해상가두리 어류양식의 생산 특성과 기후 반응 분석

다국어 초록 (Multilingual Abstract)

Aquaculture has established itself as an important source of seafood supply, and marine cage aquaculture in Korea occupies a significant position within the marine finfish production. As of 2025, fish produced through aquaculture account for only about 3.2 percent of total mariculture output by volume, yet represent approximately 35.7 percent of total mariculture production value. Because this production system depends directly on open coastal waters, it is highly exposed to changes in seawater temperature, salinity, and related environmental conditions. Climate change therefore poses not only short-term risks to growth and survival, but also longer-term risks to productivity, regional production structure, and management stability. This dissertation analyzes the production structure of Korean marine cage aquaculture and the climate response of Korean rockfish （Sebastes schlegelii） aquaculture production—the most representative species in marine cage operations—with particular attention to nonlinearity in the production regime, stocking effects on production vulnerability and regional heterogeneity in climate sensitivity. This dissertation consists of three empirical essays. The first essay applies a fixed-effects panel threshold model to examine whether finfish production density in marine cages exhibits a nonlinear production structure in which the effect of stocking density on output density varies with current biomass density levels. The second essay applies a panel smooth transition regression model to analyze whether the climate response of Korean rockfish production density changes with current biomass density levels, and to evaluate the extent to which biomass density adjustment may mitigate production density and revenue losses under high-temperature conditions. The third essay employs a Poisson pseudo-maximum likelihood model to estimate the effects of climate and marine environmental variables on Korean rockfish production density across major producing regions and to project future regional production density changes under SSP climate scenarios. The first essay applies a fixed-effects panel threshold model to semiannual panel data from four major producing districts—Namhae, Taean, Yeosu, and Tongyeong—for 2011–2025. A statistically significant single threshold is identified in current stocking density at a log value of 5.9569, equivalent to approximately 386.41 fish per square meter. Below this threshold, stocking input density exhibits a positive elasticity of 0.1313 with respect to production density, indicating that expanding operational scale is associated with proportional production gains. Above the threshold, this elasticity declines to 0.1030, revealing diminishing marginal returns to additional stocking inputs under high stocking density conditions. Moist pellet density has a significant positive association with production density, while formulated pellet density and water temperature both show significant negative associations. The second essay applies a panel smooth transition regression （PSTR） model to semiannual panel data from four provinces— Jeonnam, Gyeongnam, Chungnam, and Gyeongbuk—for 2011–2025, with current stocking quantity as the transition variable. The estimated transition point is 16.35 in logarithmic stocking quantity, equivalent to approximately 12.61 million fish, and the transition speed is 1.40, indicating that the shift in temperature response occurs gradually rather than abruptly. Critical temperatures differ markedly across production regimes. In the small-scale regime, the critical temperature falls below the lower bound of the observed temperature range, so temperature increases within the observed range tend to be associated with production gains. In the medium-scale regime, the critical temperature is estimated at 22.54°C, and in the large-scale regime it falls to 19.57°C, meaning that even moderate temperature increases can push large-scale operations into a production-declining range. Scenario analysis confirms that large-scale production regimes face the greatest production and revenue losses under high-temperature conditions, and that downward adjustment of stocking quantity is estimated to yield substantial mitigation of these losses. The third essay shows that Korean rockfish production responds to climate and marine environmental variables in a nonlinear and regionally heterogeneous manner. Water temperature is the most consistent and influential factor across regions. Jeollanam-do and Chungcheongnam-do show relatively strong vulnerability to warming, while the effects in Gyeongsangnam-do and Gyeongsangbuk-do become more unfavorable as temperatures rise. Salinity functions as a region-specific moderating variable rather than a uniform national risk factor; in Jeollanam-do it tends to amplify production decline, whereas in other regions the direction and magnitude of its effect vary by scenario, suggesting that salinity change may either cushion or compound the impact of rising temperatures depending on local conditions. Scenario projections for 2030–2050 indicate that, relative to the 2016–2025 average, the production shares of Jeollanam-do and Chungcheongnam-do decrease across all three SSP scenarios, while those of Gyeongsangnam-do and Gyeongsangbuk-do increase. Under the temperature pathway of SSP2-4.5, for example, the share of Jeollanam-do decreases by 2.7 percentage points while that of Gyeongsangnam-do increases by 4.3 percentage points. Both the HHI and Theil index increase under all scenarios, suggesting that future Korean rockfish production is likely to become more regionally concentrated. The policy implications of this dissertation are as follows. First, production management in Korean marine cage aquaculture should move beyond volume-driven expansion and instead adopt biomass-responsive density management that keeps current stocking density below the ecological threshold. Second, high-temperature response systems should be differentiated by both current temperature conditions and stocking quantity levels at each production site, rather than applying uniform thermal thresholds. Third, climate adaptation strategies should be designed on a region-specific basis, accounting for the heterogeneity in climate sensitivity documented across regions. Overall, this dissertation demonstrates that the sustainability of Korean marine cage aquaculture under climate change depends not only on environmental exposure itself, but on the interaction between production regime structure, stocking conditions, and regional characteristics.

목차 (Table of Contents)

• Ⅰ. 서론 1
• 제1절 연구의 배경 및 목적 1
• 1. 연구 배경 1
• 2. 연구 목적 5
• 제2절 연구의 방법 및 구성 6
• 1. 연구 범위 6
• 2. 연구 방법 7
• 3. 연구 구성 9
• 제3절 선행연구 검토 11
• 1. 어류양식 생산의 비선형 구조와 패널문턱모형 11
• 2. 사육량에 따른 기후 민감도 전환과 PSTR 모형 14
• 3. 기후변화와 양식생산의 효과 및 시나리오 전망 17
• 4. 선행연구와의 차별성 21
• Ⅱ. 해상가두리 양식업과 기후환경 현황 분석 23
• 제1절 해상가두리 양식업의 구조와 생산 현황 23
• 1. 해상가두리 양식업의 개념과 특성 23
• 2. 해상가두리 양식업의 생산 현황 24
• 3. 조피볼락 양식의 생산 현황 42
• 제2절 해상가두리 양식업의 기후환경 현황과 미래 변화 전망 48
• 1. 주요 기후·해양환경 변수 현황 48
• 2. SSP 시나리오 적용 미래 전망 55
• Ⅲ. 해상가두리 어류양식 생산의 사육밀도 문턱효과 분석 59
• 제1절 이론적 배경 59
• 1. 생산함수 이론 59
• 2. 패널회귀모형 61
• 3. 패널문턱모형 62
• 제2절 실증 분석 65
• 1. 분석 자료 65
• 2. 선형 패널회귀모형의 추정 결과 69
• 3. 비선형 패널모형의 추정 70
• 제3절 소결 78
• Ⅳ. 조피볼락 양식생산의 사육량별 수온 반응과 피해 분석 81
• 제1절 이론적 배경 81
• 1. 패널 단위근 검정 81
• 2. 평활전환회귀모형 82
• 3. 패널평활전환회귀모형 84
• 4. 생산변화 및 사육규모 수준 간 피해 격차 추정 86
• 제2절 분석 결과 91
• 1. 분석 자료 91
• 2. 단위근 검정과 선형성 검토 93
• 3. PSTR 추정결과 96
• 4. 사육규모 수준별 기후 취약성 비교 101
• 제3절 소결 108
• Ⅴ. 조피볼락 양식생산의 기후 반응과 미래 생산구조 분석 111
• 제1절 이론적 배경 111
• 1. 포아송 의사최우추정 111
• 2. 시나리오 기반 생산량 예측 112
• 3. 생산집중도 및 공간불균등도 지표 114
• 제2절 실증 분석 116
• 1. 분석 자료 116
• 2. PPML 모형 분석결과 118
• 3. 한계효과 121
• 4. SSP 시나리오를 이용한 예측 생산량 변화 125
• 5. 생산구조의 변화 129
• 제3절 소결 136
• Ⅵ. 결론 139
• 제1절 연구 및 분석 결과 요약 139
• 1. 연구 요약 139
• 2. 정책적 시사점 144
• 제2절 연구의 의의 및 한계점 147
• 1. 연구의 의의 147
• 2. 연구의 한계 및 향후 연구 과제 148
• 참고문헌 151