Spatio-Temporal Analysis of Bed Morphology and Grain-size Distribution Changes around a Woody Vegetation Patch in a Large-scale River Experiment

Eunkyung Jang; Un Ji

doi:10.17820/eri.2025.12.4.231

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2025 Vol.12, Issue 4 Preview Page Next Page

Original Article

Spatio-Temporal Analysis of Bed Morphology and Grain-size Distribution Changes around a Woody Vegetation Patch in a Large-scale River Experiment 실규모 하천 실험을 통한 목본성 식생패치 주변의 시공간적 하상변동 및 하상토 입도 분포 변화 분석

31 December 2025. pp. 231-239

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Abstract

This study quantitatively analyzed bed morphological changes around an artificial vegetation patch in a large-scale outdoor flume from spatial, temporal, and material perspectives. Comparison of drone imagery and 3D laser scanning data revealed contrasting spatial patterns: pronounced scour at the patch front (near the upstream boundary) and concentrated deposition in the wake region (approximately 3-5 times the patch length downstream). Time-series observations using acoustic-based monitoring showed rapid initial scour followed by progressive stabilization, with sediment accumulation in the wake zone over time. Grain-size analysis further indicated heterogeneous material responses. At lateral locations of the vegetation patch, fines were reduced and coarsening was observed, whereas the patch interior and wake region showed increased fines and fining. Both the uniformity coefficient and curvature coefficient decreased overall, suggesting a general tendency toward homogenization of sediment distribution. These findings demonstrate that vegetation patches act not merely as flow-disturbing obstacles but as key drivers that structurally reorganize bed morphology and sediment sorting characteristics. The study provides experimental evidence of vegetation-bed interactions under full-scale conditions and offers baseline data for vegetated channel management and river restoration strategies.

Keywords

Bed morphodynamics

Grain-size distribution

Large-scale flume experiment

Vegetation patch

Woody vegetation bar

본 연구에서는 대규모 야외 수로에서 인공 식생패치를 설치하고, 실험 전후 하상변동을 공간·시간·재료적 관점에서 정량적으로 분석하였다. 드론 영상과 3차원 레이저 스캐너 자료의 비교 분석 결과, 식생패치 전면부(상류 측 경계부근)에서는 뚜렷한 세굴이, 식생패치 후류영역(하류 측 약 식생패치 길이의 3~5배 범위)에서는 퇴적이 집중적으로 발생하는 상반된 공간적 하상형태가 확인되었다. 음향 기반 모니터링을 통한 시계열 관측에서는 실험 초기의 급격한 세굴과 시간이 지남에 따라 후류영역에서 퇴적이 누적되며 변화 양상이 점차 안정화되는 과정이 관찰되었다. 또한 지점별 입도 분석 결과, 식생패치 측면 지점에서는 세립분이 감소하여 조립화가 진행된 반면, 내부와 후류영역에서는 세립분이 증가하는 세립화가 나타났다. 균등계수와 곡률계수는 전반적으로 감소하여 입도 분포가 균질화 되는 경향이 확인되었다. 이러한 결과는 식생패치가 단순한 흐름 교란 요소를 넘어, 국지적인 하상 형성과 재료 분급 특성을 구조적으로 재편성하는 핵심 인자임을 보여준다. 본 연구는 실규모 조건에서 식생–하상 상호작용을 정량적으로 규명하였다는 점에서 학술적 의의가 있으며, 식생하천 관리 및 하천복원 전략 수립에 필요한 기초 자료를 제공한다.

키워드

하상변동

하상토 입도 분포

실규모 하천 실험

식생패치

목본성 식생사주

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Information

Publisher :Korean Society of Ecology and Infrastructure Engineering
Publisher(Ko) :응용생태공학회
Journal Title :Ecology and Resilient Infrastructure
Journal Title(Ko) :응용생태공학회 논문집
Volume : 12
No :4
Pages :231-239
Received Date : 2025-10-10
Revised Date : 2025-11-16
Accepted Date : 2025-11-24
DOI :https://doi.org/10.17820/eri.2025.12.4.231

Ecology and Resilient Infrastructure ISSN:2288-8527(Online) 응용생태공학회 논문집

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