Characterizing habitat connectivity in a small river using ecohydraulic modeling and network-based indices

Young-Jun Kim; Joo-Heon Lee; Sang-Hyeok Park; Kyung A You; Seo-Yeon Park

doi:10.3741/JKWRA.2026.59.S-1.793

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2026 Vol.59, Issue 7S-1 Preview Page Next Page

Characterizing habitat connectivity in a small river using ecohydraulic modeling and network-based indices 생태수리 모형과 네트워크 지수를 활용한 중소하천 서식지 연결성 특성 분석

31 July 2026. pp. 793-803

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Abstract

This study was conducted to quantitatively evaluate habitat connectivity disrupted by transverse hydraulic structures in a river and to assess their impacts on ecological continuity by integrating Ecohydraulic modeling with index-based analysis. The study area is the Jicheon Stream, a tributary of the Geum River in South Korea, where a total of 40 weirs have been constructed. Daily discharge data from 2000 to 2024 were utilized to estimate the optimal flow for Cobitis choii, which was subsequently applied as the reference flow for Ecohydraulic modeling. Hydraulic and hydrologic simulations were performed using HEC-RAS, HEC-GeoRAS, and HEC-GeoEFM to estimate habitat areas under pre- and post-weir installation conditions. The degree of habitat fragmentation was quantified using the River Fragmentation Index (RFI) and the Change of River Fragmentation Index (CRFI). In addition, four indices Dendritic Connectivity Index (DCI), Population Connectivity Index (PCI), Catchment Area-based Fragmentation Index (CAFI), and Integral Index of Connectivity (IIC) were applied to comprehensively evaluate the structural and functional connectivity of the river. By comparing the results of the index-based evaluation with those of Ecohydraulic modeling, this study verified the consistency and complementarity between the two approaches. The integrated evaluation framework proposed herein enables a multidimensional diagnosis of habitat fragmentation according to the presence or removal of river structures, and it is expected to provide a scientific basis for prioritizing river restoration projects and establishing management strategies for aquatic ecosystem health.

Keywords

Habitat connectivity

Ecological flow

River restoration

Ecohydrology

본 연구는 하천 내 횡단구조물에 의해 단절된 서식지 연결성을 정량적으로 평가하고, 생태수리 모델링과 지수 기반 분석을 통합하여 생태계 연속성에 미치는 영향을 규명하기 위해 수행되었다. 연구 대상하천은 금강의 지류하천인 지천으로 총 40개의 보가 설치되어 있다. 유량 분석에는 2000 ~ 2024년 일유량 자료를 활용하여, 미호종개의 최적 유량을 산정하고 생태수리 모델링을 위한 기준유량으로 반영하였다. 수리·수문 모델링은 HEC-RAS, HEC-GeoRAS, HEC-GeoEFM을 이용하여 보 설치 전·후 조건별 서식지 면적(Habitat Area)을 산정하였고, 서식지 단절 정도를 정량화하기 위해 RFI (River Fragmentation Index) 및 CRFI (Change of River Fragmentation Index)를 산정하였다. 또한, 하천의 구조적·기능적 연결성을 통합적으로 평가하기 위해 DCI (Dendritic Connectivity Index), PCI (Population Connectivity Index), CAFI (Catchment Area-based Fragmentation Index), IIC (Integral Index of Connectivity) 등 네 가지 지수를 적용하였다. 본 연구는 지수 기반 평가와 생태수리 모델링 결과를 상호 비교함으로써, 두 접근법의 정합성과 보완 가능성을 검증하였다. 이를 통해 하천 구조물의 존재 및 철거에 따른 서식지 단절성을 다차원적으로 진단할 수 있는 통합적 평가 프레임워크를 제시하였으며, 향후 하천 복원사업의 우선순위 설정과 수생태계 건강성 관리 전략 수립에 기초자료로 활용될 수 있을 것으로 기대된다.

키워드

서식지 연결성

생태유량

서식처 복원

생태수문학

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Information

Publisher :KOREA WATER RESOURECES ASSOCIATION
Publisher(Ko) :한국수자원학회
Journal Title :Journal of Korea Water Resources Association
Journal Title(Ko) :한국수자원학회 논문집
Volume : 59
No :7
Pages :793-803
Received Date : 2025-12-03
Revised Date : 2026-01-19
Accepted Date : 2026-01-29
DOI :https://doi.org/10.3741/JKWRA.2026.59.S-1.793

Journal of Korea Water Resources Association ISSN:2799-8746(Print) 2799-8754(Online) 한국수자원학회 논문집

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