The Shellfish Farm module has been developed to simulate flow fields around the mariculture rafts and the impact of cultivation practices on the growth and development of any species of shellfish.
This module can only be activated by checking on the Use box of the Shellfish Farm Options from the Biota tab of the Water Quality form as shown in Figure 1.
Figure 1. Activate Shellfish Farm Module.
When the user clicks the OK button (Figure 1), the Shellfish Farm sub-module will be added to the Modules on the Model Control. RMC on Shellfish Farm module sub-tab under the Modules tab, then click the Settings option to open Shellfish Farm form as shown in Figure 2 below (the Shellfish Farm form can also be accessed by clicking on the Modify button in Figure 1) . In this form, first set the Number of Shellfish Species. The form has five other tabs below: Model Settings, Shellfish Species, Farm Settings, Harvest and Initial Conditions. Each tab has a range parameters that may be configured as described in the following sections.
Figure 2. Shellfish Farm Settings.
Model Settings
In Model Settings it is necessary to check the Interact with Water Quality Module box to link the input data of water quality parameters (as shown in Figure 3) to the water quality module in EFDC.
The interaction of the shellfish farm with water quality parameters depends on the number of water quality parameters simulated in the water quality module settings as shown in Figure 4. A value of 1 or 0 means that parameter simulated or not simulated respectively.
Figure 3. Shellfish Farm Model Settings.
Figure 4. Water Quality Parameters Simulation Settings.
Editing Species
In the Shellfish Farm form the user should identify the Number of Shellfish Species they want to add to the model and then define the characteristics of each species. Click on the Edit Species button to open the Shellfish Species form to set species characteristics.
Figure 5. Edit Shellfish Species.
In this form the user can set the name of the species to be simulated. The shellfish parameters should be based on the aquatic ecological characteristics of this species. These parameters can be defined by eight tabs (From Figure 6 to Figure 13): General, Infiltration, Respiration, Growth, Mortality, Excretion, Spawning, Larvae. Refer to the EFDC+ Theory Guide to learn how these parameters impact the shellfish life cycle. The larvae characteristics are for information only at this stage and not user configurable.
When defining characteristics of the shellfish completed, the characteristics are also displayed on the Shellfish Species tab as shown in the Figure 14.
Figure 6. Shellfish species characteristics : General.
Figure 7. Shellfish species characteristics: Infiltration.
Figure 8. Shellfish species characteristics: Respiration.
Figure 9. Shellfish species characteristics: Growth.
Figure 10. Shellfish species characteristics: Mortality.
Figure 11. Shellfish species characteristics: Excretion.
Figure 12. Shellfish species characteristics: Spawning.
Figure 13. Shellfish species characteristics: Larvae.
Figure 14. Shellfish Species Tab.
Farm Settings
In the Farm Settings tab (Figure 15), the user should first assign the total number of model cells they want to configure to have shellfish in the Number of Shellfish Cells form using the Assign button. The Number of Farming Zones should also be set. The corresponding number of farming groups will be created in the Shellfish Farming Zones form. A farming zone will have particular characteristics. Currently the farm type and the depth at which the farm is to be set are not used. However, the species death rate should be set for the number of individuals that die in that zone per day.
Figure 15. Farm Settings Tab.
Shellfish Initial Conditions
In the Initial Conditions tab assign the position and the initial number of individuals of the species as shown in Figure 16 below. From this tab, under Initial Individuals and Harvest Rate frame,
- L, J, J columns: cell index of the shellfish farm
- Zone: Farm zone index
- IC# Species Name: Initial number of individuals
Figure 16. Shellfish Farm Initial Conditions.
Harvest Times
If shellfish harvesting to be simulated at certain time then this can be set in the Harvest tab. The Number of Harvests to be conducted during the simulation period should be entered. In the Harvest Settings form sets the mid-point of the harvest time of the shellfish as well as the minimum weight of shellfish that can be harvests in grams of carbon. The day of harvest is the model Julian time. For example, if the model run time starts at day 1 then day 200 is the midpoint of the shellfish is harvest, with the calculation effectively instantaneous. The harvest will occur on that day, but will only apply to individuals larger than the minimum size, smaller individuals will not be harvested.
Figure 17. Harvest Times Tab.
Harvest Rates
Click the Edit button in the Harvest column, and the form for Harvest Rate Setting will be displayed. In this form the user can set the day and harvest rate for this species in this cell as a proportion of the total number of individuals, with 0 meaning harvest, and 1 all individuals are harvested.
Figure 18. Harvest Rates Tab.
Figure 19. Harvest Rates Setting.
After completing these settings, click the OK button to save the settings, close the form and finish configuring the shellfish module.