Potential risky exotic fish species, their ecological impacts and potential reasons for invasion in Korean aquatic ecosystems

ATIQUE USMAN,안광국 한국생태학회 2022 Journal of Ecology and Environment Vol.46 No.1

Background: Due to the rapidly changing climatic conditions, South Korea faces the grand challenge of exotic species. With the increasing human movement, the influx of alien species to novel regions is prevalent across the globe. The latest research suggests that it is easy to prevent the introduction and establishment of alien species rather than controlling their spread and eradication. Like other countries, the Korean Ministry of Environment released a list (in 2018) of 45 potential risky exotic fish species considered likely to be invasive candidate fish species if they ever succeed in entering the Korean aquatic ecosystems. Results: The investigation into the invasion suitability traits showed that potential risky fish species could utilize those features in becoming invasive once they arrive in the Korean aquatic ecosystems. If the novel species establish viable populations, they are likely to incur higher economic costs, damage the native aquatic fauna and flora, and jeopardize the already perilled species. Furthermore, they can damage the installed infrastructure, decline overall abundance and biodiversity, and disturb the ecosystem services. Here we reviewed the list of fish species concerning their family, native origin, preferred aquatic biomes, main food items, current status in Korea, and potential threats to humans and the ecosystems. Data shows that most species are either already designated as invasive in the neighboring counties, including Japan, Vietnam, Thailand, and China, or originate from these countries. Such species have a higher climate match with the Korean territories. Conclusions: Therefore, it is exceptionally essential to study their most critical features and take regulatory measures to restrict their entry. The incoming fish species must be screened before letting them in the country in the future. The regulatory authorities must highlight the threatening traits of such species and strictly monitor their entrance. Detailed research is required to explore the other species, especially targeting the neighboring countries fish biodiversity, having demonstrated invasive features and matching the Korean climate.

항만 환경에서 식물플랑크톤 잠재적 위해종의 분포

권오윤(Kwon, Oh Youn),강정훈(Kang, Jung-Hoon) 한국산학기술학회 2013 한국산학기술학회논문지 Vol.14 No.1

본 연구의 목적은 국내 주요항에서 출현하는 식물플랑크톤 잠재적 위해종의 시 공간적 변화를 파악하고, 환경요인 과의 관계를 이해하는데 있다. 부산, 울산, 인천 및 광양항에서 2007년 1월부터 12월까지 잠재적 위해종 및 환경요인을 계절별로 총 4회 조사하였다. 조사기간 중 출현한 잠재적 위해종은 총 25종으로, 이 중 적조 원인종이 20종이었으며 독소 생산종이 5종이었다. 적조 원인종인 Skeletonema costatum은 전 조사 지역에서 우점종으로 나타났다. 이 종은 부산항에서 수소이온농도와 양의 상관관계를, 용존산소와 음의 상관관계를 보였고(p<0.05), 울산항에서는 부유물질과 수소이온농도와 양의 상관관계를, 염분과 음의 상관관계를 보였다(p<0.05). 또한, 광양항에서는 염분 및 질산염과 양의 상관관계를, 수소이 온농도와 음의 상관관계를 보였고(p<0.05), 인천항에서는 질산염과 양의 상관관계를 보였다(p<0.01). 독소 생산종 중 기억 상실성 패독인 도모익 산을 배출하는 것으로 알려진 Pseudo-nitzschia spp.는 전 조사지역에서 출현하였고, 질산염 및 규산 염과 양의 상관관계를 보였다(p<0.05). 그리고 설사성 마비패독을 일으키는 Dinophysis acuminata 및 기억성 마비패독을 유발하는 Alexandrium spp.는 화학적 산소 요구량과 양의 상관관계를 보였다(p<0.01). 적조 원인종은 항구의 물리적 환경 요인에 영향을 받은 반면 독소 생산종은 영양염류와 같은 화학적 요인에 영향을 받는 것으로 나타났다. This study aimed to understand relationship between potential risky species and environmental factors at ports in Korea. During the study periods, 25 potential risky species (red tide and toxic species) representing 20 red-tide species, 5 toxic species were observed in the all ports. Skeletonema costatum (red-tide species) was predominated in all study area. This species showed positive correlation with pH, while negative correlation with dissolved oxygen (p<0.05) at Busan port. Also, this species showed positive correlation with total suspended solids and pH (p<0.05) at Ulsan port. However, Sk. costatum showed positive correlation with nitrate at Incheon port (p<0.01). Pseudo-nitzschia spp. producing amnesic shellfish poison (domoic acid) showed positive correlation with nitrate and silicate in all study areas (p<0.05). Alexandrium spp. (paralytic shellfish poison) and Dinophysis acuminata (diarrhetic shellfish poison) were affected by chemical oxygen demand (p<0.01). Our results indicated that red-tide species were affected by physical factors, while chemical factors affected toxic species.

잠재적 위해종인 야광충의 항만 분포 특성과 수용능력

강정훈 한국해양과학기술원 2010 Ocean and Polar Research Vol.32 No.4

Ongoing port baseline surveys are essential for developing ballast water management procedures in order to control unwanted or potentially risky species. Seasonal distributional patterns of marine dinoflagellate Noctiluca scintillans internationally recognized as harmful species and the related environmental factors were surveyed at Incheon, Gwangyang and Ulsan seaports in Korea from 2007 to 2009. The above three seaports were chosen because of their status as the busiest in Korea and characterized by their different bioregions. Average temperature ranged from 2.08℃ in winter to 26.39℃ in summer at Incheon, 7.22℃ in winter to 25.77℃ in summer at Gwangyang, and 11.59℃ in winter to 21.67℃ in summer at Ulsan during the study period. Average salinity varied from 26.88 in winter to 31.25 in summer at Incheon, 22.83 in winter to 33.41 in summer at Gwangyang, and 30.04 in winter to 33.90 in summer at Ulsan. Noctiluca scintillans appeared consistently at all ports during the study period, indicating its eurythermal and euryhaline nature. The highest abundances (21,813 to 41,753 inds·m−3) of N. scintillans were observed in May 2008 and 2009 at the outer stations of Incheon port. Abundances of between 10,000 and 30,000 inds·m−3 were only observed at the innermost station of Ulsan in May, while abundances of between 10,000 and 40,000 inds·m−3 were frequently observed throughout all stations at Gwangyang during the study period, coinciding with consistently high concentration of chlorophyll-a (hereafter chl-a) (4.32-8.24 μg l−1) compared to other ports. Spatio-temporal variation of chl-a concentration was not significantly correlated with abundances of N. scintillans (p>0.01). However, relatively high chl-a concentrations were consistently recorded along with high abundances of N. scintillans throughout all stations at Gwangyang compared to other ports. Abundances of N. scintillans observed at the three surveyed ports did not significantly (p>0.01) affect the concentration of dissolved oxygen in the surface mixed layer, indicating that the species abundances were not enough to cause reduction of dissolved oxygen during the study period. Presented results indicated that the Gwangyang seaport may provide the most suitable environment for a wide range of N. scintillans blooming compared to other ports.

인천항 내, 외에서 식물플랑크톤 위해종의 분포특성

권오윤(Kwon, Oh Youn),강정훈(Kang, Jung-Hoon) 한국산학기술학회 2014 한국산학기술학회논문지 Vol.15 No.11

인천항에서 선박평형수 배출수에 기인한 외래종을 고려한 항만환경 관리수준 설정을 위해 식물플랑크톤의 잠재적 위해종 출현 특성과 관련된 환경영향 요인을 2007년 2월부터 2009년 11월까지 인천항 내측 및 외측에서 계절조사를 수행하였 다. 조사결과, 한국 주변해역에서 출현한 바 있는 식물플랑크톤 62종이 관찰되었고, 그 중에 적조원인종 13종과 독소생산종 7종의 잠재적 위해종이 관찰되었다. 잠재적 위해종은 여름철과 겨울철에 인천항 외측에서 더 다양하게 출현하였다. 봄과 겨 울철에는 적조원인종인 Skeletonema spp., Thalassiosira nordenskioldii, Paralia sulcata가 항만 내측 (평균 72.4%) 및 외측 (평균 77.6%)에서 모두 우점 하였고, 수소이온과 부유물질의 농도와 양의 상관관계를 나타냈다(p<0.05). 여름철에는 인천항 내측에서 적조원인종(Skeletonema spp.) 및 독소생산종(Alexandrium catanella, A. tamarense, Dinophysis acuminata, Pseudo-nitzschia spp.)이 혼합 우점 (평균 74.2%) 하였으나, 외측에서는 Skeletonema spp.와 P. sulcata가 우점 (평균 67.2%) 하였다. 연구기간 동안 출현한 독소생산종 들은 용존 무기질산염, 규산염, 인산염 및 화학적 산소요구량과 양의 상관관계를 나타냈다(p<0.05). 식물플랑크톤 엽록소-a 농도는 봄과 여름 및 가을철에 인천항 외측에서 각각 평균 3.05 ㎍/L, 1.49 ㎍/L, 5.46 ㎍/L로 내측보다 3-5배 높은 농도가 높았고, 겨울철에는 내측 (평균 0.94 ㎍/L) 및 외측 (평균 0.95 ㎍/L) 간 농도 차이가 없었다. 요약하면, 인천항 외측은 다양한 적조원인종이 우점하며 엽록소-a 농도가 높았으나, 항만 내측은 여름철 독소생산종 의 출현 종수가 높게 나타났고, 외측에 비해 엽록소-a 농도가 낮았다. 각 위해종들의 대 발생 가능성은 영양염, 화학적 산소요 구량 및 부유물질의 농도와 비례한 것으로 나타나, 항만 내, 외측의 환경특성을 고려한 잠재적 위해종 관리가 요구된다. This study examined the occurring pattern of potential risky species and the related abiotic factors for port-specific environmental management considering the control of ballast water-induced foreign species at Incheon seaport. From a total of 62 species observed during the study, 13 red-tide and 7 toxic phytoplankton, normally occurring species in Korean waters, occurred from the seasonal investigation at the inner and outer sites of the Incheon seaport from 2007 to 2009. The number of potential risky phytoplankton was relatively high at the outer site of the port during summer and winter. Red-tide species, such as Skeletonema spp., Thalassiosira nordenskioldii, and Paralia sulcata, dominated the total standing crops at the inner site (avg. 72.4%) and outer site (avg. 77.6%) in spring and summer, being positively correlated with the concentrations of total suspended solids (TSS) and pH (p<0.05). In summer, the red-tide species (Skeletonema spp.) and toxic species (Alexandrium catenella, A. tamarense, Dinophysis acuminata and Pseudo-nitzschia spp.) co-dominated (avg. 74.2%) at the inner site, while Skeletonema spp. and P. sulcata predominated (avg. 67.2%) at the outer site. During the study periods, the toxic species were significantly and positively correlated with the chemical oxygen demand (COD), dissolved inorganic nitrogen, silicate and phosphate (p < 0.05). The chlorophyll-a (chl-a) concentration of phytoplankton at the outer site ranged from 1.49 to 5.46 ㎍/L on average, which was 3-5 times higher than that at the inner site in spring, summer and autumn, whereas there was no difference in the concentration between inner (avg. 0.94 ㎍/L) and outer (avg. 0.95 ㎍/L) sites in winter. In summary, diverse red-tide species dominated and a relatively high chl-a concentration existed at the outer site, whereas a relatively high number of toxic species and low chl-a concentration was observed at the inner site in summer. The potential risky species can outbreak in association with the concentration of nutrients, COD and TSS, suggesting that distinctive management of potential risky species is needed considering the environmental characteristics of Incheon seaport.