Biomass calculator
The Sustainable Sites Initiative (SITES) program promotes sustainable land development and management. The biomass evaluation provides an index score based on the selected biome, its density value, and the area percentage of the predicted post-value biomass against the existing biomass within a designated site area. The metric evaluates the density and distribution of vegetation types, such as trees, shrubs, grasslands, and wetlands.
The index assigns biomass density values to different vegetation zones and determines their percentage of the total site area. This allows designers to evaluate the existing biomass and plan for improvements that align with sustainability goals. A planned Biomass Density Index of 1 or more points associates with a credit for improved biomass in the project. The better the index, the higher the credit assigned.
To use the Biomass calculator:
Create the area for the project by adding a site model, or by drawing a simple polygon. Subtract any area that will serve as the tree canopy area.
The tree canopy area must be deducted from the area for underlying ground cover; no area can be calculated twice.
Attach the SITES Biomass Area record format to the boundary object, so that the Sustainability Dashboard can properly identify the object as total site area. Ensure that the entire area is assigned a vegetation type. The sustainability record formats are located in the Libraries\Defaults folder in the Record Formats\Sustainability file. See Attaching record formats to a symbol instance or object for information on how to attach records to objects.
Create the appropriate surface cover objects that make up the project. For a preliminary design, use geometry such as circles, polygons, and rectangles, and attach the Sites Biomass Index record format. For a more advanced design, use tools like the Hedgerow, Landscape Area, Hardscape, Plant, Existing Tree, and more. Vegetation types must be assigned to the entire area of the project to obtain the proposed value.
To open the SITES Biomass Index Editor dialog box, do one of the following:
For parametric objects created by Vectorworks tools, click Settings from the Object Info palette, and open the Sustainability pane. Click New Framework. For the Framework, select SITES Biomass Index, and then click Edit Framework.
For a hedgerow object, click Sustainability Framework from the Object Info palette. In the Hedgerow Sustainability Data dialog box, click New Framework. For the Framework, select BNG Sheet, and then click Edit Framework.
For geometry, click Edit Sustainability Data from the Data tab of the Object Info palette.
Use the Eyedropper tool to pick up data from one object with an attached record and drop it onto other, similar ones. For larger projects, save the sustainability settings of parametric objects as a style. You can also use the Data Manager to attach the record as a criteria-based object.
From the SITES Biomass Index Editor dialog box, specify the parameters related to the biomass area. Select a zone for each type of vegetation, and indicate whether it is planned or existing.
Click to show/hide the parameters.Click to show/hide the parameters.
|
Parameter |
Description |
|
Existing |
Indicates if the vegetation already existed on the site; deselect the option if the vegetation is expected to be added to the site |
|
Land Cover/vegetation type zones |
Select the type of zone for the vegetation; the associated standard index value displays in brackets. Enter text in the search box to filter the list. |
|
Biomass density index for this zone |
Displays the density index value for the selected zone |
In the Sustainability Dashboard, the total site area, and the Biomass Density Index (BDI) for the current site and the planned site display in the Overview view. Select participating layers, and select the correct biome for the vegetation.
As you add more biomass zones to the design, click Recalculate; the dashboard indicates the results. See The Sustainability Dashboard. As you modify the site and refresh the data, you'll see the changes to the biomass density index credit status. The credit status points will go up or down, depending on the BDI values, calculated as a percentage of the total area for participating objects.
The Details view lists each of the vegetation zones in the drawing, along with the calculations based on surface area and percentage of the total site for the zone, to come up with the BDI for each zone. The existing BDI displays for comparison.
Once you have achieved a design with required results, click Export to create a report that can be submitted or shared with an expert for review.
