Assessing Salinity Reduction by Environmental Restoration in the Seomjin River Estuary (South Korea): A Numerical Model Approach for Corbicula Habitat Conservation
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area
2.2. EFDC Model Description
2.3. Data Setup for a Simulation Model
2.3.1. Environmental Changes at Daap Water Intake and Sand Mining Works
2.3.2. Measured Hydrological Data for Simulations of the EFDC Model
2.4. Model Application for Salinity Simulation
2.5. Ranges of Salinity for Habitable Environments of Corbicula
3. Results
3.1. Model Calibration and Validation
3.2. Derivation of the Optimal Discharge for Habitable Corbicula Environments
3.3. Analysis of Salinity Reduction Effects under Various Scenarios
3.3.1. Riverbed Restoration
3.3.2. Submerged Weir
3.3.3. Groynes
3.3.4. Comprehensive Evaluation of Structural Scenarios
4. Discussion
- (1)
- The analysis of average salinity reduction effects enables the assessment of whether the structural scenarios applied as models fulfill the overall salinity concentration conditions suitable for corbicula growth by delaying or preventing natural seawater flow.
- (2)
- By analyzing the vertical distribution of salinity concentrations to investigate saltwater stratification during neap tides, it is possible to identify sections of the riverbed where corbicula growth is feasible despite an overall reduction in average salinity concentrations. This distinction is based on the salinity distribution in the riverbed where corbicula grows.
- (3)
- By analyzing the penetration distance of salinity concentrations into the riverbed, it is possible to evaluate the sections suitable for optimal corbicula habitat conditions, considering both the average salinity concentration and the high salinity stagnation phenomenon at the riverbed.
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Daap Intake (m3/s) | Discharge at Gurye-gun (Songjeong-ri) (m3/s) | Model Simulated Result (psu) | |||||
---|---|---|---|---|---|---|---|
Seomjin Bridge | Seomjin River Bridge | Hwamok | |||||
Spring Tide | Neap Tide | Spring Tide | Neap Tide | Spring Tide | Neap Tide | ||
2.523 | 5 | 16.45 | 19.94 | 21.79 | 25.70 | 26.38 | 27.94 |
10 | 12.64 | 19.12 | 18.76 | 25.52 | 24.50 | 27.60 | |
15 | 7.98 | 18.01 | 15.68 | 24.96 | 22.20 | 27.16 | |
20 | 3.60 | 16.75 | 12.88 | 24.54 | 20.34 | 25.98 | |
25 | 2.17 | 15.52 | 11.62 | 23.99 | 19.22 | 26.29 | |
30 | 1.46 | 14.33 | 10.41 | 23.49 | 18.25 | 25.98 | |
35 | 0.98 | 13.16 | 9.98 | 23.01 | 17.94 | 25.74 | |
3.125 | 5 | 16.83 | 20.07 | 22.03 | 25.75 | 26.44 | 27.94 |
10 | 13.13 | 19.29 | 19.15 | 25.54 | 24.69 | 27.61 | |
15 | 8.44 | 18.10 | 16.04 | 25.12 | 22.32 | 27.22 | |
20 | 3.77 | 16.91 | 12.89 | 24.69 | 20.38 | 26.02 | |
25 | 2.25 | 15.65 | 11.82 | 24.05 | 19.29 | 26.29 | |
30 | 1.48 | 14.44 | 10.51 | 23.61 | 18.29 | 26.02 | |
35 | 1.01 | 13.32 | 10.23 | 23.10 | 18.02 | 25.80 | |
3.912 | 5 | 17.32 | 20.09 | 22.47 | 25.81 | 26.68 | 27.96 |
10 | 13.45 | 19.37 | 19.48 | 25.58 | 24.74 | 27.66 | |
15 | 9.22 | 18.34 | 16.48 | 25.21 | 22.61 | 27.28 | |
20 | 4.22 | 17.15 | 13.37 | 24.77 | 20.60 | 26.32 | |
25 | 2.39 | 15.84 | 11.90 | 24.17 | 19.29 | 26.37 | |
30 | 1.60 | 14.82 | 10.89 | 23.95 | 18.65 | 26.32 | |
35 | 1.07 | 13.53 | 10.29 | 23.30 | 18.05 | 25.89 | |
4.630 | 5 | 17.83 | 20.19 | 22.85 | 25.89 | 26.84 | 28.04 |
10 | 14.13 | 19.58 | 19.89 | 25.67 | 24.90 | 27.68 | |
15 | 9.57 | 18.54 | 16.89 | 25.32 | 22.74 | 27.34 | |
20 | 4.34 | 17.36 | 13.52 | 24.88 | 20.71 | 26.11 | |
25 | 2.43 | 16.03 | 12.03 | 24.30 | 19.29 | 26.43 | |
30 | 1.60 | 14.82 | 10.65 | 23.78 | 18.45 | 26.11 | |
35 | 1.12 | 13.72 | 10.47 | 23.35 | 18.18 | 25.92 |
Scenarios | Description | Model Application | Application Map |
---|---|---|---|
Riverbed Restoration | A method of raising the downstream water level by uniformly elevating the existing riverbed throughout the 1 to 17 km stretch from the Seomjin River estuary, achieved through activities such as sand mining. | For EFDC grid (i, j) Grids 63–69 and 70–215: Increasing the existing downstream water level values by ① 1 m, ② 2 m, and ③ 3 m | |
Submerged Weir | The installation of three underwater dams between the 1 to 6 km stretch from the Seomjin River estuary, designed to maintain a constant water level or slow the water flow. | For EFDC grid (i, j) ① Grids 63–69 and 71: An increase of 2 m, 3 m, and 4 m from the existing downstream water level values. ② Grids 63–69 and 87: An increase of 2 m, 3 m, and 4 m from the existing downstream water level values. ③ Grids 63–69 and 98: An increase of 2 m, 3 m, and 4 m from the existing downstream water level values. | |
Groynes | To prevent the flow, four weirs are installed within the river channel, positioned between the 4 and 6 km stretch from the Seomjin River estuary. | For EFDC grid (i, j): ① Grids 63–66 and 90: Implementing a method to raise the existing downstream water level values by 1 m, 2 m, and 3 m. ② Grids 66–69 and 92: Implementing a method to raise the existing downstream water level values by 1 m, 2 m, and 3 m. ③ Grids 63–66 and 94: Implementing a method to raise the existing downstream water level values by 1 m, 2 m, and 3 m. ④ Grids 66–69 and 96: Implementing a method to raise the existing downstream water level values by 1 m, 2 m, and 3 m. |
Scenarios | Discharge at Gurye-gun (Songjeong-ri) (m3/s) | Water Intake at Daap (m3/s) | Riverbed Restoration (m) | Average Salinity (psu), Salinity Reduction (psu, RRS-0 Minus Each Scenarios) | |||
---|---|---|---|---|---|---|---|
Dugok (Spring/Neap Tides) | Sinbi (Spring/Neap Tides) | Mokdo (Spring/Neap Tides) | Hwamok (Spring/Neap Tides) | ||||
RRS-0 | 10 | 3.912 | 0 | 6.6/9.1, - | 15.2/22.9, - | 19.2/24.4, - | 28.6/29.4, - |
RRS-1 | 1 | 3.8/2.8, −2.8/−6.3 | 10.6/17.2, −4.6/−5.7 | 15.3/19.3, −3.9/−5.1 | 27.2/29.0, −1.4/−0.4 | ||
RRS-2 | 2 | 2.6/1.0, −4.0/−8.1 | 8.3/11.0, −6.9/−11.9 | 13.1/14.2, −6.1/−10.2 | 26.0/28.5, −2.6/−0.9 | ||
RRS-3 | 3 | 2.2/0.2, −4.4/−8.9 | 8.6/9.9, −6.6/−13.0 | 14.7/12.9, −4.5/−11.5 | 25.8/28.8, −2.8/−0.6 |
Scenarios | Discharge at Gurye-gun (Songjeong-ri) (m3/s) | Water Intake at Daap (m3/s) | Submerged Weir Height (m) | Salinity (psu), Salinity Reduction (psu, RRS-0 Minus Each Scenarios) | |||
---|---|---|---|---|---|---|---|
Dugok (Spring/Neap Tides) | Sinbi (Spring/Neap Tides) | Mokdo (Spring/Neap Tides) | Hwamok (Spring/Neap Tides) | ||||
SWS-0 | 10 | 3.912 | 0 | 6.6/9.1, - | 15.2/22.9, - | 19.2/24.4, - | 28.6/29.4, - |
SWS-1 | 2 | 6.6/9.1, −0.0/−0.0 | 15.2/22.8, −0.0/−0.1 | 19.2/24.4, −0.0/−0.0 | 28.6/29.4, −0.0/−0.0 | ||
SWS-2 | 3 | 6.6/9.1, −0.0/−0.0 | 15.2/22.8, −0.0/−0.1 | 19.1/24.4, −0.1/−0.0 | 28.5/29.3, −0.1/−0.1 | ||
SWS-3 | 4 | 6.6/9.0, −0.0/−0.1 | 15.1/22.7, −0.1/−0.2 | 19.1/24.2, −0.1/−0.2 | 28.5/29.3, −0.1/−0.1 |
Scenarios | Discharge at Gurye-gun (Songjeong-ri) (m3/s) | Water Intake at Daap (m3/s) | Groynes Height (m) | Salinity (psu), Salinity Reduction (psu, RRS-0 Minus Each Scenarios) | |||
---|---|---|---|---|---|---|---|
Dugok (Spring/Neap Tides) | Sinbi (Spring/Neap Tides) | Mokdo (Spring/Neap Tides) | Hwamok (Spring/Neap Tides) | ||||
GS-0 | 10 | 3.912 | 0 | 6.6/9.1, - | 15.2/22.9, - | 19.2/24.4, - | 28.6/29.4, - |
GS-1 | 1 | 6.5/8.9, −0.1/−0.2 | 15.0/22.6, −0.2/−0.3 | 19.0/24.2, −0.2/−0.2 | 28.4/29.4, −0.2/−0.0 | ||
GS-2 | 2 | 6.4/8.7, −0.2/−0.4 | 14.8/22.2, −0.4/−0.7 | 18.7/23.8, −0.5/−0.6 | 28.1/29.4, −0.5/−0.1 | ||
GS-3 | 3 | 6.2/8.3, −0.4/−0.8 | 15.1/22.7, −0.1/−0.2 | 18.4/23.1, −0.8/−1.3 | 27.7/29.3, −0.9/−0.1 |
Scenarios | Discharge at Gurye-gun (Songjeong-ri) (m3/s) | Water Intake at Daap (m3/s) | Height (m) | Salinity (psu), Salinity Reduction (psu, RRS-0 Minus Each Scenarios) | |||
---|---|---|---|---|---|---|---|
Dugok (Spring/Neap tides) | Sinbi (Spring/Neap Tides) | Mokdo (Spring/Neap Tides) | Hwamok (Spring/Neap Tides) | ||||
No | 10 | 3.912 | 0 | 6.6/9.1, - | 15.2/22.9, - | 19.2/24.4, - | 28.6/29.4, - |
All | Riverbed restoration 3 m+ Submerged Weir 4 m + Groyne 3 m | 2.0/0.1, −4.6/−9.0 | 8.5/9.5, −6.7/−13.4 | 14.1/11.1, −5.1/−13.3 | 25.5/28.5, −3.4/−0.9 |
Scenarios | Height (m) | Salinity (15 psu) Intrusion Distance (km) | Salinity (20 psu) Intrusion Distance (km) | Salinity (25 psu) Intrusion Distance (km) |
---|---|---|---|---|
No | - | 17.9 | 15.9 | 13.1 |
Riverbed restoration | 3 m | 14.5 (−3.4) | 12.0 (−3.9) | 9.6 (−3.5) |
Submerged Weir | 4 m | 17.9 (−0.0) | 15.9 (−0.0) | 13.0 (−0.1) |
Groyne | 3 m | 17.7 (−0.2) | 15.8 (−0.1) | 12.7 (−0.4) |
All | Riverbed restoration 3 m + Submerged Weir 4 m + Groyne 3 m | 14.2 (−3.7) | 11.9 (−4.0) | 9.5 (−3.6) |
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Lee, G.; Park, J.; Jung, C.; An, Y. Assessing Salinity Reduction by Environmental Restoration in the Seomjin River Estuary (South Korea): A Numerical Model Approach for Corbicula Habitat Conservation. Sustainability 2024, 16, 5653. https://doi.org/10.3390/su16135653
Lee G, Park J, Jung C, An Y. Assessing Salinity Reduction by Environmental Restoration in the Seomjin River Estuary (South Korea): A Numerical Model Approach for Corbicula Habitat Conservation. Sustainability. 2024; 16(13):5653. https://doi.org/10.3390/su16135653
Chicago/Turabian StyleLee, Gayeong, Jongyoon Park, Chunggil Jung, and Yunkeun An. 2024. "Assessing Salinity Reduction by Environmental Restoration in the Seomjin River Estuary (South Korea): A Numerical Model Approach for Corbicula Habitat Conservation" Sustainability 16, no. 13: 5653. https://doi.org/10.3390/su16135653