This study analyzed the structural characteristics and influencing factors of fish assemblages according to lake size (small, medium, large) based on fish survey data from 90 lakes designated under the National Aquatic Ecosystem Health Monitoring Program in Korea. From surveys conducted between 2022 and 2024, a total of 107 fish species belonging to 32 families were recorded. The dominant species was the bluegill (Lepomis macrochirus, relative abundance [RA]: 21.2%), followed by Hemiculter eigenmanni as the subdominant species (RA: 13.6%). Statistical analysis based on lake size revealed significant differences across eight ecological indicators including species richness, abundance, diversity, evenness, richness, dominance, number of endemic species, and number of exotic species according to lake size. These indicators tended to increase with lake size. While this pattern may be initially attributed to positive factors associated with larger lakes, such as greater habitat heterogeneity and food resource diversity, it is considered that the primary factor influencing these results is the difference in the number of sampling sites per lake. Since sampling sites were designated based on the national water quality monitoring network, they are considered representative of each lake’s environmental conditions. Bray-Curtis similarity and SIMPER analyses identified patterns in assemblage similarity and the key contributing species for each size group. This study provides empirical evidence that demonstrates the influence of lake size on fish assemblage composition and structure and highlights the necessity of incorporating lake size and typology into fish-based assessments of lentic ecosystem health.

This study investigates how lake morphology, water quality, and water-level fluctuations (WLF) collectively shape wetland plant communities across 90 lakes in the Republic of Korea. By analyzing morphological indices (Index of Basin Permanence; IBP, Rawson Index; RI), WLF, water quality, and vegetation data, we identified four distinct lake groups through cluster analysis. Group C, comprising large dams, was characterized by the highest IBP and extreme WLF. Despite having favorable water quality, this group exhibited the lowest species richness, suggesting that severe physical disturbance from WLF is a primary limiting factor for wetland plant community. In contrast, Group A (estuarine reservoirs) showed stable water levels but high nutrient concentrations, which led to eutrophic conditions and communities dominated by a few tolerant species. Group D, which included small agricultural reservoirs and floodplain wetlands, had complex shorelines (highest RI) and supported the higher diversity of aquatic plants. This indicates that habitat heterogeneity can mitigate moderate physical disturbances and enhance richness. Canonical Correspondence Analysis and Variation Partitioning Analysis revealed that community structure is primarily influenced by hydrological disturbance, chemical stress (eutrophication), salinity, and shoreline complexity. These analyses confirmed that the interplay of these environmental factors explains community variation more effectively than any single factor alone. Our findings demonstrate that lake plant communities are shaped by a complex interaction of geomorphological, hydrological, and chemical factors. Therefore, effective lake management must adopt an integrated approach, considering both water-level regulation and shoreline complexity to enhance ecological integrity.

Sanghuang mushroom is highly valued for its medicinal potential, including anticancer, anti-inflammatory, and antioxidant activities, and has recently gained significant economic and pharmacological importance. Despite considerable taxonomic revisions within the genus Sanghuangporus, confusion persists in Korea due to the continued use of outdated names such as Phellinus linteus, P. baumii, and Inonotus baumii, as well as inconsistencies in common names. This study aimed to clarify the species diversity of Sanghuangporus in Korea through integrative approaches combining phylogenetic, morphological, and ecological analyses. Using four genetic markers (ITS, nLSU, RPB2, and TEF1), we analyzed 11 dried specimens preserved at the Seoul National University Fungus Collection and 74 fungal strains maintained by the Korean Agricultural Culture Collection. As a result, we identified eight Sanghuangporus species in Korea: S. baumii, S. mongolicus, S. quercicola, S. sanghuang, S. subbaumii, S. vaninii, S. weigelae, and a novel candidate species, Sanghuangporus sp. 1. Among these, S. mongolicus and S. quercicola were newly recorded species for Korea. By providing diagnostic traits and ITS barcode sequences, this study offers a reliable taxonomic framework for the accurate identification of Sanghuangporus species. It also supports future taxonomic studies, cultivar development, and applied research in pharmaceutical and functional bioactive materials.

최근 증가한 상어의 출현빈도 증가는 상어 혼획의 증가와 더불어 상어에 의한 생태계 변화의 정밀 해석의 필요성으로 이어지고 있다. 안정동위원소는 생태학적 현상을 해석하 고 이해하는 데 사용되며, 상어의 이동에 대한 원인과 생태계 내 상어의 위치 및 생태를 이해하는데 도움이 될 수 있다. 본 총론에서는 한국의 상어 연구에서 영양 단계와 먹이 구성을 추정하고 이동 및 서식지 이용 패턴을 추론하기 위한 안정동위원소 기법의 활용을 제안하고자 한다. 연구자들이 이 접근법의 강점과 한계를 이해하는 데 도움을 주기 위해, 탄소 및 질소 안정동위원소의 영양 단계 판별 특성, 그리고 영양 단계 및 먹이 구성 추정을 위한 방법론적 고려 사항에 대한 간략한 개요를 제공하고자 하며 연골어류 특유의 특성에 대한 동위원소 기법의 주의 사항 및 화합물 안정동위원소비를 이용한 최신 연구도 소개한다. 안정동위원소 기법은 위내용물, 유전자, 생지화학적 마커와 공동 활용을 통해 상어 생태학에 대한 기본적인 의문을 해결하는 데 강력한 도구로 활용될 수 있을 것이다.

Our study develops a finite element analysis (FEA) model to evaluate the seismic performance of a two-story reinforced concrete (RC) school building and validates it through experiments. We developed a methodology that reflects failure modes from past experiments and validated it by comparing results at both the member (columns) and system (beam-column joints) levels. We created an FEA model for seismic-vulnerable RC moment frames using this methodology. This model incorporates bond-slip effects using three methods: Merged Nodes, Constrained Beam in Solid Penalty (CBISP), and Constrained Beam in Solid Friction (CBISF), which model the interaction between reinforcement and concrete. The approach provides a reliable tool for evaluating seismic performance and improves the accuracy of reinforced concrete frame evaluations.

The Indian Ocean is the second-largest tuna fishing ground in the world, accounting for approximately 1.2 million tonnes (23%) of the estimated 5.2 million tonnes of global commercial tuna catch in 2023. This study examined the relationship between tuna catches, specifically skipjack, bigeye, and yellowfin tunas, and prey biomass (Nautical Area Scattering Coefficient, NASC) estimated from acoustic surveys conducted in the southwestern Indian Ocean from 20 April to 15 May 2019. Environmental variables were derived from the Copernicus Ocean Model, and tuna length data from the IOTC. The estimated total tuna catch in the study area was approximately 166,400 tonnes, with the northwestern region showing the highest catches and NASC values. Tuna catches increased with NASC; however, the relationship was non-linear. While skipjack showed no significant correlation with NASC, bigeye and yellowfin tunas exhibited weak but significant positive correlations. Environmental analysis revealed that the northern waters had high surface temperatures, low salinity, and low oxygen levels, with mid and deep layers characterized by low temperature, salinity, oxygen, and chlorophyll. These findings offer a foundation for understanding tuna distribution in relation to prey and environmental conditions, highlighting the need for future species- and fishery-specific studies to support sustainable tuna resource management.

본 연구는 식물공장에서 미나리(Oenanthe javanica DC.) 를 초장별(20cm, 30cm, 40cm, 50cm)로 재배할 경우 기능성 물질과 영양학적 가치가 유지되는지를 평가하기 위해 수행되 었다. 미나리는 항산화 효과, 항염증, 간 보호 등 다양한 생리 활성을 갖춘 기능성 채소로, 기존 재배 방식의 한계를 극복하 고 연중 안정적인 생산이 가능한 식물공장 재배 가능성을 확 인하는 것이 본 연구의 목적이다. 연구 결과, 초장 30cm에서 칼륨(K)과 칼슘(Ca) 함량이 가장 높았으며, 비타민 C 함량 또 한 1,165.38mg·kg-1으로 가장 높았다. 총 폴리페놀 함량은 초 장 20－40cm에서 유사한 수준을 유지하였으며, 초장 50cm 에서 감소하는 경향을 보였다. 기능성 물질인 Quercetin, Apigenin, Isorhamnetin 함량은 초장에 따른 변동 폭이 크지 않아, 단기 재배된 초장이 짧은 미나리도 충분한 기능성 물질 을 함유하고 있음을 확인하였다. 식이섬유 함량 또한 모든 초 장에서 일정 수준(300g·kg-1 이상)을 유지하여 건강 기능성 채소로 활용 가능성이 높았다. 본 연구 결과를 종합하면, 식물 공장에서 초장 30cm로 재배된 미나리는 높은 영양 가치와 기 능성을 유지할 수 있으며, 기존 노지재배 방식과 비교해 연중 균일한 생산이 가능하여 산업적 활용 가치가 클 것으로 판단 된다.

본 연구는 식물공장형 육묘시스템에서 광도 조절에 따른 수 박 접목묘의 생육 및 품질을 평가하기 위해 수행되었다. 수박 접수는 고온기 품종 ‘부라보꿀(BK)’, 저온기 품종 ‘산타꿀 (SK)’을 사용하였고, 대목으로 고온기 품종 ‘불로장생(BS)’, 저온기 품종 ‘동장군(DG)’을 사용하였다. 광도는 125 ± 25, 225 ± 25 및 325 ± 25μmol·m-2·s-1 3처리로 조정하여 실험을 진행하였다. 초장은 고온기 접목묘가 125 ± 25μmol·m-2·s-1, 저온기 접목묘가 225 ± 25μmol·m-2·s-1에서 가장 높았고, 줄 기 직경과 마디수는 고온기 접목묘, 저온기 접목묘 모두 225 ± 25μmol·m-2·s-1에서 가장 높았다. 근장과 엽면적은 고온기 접 목묘에서 325 ± 25μmol·m-2·s-1, 저온기 접목묘는 225 ± 25 μmol·m-2·s-1에서 가장 높았다. 또한 지상부 및 지하부 생체중 과 건물중은 225 ± 25μmol·m-2·s-1 처리에서 가장 높게 나타 났다. 충실도는 두 품종 모두 광도가 증가함에 따라 높아졌으 며, 특히 고온기 접목묘에서 그 효과가 두드러졌다. 엽면적비 (LAR)는 고온기 접목묘에서 광도 증가와 함께 유의하게 증가 하였으나, 저온기 접목묘에서 유의한 차이가 없었다. 종합적 으로 생육 특성은 225 ± 25μmol·m-2·s-1에서 높았으나, 묘소 질을 고려했을 때 325 ± 25μmol·m-2·s-1에서 더욱 강건한 묘 가 형성된 것으로 판단된다.

본 연구는 울산광역시 유통 과채류 가공식품의 잔류농 약 오염도를 모니터링하여 소비자의 안전성을 평가하기 위해 수행하였다. 울산광역시 소재 대형마트와 온라인 쇼 핑몰을 통해 유통되고 있는 과일 및 채소 가공식품 120건 (과일류 58건, 채소류 62건)에 대해 잔류농약(401종)을 분 석하였으며, 검출률은 32.5%(39건)이었고, 총 48종의 농약 검출을 확인하였다. 한편, 2022년부터 2024년까지 울산광역시 보건환경연구 원(농수산물검사소)에서 수행한 비가공 농산물의 잔류농약 검출률과 비교했을 때, 과일 및 채소 가공식품의 검출률 은 60-70% 수준이었다. 또한 검출된 농약의 검출량은 모 든 시료에서 원료 농산물에 대한 한국 기준의 20% 미만 수준이었고, 위해도(%ADI) 평가 결과 0.0003-0.7658%로 모두 안전한 수준인 것으로 확인되었다. 본 연구는 가공식품과 일반 유통 농산물의 잔류농약 검 출률 및 검출 수준을 비교함으로써, 가공식품에서도 잔류 농약 관리가 필요함을 실증적으로 제시하였다. 다만, 조사 한 가공식품 검체의 수량 및 종류가 제한적이고, 비가공 농산물에 대한 자료는 울산광역시에 유통되는 농산물에 국한된 자료라는 점에서 한계가 있다. 따라서, 향후 연구 에서는 가공식품 검체를 더 많이 확보하고, 비가공 농산 물에 대한 자료는 전국 수준에서 수집하여 보다 정밀한 모니터링이 이루어질 필요가 있다고 사료된다.

This study aimed to establish a marker compound in roasted Astragalus membranaceus (AM) water extract and to validate its analytical methods. The roasting process significantly enhanced the isoflavone content in AM. Among the four isoflavones analyzed, calycosin 7-glucoside (C7G) emerged as the most abundant, with a concentration of 847.88 μg/g in the AM extract. Due to its concentration and representativeness, C7G was designated as the marker compound, and its analytical method was thoroughly validated. Specificity was confirmed by the consistent retention time of the C7G peak at 15.2 minutes across both the sample and the standard compound. High absorbance was recorded at UV wavelengths of 220, 250, and 260 nm. The method exhibited excellent linearity, with a correlation coefficient (R2) of 0.9999 across a concentration range of 0.2 to 50.0 μg/mL. The limits of detection and quantification were determined to be 0.029 μg/mL and 0.088 μg/mL, respectively. Precision assessments revealed intra-day and inter-day variations of 0.812% and 1.650%, respectively. Recovery tests yielded values ranging from 99.419% to 104.861%, with relative standard deviations between 1.152% and 2.215%. These results affirm that the analytical method for C7G is highly specific, linear, accurate, and precise. This validated method may serve as a valuable tool for the standardization of roasted AM water extract.

Microalgae are efficient fatty acid producers owing to their high photosynthetic activities. They can act as sources of biofuel, feed, and various bioactive compounds. This study aimed to determine optimal culture conditions, including culture medium, temperature, and light intensity, to enhance the biomass and fatty acid content of the indigenous freshwater microalga, Tetradesmus obliquus. Evaluation using a high-throughput photobioreactor revealed that the optimal culture temperature and light intensity were 25°C and 300 μmol m-2 s-1, respectively. Additionally, we optimized components (N, P, and Mg) of the BG-11 medium to enhance the microalgal biomass. Modified BG-11 medium increased the T. obliquus biomass by 37% compared to the standard BG-11 medium. Subsequently, the culture medium was replaced with N- and P-depleted media to determine the abiotic stress factor that could increase the cellular fatty acid content. Notably, fatty acid content was significantly increased from 8.5% up to 14.6% on day 7 of culture in N-deficient (N-P+ and N-P-) media. Sequential optimization effectively increased the biomass by 83% and fatty acid content by >76% in T. obliquus. Our optimization method can be used to enhance the biomass and fatty acid contents of various other microalgae.