartialCut” – recently partial cut (<20 years ago)

·         “Clearcut” – recently clearcut or overstory removal (< 20 years ago)

·         “PCT” – has been pre-commercially thinned

·         “Plant” – has been planted

·         Commercially thinned “PCT” or “Planted” stands are still considered “PCT” or “Planted”, respectively

 

See additional optional OSM_StandList columns in Acadian Input Tables

OSM_TreeList Table

Important columns for correct calibration of OSM-ACD in NB:

§  SurveyID [CLI plot number; text or integer]

§  TreeID [Optional; integer]

§  Species [USDA Plant Code - see species lookup table in OSM-Acadian documentation; text]

§  DBH [diameter in centimeters outside-bark at 1.3 m from ground]

§  HT [total tree height; meters; null if not available]

§  CR [tree crown ratio; 0-1; null if not available]

§  Stems [tree expansion factor; # trees/ha this individual represents]

§  Weight [tree height subsample relative weight for local height model calibration; null if no height sampled]

 

See additional optional OSM_TreeList columns in Acadian Input Tables

OSM_TreeList.Weight

Weights used in OSM_TreeList to properly calculate estimates of Lorey’s height for alternative plot designs (fixed area vs. angle gauge), which is used during height predication. Weights are also used to ‘weight’ self-calibration of the height model with height observation samples, if present in the tree list. See weight column in Acadian Input Tables and also additional guidance on how to set weight values in OSM.Simualtion.Model.HeightModel.

 

OSM-ACD Execution

See OSM download package for DOS examples and HTML help files on running the software.

OSM uses a custom command language that is written by the user into a text file to tell OSM what you want it to do. The text file is submitted as a file path argument to the OSM executable (OSM.ConsoleApp.exe) through a DOS batch file. The command language uses indenting (similar to python) to access OSM command objects and properties hierarchically.

 

The example below demonstrates all the commands needed to load OSM_STANDLIST and OSM_TREELIST, run the first simulation cycle (which includes prediction of missing tree heights at the start of the simulation cycle), and output of the resulting tree lists for every plot into a CSV text file. It is very important to respect the number of TAB characters when indenting commands. You can also use a single space instead of a TAB, but you cannot mix tabs and spaces.

 

 

SIMULATION

      YEARS 1

      YPC 1

 

INPUTS.Source “C:\...\Plots.accdb”

 

#Turn off snag initialization and tracking

SIMULATION.Model.SnagModel.MinDBH 999

 

OUTPUTS

      TreeList

            FilePath "C:\...\TreeListReport.csv"

            SetStandColumns SurveyID Cycle Year

            SetTreeColumns TreeID Species DBH HT Stems

 

SIMULATE

 

 

Copy the OSM code above into a new text file (MyOSM.osmc).

 

In a Windows DOS batch file (OSM.bat) call the OSM executable (OSM.ConsoleApp.exe) with the following two arguments: 1) the Variant code (in this case ‘Acadian’) and 2) the command file with the file path as shown below:

 

                Call C:\...\OSM.ConsoleApp.exe Acadian C:\...\MyOSM.osmc

                Pause

 

Avoid spaces in your directory names, or surround path names with double quotes.

Double click the OSM.bat file and OSM will load the Acadian Variant runtime and process commands in MyOSM.osmc. Tree-level records and predictions for each simulation cycle, and for each plot in OSM-StandList will be reported to TreeListReport.csv.

 

Change command YPC to 5 and YEARS to 100 and the simulation will run for 100 years in iterations of 5 years per simulation cycle. Tree lists for each cycle will be append to TreeListReport.csv.

Next Steps

Once you master above, start to learn other OSM commands to simulate harvest, disturbances, climate change, customize outputs, and even locally calibrate the model.

The basic execution procedure described above can be automated to allow for thousands of stands to be simulated. A good example of this the FORUS Simulation Framework application developed by FORUS Research. It can automatically write OSM commands, oversee execution and database management, and calculate a massive range of alternative stand-level yield outputs from OSM tree list outputs.