Rooted Macrophytes Options

If the user wished to use the Rooted Plant and Epiphyte Model (RPEM), the Use checkbox under Rooted Macrophytes frame should be checked as shown in Figure 1. The Modify button in the Rooted Macrophytes frame allows the user to set various constants associated with RPEM, as shown in Figure 2.

Figure 1. Rooted Macrophytes Options.

The General tab  in the RPEM form allows the user to enable or disable a variety of combinations for RPEM, including enabling the simulation of rooted plants or epiphytes; enabling epiphytes growing on rooted plants; enabling RPEM – Water Column Nutrient Interaction; and enabling RPEM – Sediment Diagenesis Interaction.  For details on the theory behind this sub-model, please refer to "A Generic Rooted Aquatic Plant and Epiphyte Algae Sub-Model for EFDC" (Hamrick, 2006).

Figure 2. RPEM: General.

The Initial Conditions tab is shown Figure 3. This tab allows the user to set various approaches for the RPEM, such as: Constant IC's, Spatially varying IC's - WQRPEMSIC.INP, and Spatially varying IC's - WQRPEMRST.INP. These later options allow the user to input variable carbon biomasses rather than set them as constant values. Clicking on any of the buttons for setting shoot, root, epiphyte, or detritus carbon ICs will display a form as shown in Figure 4. Using this form the user may import a poly file or a data file for the IC.

Figure 3. RPEM: Initial Conditions.

Figure 4. RPEM: Initial Conditions: Shoot Carbon

The Rates tab allows the user to set growth and respiration rates among other parameters for shoots, roots, and detritus, as shown in Figure 5.

Figure 5. RPEM: Rates.

The Nutrient Limits tab allows the user to set parameters for growth and respiration rates limitation, as shown in Figure 6.

Figure 6. RPEM: Nutrient Limits.

Root and shoot temperatures may be set in the R & S Temperature tab as shown in Figure 7.

Figure 7. RPEM: Root & Shoot Temperature.

Constants for epiphyte growth respiration, light limitation, and temperature effects for growth and respiration may be set in the Epiphytes tab as shown in Figure 8.

Figure 8. RPEM: Epiphytes.


The Nutrient Fractions tab allows the user to set nutrient fractions. It has five sub-tabs Shoot, Root, Epiphyte, Shoot Detritus, and G-class, as shown in Figure 9.


Figure 9. RPEM: Nutrient Fractions.

The sub-tabs Shoot, Root, and Epiphyte has the same form, as shown in Figure 10.


Figure 10. Nutrient Fractions: Shoot, Root, Epiphyte.

Forms settings for the sub-tabs Shoot Detritus and G-class, as shown in Figure 11 and Figure 12.


Figure 11. Nutrient Fractions: Shoot Detritus.


Figure 12. Nutrient Fractions: G-class.

Values of the RPEM settings are saved in the file "wq_rpem.jnp" of the model folder.