가막만 북서내만해역에서 매년 여름 발생하는 빈산소수괴는 해양환경에 악영향을 미쳐왔다. 따라서, 본 연구는 빈산소수괴 발 생시기의 집중적인 현장조사 결과를 바탕으로 다중회귀분석(MRA)을 이용하여 빈산소수괴의 종합적인 발생 메커니즘을 밝혀내고, 그 주 요인에 따른 빈산소수괴 관리방안의 방향성을 모색하였다. 그 결과, 2017년 첫 빈산소수괴는 6월 26일에 발생하였으며, 기상 조건에 의한 수온약층의 형성과 퇴적된 유기물의 영향으로 형성되었다. 이어 7월 12일에는 강우량의 증가에 의한 염분약층의 형성으로, 조사 시기 중 빈산소수괴가 수직 및 수평적으로 가장 크게 확장되었다. 그리고, 8월 8일에는 소량의 강우로 빈산소수괴가 크게 약화되었으며, 이때 주 요인은 Chlorophyll-a 농도 증가(식물플랑크톤 증식)과 퇴적된 유기물이었다. 그리고, 약 1주일 후인 8월 16일에는 많은 강우량에 기인한 매우 안정된 염분약층과 Chlorophyll-a 농도 증가(식물플랑크톤 증식)에 의해 크게 확장된 빈산소수괴가 재발생하였다. 이후 9월 13일의 빈산 소수괴 소멸시기에서는 빈산소수괴가 해저 면을 따라 얕게 확장되었으며, 퇴적된 유기물에 의해 주로 영향을 받은 것으로 나타났다. 이는 빈산소수괴 관리를 위해서는 퇴적된 유기물의 개선뿐만 아니라 성층의 완화 기술이 필요함을 암시하였다.

Global warming affects critical natural resources, one of which is the oceans that occupy 70% of the total cover of the earth. In other words, ocean warming is a subset of global warming which needs to be addressed urgently. Purple laver (pyropia spp.) is one of the most vulnerable items to climate change although it is a major export product of Korean fisheries. The purpose of this study is to analyze the causality of how climate change caused by global warming affects the increase or decrease of PLP (purple laver production). The target area for analysis was set to Maro-hae between Jindo-gun and Haenam-gun. We selected marine environmental factors and meteorologic factors that could affect PLP as variables, as well as co-integration tests to determine long-term balance, and the Granger causticity tests. As a result, PLP and marine environmental factors WT (water temperature), pH, and DO confirmed that long-term equilibrium relationships were established, respectively. However, there is only causality with WT and it is confirmed that there is only a correlation between pH and DO (dissolved oxygen). There was no long-term equilibrium relationship between PLP and HDD (heating degree days) and there is a causal effect that HDD affects PLP; however, it was less clear than that of WT. The relationship between PLP and RF (rainfall), WS (wind speed), SS (percentage of sunshine), and FF (farm facilities) was all balanced in the long term, and causality exists. Based on the results of the analysis, policy proposals were made.

The relationship between the environmental factors (water temperature, salinity, chlorophyll-a concentration, Noctiluca scintillans density, Diatoms and Dinoflagellates densities) and the zooplankton community was investigated. Zooplankton were seasonally collected at 11 stations of Gwangyang Bay from November 2015 to July 2016. A mean abundance ranged from 544 to 19,753 indiv. m-3. The maximum abundance was observed to be 40,000 indiv. m-3 in July and the minimum occurred in November with 412 indiv. m-3. The zooplankton consisted of 35 taxa, which is dominated by Paracalanus parvus s. l., Corycaeus spp., Oithona spp., Acartia omorii, A. ohtsukai, Centropages abdominalis, unidentified harpacticoids. The result of the Redundancy Analysis (RDA) conducted between the zooplankton and the environmental factors showed that the spring-autumn, summer and winter are separated. The summer was closely related to temperature and diatom density, while the winter was linked to salinity and N. scintillans density (p<0.05).