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The application of this work is to use a single generalized wetland shape parameter in conjunction with V-h Model [Eq. (2.1)] to represent the stage-storage behavior of multiple wetlands and lakes. Table 2.3 lists the generalized shape parameters that were calculated using the three statistical averages (mean, median and mV) for the four

individual wetland categories, the lake category, and for the three wetland groups: Case I – cypress wetlands, marsh wetlands and lakes located in west-central Florida, Case II –

wetlands and lakes identified in Table 2.1. Additionally, the V-h Model performance results produced using the general shape parameters and the wetland category specific shape parameters (specific m) are presented in Table 2.3. The results are listed as summary statistics of the RMSERel and VARE for each wetland category or group. The stage-storage model [Eq. (2.1)] will be referred to as a general V-h Model when general shape parameters are incorporated and as a specific V-h Model when wetland or lake specific shape parameters are incorporated.

Table 2.3. Generalized shape parameter evaluation.

Case Data Set General m RMSERel* (%) VARE(%) VOP

m Statistic Ave StD Min Max Ave StD Min Max (%)

Specific m 2.2 1.6 0.6 4.6 4.9 4.0 1.1 10.2 60 3.0 mean 15.8 14.2 0.6 36.8 52.9 54.9 1.3 139.5 40 2.7 median 14.3 10.4 4.6 29.8 45.8 41.7 10.3 113.4 60 Cypress 3.0 mV 15.8 14.2 0.6 36.8 52.9 54.9 1.3 139.5 40 Specific m 2.5 1.9 1.5 5.8 3.6 2.2 1.6 7.1 20 2.5 mean 2.5 median 12.8 7.2 2.0 19.9 31.6 20.9 3.7 57.4 40 Marsh 2.5 mV Specific m 2.4 1.7 0.8 6.5 5.7 5.7 1.3 22.8 53 2.5 mean 16.6 13.9 2.3 62.3 42.0 38.1 4.7 173.7 47 2.3 median 18.0 16.4 3.1 74.0 47.0 47.1 6.7 211.0 47 Lake 2.2 mV 19.1 18.2 1.3 80.8 50.4 53.3 1.2 232.6 65 Specific m 1.0 0.5 0.4 1.8 2.7 1.7 0.4 5.2 20 2.1 mean 5.2 2.9 2.3 9.8 12.1 7.8 5.3 24.9 40 2.0 median 5.2 3.6 1.2 9.5 11.8 9.0 2.3 22.4 60 St. Denis Pothole 2.1 mV 5.2 2.9 2.3 9.8 12.1 7.8 5.3 24.9 40 Specific m 0.8 0.3 0.4 1.3 1.6 1.0 0.4 3.6 60 1.5 mean 5.9 3.9 1.7 14.1 15.4 10.5 3.9 35.7 40 1.4 median 6.1 6.4 1.1 20.0 16.4 18.3 2.1 50.9 60 N. Dakota Pothole 1.5 mV 5.9 3.9 1.7 14.1 15.4 10.5 3.9 35.7 40 Specific m 2.4 1.6 0.6 6.5 5.2 4.9 1.1 22.8 48 2.6 mean 15.4 11.7 1.2 57.2 40.2 34.7 1.8 157.5 44 2.5 median 15.8 12.6 0.6 62.3 42.1 38.3 1.3 173.7 48 I C,M,L+ 2.2 mV 19.2 16.6 1.3 80.8 53.6 53.5 1.2 232.6 67 Specific m 1.5 1.3 0.4 5.8 2.9 2.4 0.4 10.2 44 2.1 mean 17.0 12.6 2.3 55.6 46.6 44.6 5.3 208.2 36 2.0 median 17.2 14.6 1.2 61.7 47.7 51.4 2.3 230.1 40 II C,M,St.D, _N.D+ 1.6 mV 25.3 25.0 2.1 94.9 72.2 84.9 4.1 347.2 68 Specific m 1.8 1.5 0.4 6.5 4.0 4.3 0.4 22.8 48 2.3 mean 17.5 12.9 1.4 74.0 46.4 39.5 3.4 211.0 36 2.2 median 17.8 14.3 1.3 80.8 47.8 44.8 1.25 232.6 45 III All 2.0 mV 19.5 18.1 1.2 96.7 53.8 57.9 2.3 283.3 50

+ _{C, M, St.D, N.D, L = Cypress, Marsh, St. Denis NWA and North Dakota wetlands, and Lakes.}

* RMSERel = RMSEV-h normalized by the maximum wetland volume (Vo).

The general V-h Model results were obtained by predicting the wetland stage-storage relationships for each wetland in a category or group using the general shape parameter developed from each of the three averages. Likewise, the specific V-h Model results (Table 2.3 – Specific m) were obtained using the specific wetland shape parameters listed in Table 2.1 (100% Vo). These parameters were used to predict the stage-storage

relationships of the individual wetlands and lakes in each category and group. Summary statistics were then calculated for the respective general V-h Model predictions and the specific V-h Model predictions for all wetlands in the particular category or group. The general V-h Model performance was evaluated by comparing the respective RMSERel and

VARE results (Table 2.3) to that of the specific V-h Model RMSERel and VARE results (Table 2.3 – Specific m). The optimal general shape parameter for each wetland category and group was determined by identifying the general V-h Model with the least deviation from the specific V-h Model RMSERel and VARE results.

2.6.1.1. Individual Wetland Categories

The general shape parameters developed from the three statistical measures (mean, median and mV) had little variation within the individual wetland categories. The largest range of shape parameter values for the individual wetland categories was 0.3 found in the cypress and lake wetland categories (Table 2.3). The cypress general shape

parameter ranged from 2.7 (median) to 3.0 (mean and mV), and the lake general shape parameter ranged from 2.2 (mV) to 2.5 (mean). The range of parameter values for the St.

parameter values calculated for the individual wetland categories ranged from 1.4 (North Dakota pothole) to 3.0 (cypress). In order to gain some perspective of the errors

associated with this shape parameter range, the RMSERel and VARE were calculated for all the wetlands in this study (Case III). The average RMSERel and VARE associated with each general shape parameter are: 42.2% and 120.4% (m = 1.4) and 19.9% and 48.4% (m = 3.0).

Another analysis was performed to determine the number of wetlands needed to develop an effective general shape parameter for use in the V-h Model. For this exercise, the lake and pothole wetland categories (St. Denis and North Dakota) were chosen because they had the most entries, 17 lakes and 15 pothole wetlands (Table 2.1). The number of entries used to calculate the general shape parameter was incrementally increased from two to the maximum number of entries in each data set. The order of the lakes and pothole wetlands were randomly chosen before the calculations were performed. This procedure was repeated several times for each data set. The mean shape parameter for the lakes became constant, m ≈ 2.5, when the data set was comprised of five to 10 lakes. Also, the mean shape parameter for the pothole wetlands became constant, m ≈ 1.7, when the data set was comprised of five to 10 wetlands. The specific number of entries

required to stabilize the shape parameter varied based on the order of selection. If the first entries had a shape parameter near the mean, fewer entries were needed; conversely if the first entries had a shape parameter far from the mean, more were needed to reach a stable value. This analysis suggests that a minimum of five to 10 wetlands might be

needed to develop a general shape parameter(s) that can be used to describe the stage- storage characteristics of multiple wetlands and lakes.

2.6.1.2. Wetland Groups

The generalized shape parameters for the Case I, Case II and Case III wetland groups are listed in Table 2.3. The Case I general shape parameters ranged from 2.2 (mV) to 2.6 (mean), the Case II shape parameters ranged from 1.6 (mV) to 2.1 (mean), and the Case III shape parameters ranged from 2.0 (mV) to 2.3 (mean). The largest general shape parameter range was 0.5 found in Case II, which was comprised of all wetlands except lakes. However, the Case III scenario, consisting of all 42 wetland and lakes, had a reduced range of general shape parameters (0.3).

2.6.2. General V-h Model Performance