초록 ▼

1. “해양생태계 교란생물”이라 함은 외국으로부터 인위적 또는 자연적으로 유입되어 해양생태계의 교란을 가져오거나 가져올 우려가 있는 해양 생물을 뜻한다.
2. 수온 상승과 선박 평형수로 인하여 외래종의 유엽이 증가하고 유해 생물들 밀도가 증가하여 생태계 교란이 빈번하게 열어나고 있다. 이 교란 생물은 인간에게도 직접, 간접적으로 큰 영향을 주고 있다.
3. 본 과제의 목표는 막대한 피해를 주는 해양 교란생물인 유독성 플랑크톤과 유해성 비브리오균의 생리/생태학적 연구를 통하여 대량 발생 빚 번식 기작을 규명하고, 이들 생물

1. “해양생태계 교란생물”이라 함은 외국으로부터 인위적 또는 자연적으로 유입되어 해양생태계의 교란을 가져오거나 가져올 우려가 있는 해양 생물을 뜻한다.
2. 수온 상승과 선박 평형수로 인하여 외래종의 유엽이 증가하고 유해 생물들 밀도가 증가하여 생태계 교란이 빈번하게 열어나고 있다. 이 교란 생물은 인간에게도 직접, 간접적으로 큰 영향을 주고 있다.
3. 본 과제의 목표는 막대한 피해를 주는 해양 교란생물인 유독성 플랑크톤과 유해성 비브리오균의 생리/생태학적 연구를 통하여 대량 발생 빚 번식 기작을 규명하고, 이들 생물에 대한 효과적인 제어 기술을 개발하여 해양생태계 복원 빚 건강한 해양생태계를 유지 및 관리하도록 하는 것이다.
4. 본 연구에서는 그동안 외국에서만 보고되었던 종 및 선종 유독/유해 플랑크톤성 교란생물 (11종)의 국내 해역 출현을 국제학술지를 통하여 처음 보고하였다. 그 중 5종은 형태 및 분자생물학적 분석을 통하여 아열대종임을 밝혔다. 또한 독침을 가진 것으로 밝혀진 Paragymnodinium shiwhaense는 산속, 산종으로 보고하였다.
이들 11종과 기존에 알려진 2종을 후보 종으로 선정하였다.
5. 유해성 비브리오의 경우 종 별 DNA 마커를 개발한 후 전국 연안 분포 조사를 한 결과, 4개의 해역에서만 매우 낮은 농도로 발견되었다.
6. 물리 화학적 방법(차아염소산나트륨, 황산철, 황토)을 통한 교란생물 제어 방법을 개발하였으며 ,대체종을 이용하여 교란된 해양생태계를 친환경적으로 복원할 수 있는 적정 투입 농도 또한 제시하였다.
7. 유독/유해 플랑크톤성 교란생물을 제어할 수 있는 원생동물성 천적생물 5종을 개발하였다. 특히 그동안 효과적인 천적이 없는 것으로 알려진 맹독성 플랑크톤들에 대한 천적을 찾아냈는데, 이 종이 신종으로 밝혀져 Gyrodinium moestrupii라고 명명하여 국제학술지를 통하여 신종으로 발표하였다.
8. 유독/유해 플랑크톤성 교란생물 대체 생물종을 선정하고 투입 농도를 산출하여 대체 생물 종 투입을 통한 교란된 해양생태계 복원방안을 제시하였다.
9. 본 연구 결과는 유독/유해 플랑크톤성 교란생물을 신속히 탐색하고 제어, 관리하는데 큰 기여를 할 수 있을 것으로 판단된다.

Abstract ▼

4. Results
The results obtained during this project are followings; (1) We obtained basic data on the presence of Toxic/Harmful Plcmktonic Disturbance Organisms and Vibrio spp. from 15 times sampling from ca. 31 locations along the Korean coastal line from January, 2009 to September, 2012. From t

4. Results
The results obtained during this project are followings; (1) We obtained basic data on the presence of Toxic/Harmful Plcmktonic Disturbance Organisms and Vibrio spp. from 15 times sampling from ca. 31 locations along the Korean coastal line from January, 2009 to September, 2012. From these samples, we isolated ca. 20 Toxic/Harmful Planktonic Disturbance species and succeeded cultivation of these species.
(2) By using these cultures, we tested several contents such as their toxicity, disturbance to other organisms and their predation. Based on these results, we selected 13 species (Alexandrium hiranoi, Amphidinium carterae, Azadinium poporum, Biecheleria cincta, Coolia malayensis, Gymnodinium aureolum, Heterosigma akashiwo, Karlodinium venefium, Ostreopsis cf. ovata, Pfiesteria piscicida,Paragymnodinium shiwhaense, Prorocentrum cf. rhathymum, Symbiodinium sp.) as candidate species of Toxic/Harmful Planktonic Disturbance Organisms. (3) Further, we developed specie specific DNA markers of these 13 candidate species, and (4) by using these markers, we investigated distribution and introduction of these species in national-wide Korean coastal area(total 31 locations) during experimental period. Alexandrium hiranoi, one of the Toxic/Harmful Planktonic Disturbance candidate species, was first isolated from Shiwha bay, Korea. During project periods, we investigated distributions of this species using species specific DNA marker. Based on this result, we found that this organism also distributed in the Busan coastal area in low concentration. Another candidate species, Azadinium poporum was first isolated from sediments collected in Shiwah bay, and discovered that this species are widely distributed around nation-wide Korean coastal area in low concentration. Other candidate species Coolia malayensis, Ostreopsis cf. ovata, and Prorocentrm cf. rhathymum were known toxic. These species were found mostly around Jeju coastal area and also found in very limited area of southern coastal waters.
(5) In this project, we alsoinvestigated trophic modes(autotrophic, heterotrophic, and mixotrophic), growth rate, feeing rate, arazing rate, toxicity, physiology, and biochemistry of these candidate Toxic/Harmful Planktonic Disturbance Organisms. For example, the maximum mixtrophic growth of G.aureolum on cryptomonad Teleaulax sp. was 0.169 d^-1, while the maximum phototrophic growth rate of G.aureolum under light condition of 20uE m^-2s^-1 was 0.120 d^-1, and its maximum ingestion rate was 3.4 cells grazer^-1d^-1. In addition, when temperature tolerance of Ostreopsis cf. ovata was tested, it did not grow at the temperature <10℃ and> 40℃, however, it could grow at a growth rate of 0.33 d^-1 at 20℃. Further, life cycle of Paragymnodinium shiwhaense, isolated from Shiwha bay Korea was established as a new genus and new species by our team and revealed that this species can conduct both asexual and sexual cycle and can feeds on prey using a peduncle.
(6) We investigated effective physical-chemical method of sontrolling Toxic/Harmful Planktonic Disturbance Organisms such as NaOCI, red clay, iron sulfate. NaOCI obtained by electrolysis of sea water was tested whether it killed Alexandrium hiranoi, Azadinium poprum, Coolia malayensis, Gymnodinium aureolum, Karlodinium venefium, Ostreopsis cf. ovata, Pfiesteria piscicida, Paragymnodinium shiwhaense, Prorocentrum cf. rhathymum, and Symbiodinium sp.. All candidate species were killed at 0.3-1 ppm NaOCI; all cells of Heterosigma akashiwo were killedat 0.3 ppm, Alexandrium hiranoi, Amphidinium carterae, Biecheleria cincta, Pfiesteria piscicida, Paragymnodinium shiwhaense at 0.5 ppm, Azadinium poporum, Coolia malayensis, Karlodinium veneficum, Symbiodinium sp. at 0.75 ppm, Ostreopsis cf. ovata and Prorocentrum cf. rhathymum at 1 ppm.
(7) In this project, our team succeeded in developingnatural predators on these candidate species, and also measured growth and grazing rates of predator species feeding on the candidate species. One of the predator species, Gyrodinium moestrupii, isolated and reported as new species in the international journal by our team, was revealed to feed on highly toxic planktonic disturbing organisms. Further, other predator species, Gyrodinium dominans was revealed to feed well on Alexandrium minutum, Alexandrium tamarense, while other predator species Polykrikos kofoidii and Favella sp. was able to feed toxic disturbance organism, A. hiranoi. In addition, we newly discovered Oxyrrhis marina, G. dominans, G. spirale, Pfiesteria piscicida, Strobilidium sp. as predator species of Azadinium poporum, while G.moestrupii and P. Kofoidi as new predator species of disturbance organism, Coolia canariensis and C. malayensis. Furthermore, we newly discovered that O. marina, G. dominans, P. piscicida, P. kofoidii, Protoperidinium bipes, Strobilidium sp., and Strombidinopsis sp. were effective predators on Eutreptiella gymnastica.
(8) We tested the effectiveness of natural predators on these candidate species as well as their influences to marine ecosystem by using mesocosms in actual field conditions. This experiment was conducted at Kunsan outer port during July, 2012 and in Shiwha bay area during September, 2012. In the Field experiment, mass cultured Oxyrrhis marina cells were added as a predator for Amphidinium carterae, Heterocapsa rotundata, and Heterosigma akashiwo, while Gyrodinium moestrupii was added for Ostreopsis cf.ovata into experimental mesocosms. Simultaneously, control mesocosms(predators only and prey only) were established. As a result, O. marian fed well on H. akashiwo in the mesocosms as results in laboratory experiments. While the concentration of H. akashiwo increased from 20,400 cells ml^-1 to 56,500 cells ml^-1 after 66 h in the control mesocosms, the concentration in the experimental mesocosms decreased from 19,300cells ml^-1 to ca. 100 cells ml^-1. Further, O. marina also reduced by 90% the concentration of A. carterae in the experimental mesocosms after 54 h, but the concentration of A. carterae in the control mesocosms remained almost unchanged. Furthermore, in 48 h incubation, G. moestrupii reduced the concentration of O. ovata in the experimental mesocosms from 980 cells ml^-1 to 600 cells ml^-1, but the concentration of O.ovata in the control mesocosms increased from 885 cells ml^-1 to 1,120 cells ml^-1.
(9) We developed rapid detection systems of Toxic/Harmful Planktonic Disturbance Organisms introduction. We chose Shiwha bay and Masan Bay for establishing this system. In Shiwha bay, several toxic/harmful planktonic disturbance organisms have been found and some new species have been isolated. Inaddition, Masan bay is hghly enriched due to inflow of sewage from land and blooms of some Toxic/Harmful Planktonic Disturbance Organisms have been frequently observed. Further, diverse ships with diverse nationalities passes and anchors in Masan bay, therefore, introduction of alien speciescan occur. Five stations on the costal-line and 10 stations inside the bay were selected as sampling stations. Several environmental factors such as water temperature, salinity, pH, nutrients, and dissolved exygen are planned to be measured. For monitoring Toxic/Harmful Planktonic Disturbance Organisms, real-time PCR analysis using species specific DNA markers were conducted.
(10) To restore marine ecosystem disturbed by Toxic/Harmful Planktonic Disturbance Organisms, we suggest eco-friendly methods(i.e., replacing other harmless species with these harmful organisms). Tol replace smaller sized Toxic/Harmful Planktonic Disturbance Organisms(i.e., Azadinium poporum, Karlodinium veneficum, Symbiodinium sp., Paragymnodinum shiwhaense, Pfiesteria piscicida), harmless species such as Heterocapsa rotundata, Rhodomonas salina, Skeletonema costatum, Prorocentrum minimum, Heterocapsa triquetra can be provided. Furthermore, for larger sized Toxic/Harmful Planktonic Disturbance Organisms(i.e., Coolia malayensis, Ostreopsis cf. ovata, Prorocentrum cf. rhathymum, Alexandrium hiranoi), harmless species such as Scrippsiella trochoidea, Prorocentrum micans, Akashiwo anguinea can be offered as replacement species.
(11) Further, to manage Toxic/Harmful Planktonic Disturbance Organisms effectively, we produced a manual. This manual contained figures and characteristics of 13 candidate Toxic/Harmful Planktonic Disturbance species, monitoring methods, their controlling methods, and alert system when these species are introduced to Korean coastal waters.