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2026 Vol.68, Issue 4 Preview Page
Analysis of Temperature-Salinity-Based Stratification Characteristics of Estuarine Reservoir Using HSPF-EFDC Coupled Model and PEA Index

HSPF-EFDC 연계모형과 PEA 지표를 활용한 하구 담수호의 수온⋅염도 기반 성층화 특성 분석

Jaeyoung Ana
,
Sinae Kimb
,
Jihye Kwakb
,
Seongjae Parka
,
Suhwan Parka
,
Seoju Oha
,
Seonjae Parka
,
Jihye Kimc
,
Moon-Seong Kangd†
안 재영a
,
김 시내b
,
곽 지혜b
,
박 성재a
,
박 수환a
,
오 서주a
,
박 선재a
,
김 지혜c
,
강 문성d†
aM.S. Student, Department of Rural Systems Engineering, Seoul National University
bPh.D. Student, Department of Rural Systems Engineering, Seoul National University
cResearcher, Research Institute of Agriculture and Life Sciences, Seoul National University
dProfessor, Department of Rural Systems Engineering, Research Institute of Agriculture and Life Sciences, Institute of Green Bio Science and Technology, Seoul National University
† Corresponding author Tel.: +82-2-880-4582, Fax: +82-2-873-2087 E-mail: mskang@snu.ac.kr
2026. pp. 89-107
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Abstract

This study aimed to estimate watershed inflows to an estuarine reservoir using the Hydrological Simulation Program-Fortran (HSPF), simulate water level, temperature, and salinity dynamics using the Environmental Fluid Dynamics Code (EFDC), and quantify the spatiotemporal characteristics of stratification using the Potential Energy Anomaly (PEA) index. Previous studies on estuarine reservoirs have mainly focused on salinity or temperature distributions, while integrated quantification of stratification based on an energy perspective remains limited. To address this gap, a coupled watershed–reservoir modeling framework was developed and applied to the Ganwol estuarine reservoir. PEA was computed from EFDC outputs and summarized as volume-weighted means to reflect spatial variability. The results showed a seasonal pattern, with weak stratification in winter, rapid development in spring, peak conditions in summer, and decay in autumn. The mean PEA over the simulation period was 9.347 J/m³, indicating generally weak stratification, whereas strong stratification occurred mainly between May and September, with the highest frequency in June to August. Interannual variability in stratification intensity was also observed, suggesting the influence of thermal and salinity structures. Correlation analysis showed that PEA was strongly associated with surface–bottom temperature and salinity differences, while inflow and operational variables had relatively weak relationships. These findings indicate that stratification is primarily controlled by density differences associated with temperature and salinity rather than direct hydraulic effects. Periods and regions of strong stratification are likely to experience suppressed vertical mixing and increased risk of bottom water quality deterioration, suggesting the need for management strategies such as artificial mixing.

Keywords
Estuarine reservoir
stratification
PEA
salinity
HSPF
EFDC
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Information
  • Publisher :The Korean Society of Agricultural Engineers
  • Publisher(Ko) :한국농공학회
  • Journal Title :Journal of Korean Society of Agricultural Engineers
  • Journal Title(Ko) :한국농공학회논문집
  • Volume : 68
  • No :4
  • Pages :89-107
  • Received Date : 2026-01-26
  • Revised Date : 2026-04-23
  • Accepted Date : 2026-05-11
  • DOI :https://doi.org/10.5389/KSAE.2026.68.4.089
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