5papers in this issue.
To identify the spatiotemporal distribution of organisms by detecting DNA fragments released into the environment, environmental DNA (eDNA) is readily employed. This technique is receiving significant attention in ecological research, particularly in aquatic ecosystems, as an effective alternative method for national monitoring systems that need to simultaneously investigate diverse biological communities at multiple sites, at low costs and technical discrepancies. However, challenges remain, such as improving poor reliability of genetic information databases, standardizing application of methods, and interpretating of acquired genetic information, including issues of false positives and false negatives. This study explores international cases in which eDNA methods have been actively developed and applied, and summarizes the current state of research in South Korea and the various issues identified in these studies to guide individuals and domestic institutions regarding the application of eDNA technology as a targeted investigation or supplementary tool for future biological surveys.
The development of urban areas threatens the Earth’s systems by damaging ecosystems and decreasing biodiversity, as well as contributing to climate change due to increased air pollution from transportation and industrial activities. Greening along streets can help mitigate climate change effects, making plant species selection crucial for greening programs. The suitability of a plant species can be understood by studying growth strategies through ecophysiological components analysis in leaves and stems. This study aimed to identify the ecophysiological characteristics of roadside trees in urban area for designing a sustainable urban greening strategy. Using this approach, we can understand the adaptation and performance of trees facing urban environmental pressures. Field observations or abiotic factor and laboratory analysis were employed to identify ecophysiological characteristics including specific leaf area (SLA), specific leaf weight (SLW), leaf dry matter content (LDMC), LA, leaf thickness, stomatal density, stomatal aperture, trichome density, chlorophyll content and wood density (WD). Analyses of important ecophysiological characteristics (LA, SLA, LDMC, and WD) showed that the trees could be grouped into non-native (Swietenia mahagoni, Samanea saman, Muntingia calabura, and Monoon longifolium) and native species (Mimusops elengi, Pterocarpus indicus, Ficus benjamina, and Syzygium myrtifolium). These results provide recommendations for tree species suitable for roadside planting based on ecophysiological performance data.
Various flies and beetles have been found decomposing corpses. These can be useful indicators in forensic entomology. In Korea, forensic entomological research is mainly conducted in the spring, summer, and fall. No studies have been conducted in winter. Therefore, we concluded that a comparative experiment is necessary. In this study, we compared the number of decomposition days and insect fauna found in water deer (Hydropotes inermis) carcasses between summer and winter in 2021 and 2022. Carcasses were placed in wire mesh cages to prevent the intrusion of wild animals. A time-lapse camera was installed to observe the decomposition process of the carcass, and insects found in the corpse were collected to confirm the seasonal insect fauna. Seasonal temperature-dependent changes in humidity were recorded. We found that winter carcasses decomposed longer than summer carcasses, and confirmed differences in their decomposition processes. We confirmed that different species of insects appeared first in summer and winter and identified differences in insects by season. Among the flies attracted to the carcasses, Lucilia and Calliphora were first identified in summer and winter, respectively. In addition, we confirmed that flies were attracted first during summer, and beetles were attracted first during winter. This highlights the need for field reconstruction to identify beetles during winter. Therefore, the indicator species to be applied in forensic entomology should vary depending on seasonal differences in temperature and humidity.
We isolated a highly pathogenic avian influenza A virus (HPAIV) H5N1 clade 2.3.4.4b, A/Northern Shoveler/Jeju/D60/2023, from a deceased shoveler in Jeju Island, South Korea, in December 2023. The isolate was genetically related to HPAIVs in North America and Japan, which have recently caused a pandemic. Phylogeographic analysis showed that the isolated H5N1 virus had a different origin compared to those recently reported in the mainland of South Korea, with the HA and NA gene segments closely related to those from Japan and North America, respectively. This finding highlights the multi-faceted introduction of the genetically distinct HPAIV H5N1 into South Korea and provides potential evidence of intercontinental transmission between North America and East Asia.
Invasive alien species are one of the five primary drivers of global biodiversity loss. This study aimed to document the first record of Mieniplotia scabra in South Korea aquatic ecosystems, discovered during the nationwide survey on the habitat status of invasive alien species. The Jukdang Stream in Icheon, Gyeonggi Province is a well-known habitat for various artificially released tropical ornamental fish due to the heated effluent discharge from a large semiconductor factory. A total of five specimens of M. scabra were collected from Jukdang Stream in Icheon, Gyeonggi Province, a well-known habitat for various artificially released tropical ornamental fish. The specimens were visually distinguished from native freshwater snails by their distinct dark red striped patterns and well-developed spines on the ribs. Genetic analysis, which was performed to verify the morphological characteristics, clearly confirmed that the species to be M. scabra. With its remarkable parthenogenetic reproductive ability and high environmental adaptability, M. scabra is likely to outcompete native species and possibly suppress their populations if it spreads further in the aquatic ecosystems of the country. Additionally, the species poses a significant health risk as a known intermediate host of the intestinal fluke Haplorchis taichui, which causes symptoms resembling to irritable bowel syndrome in humans. To confirm the establishment of M. scabra in South Korea, further monitoring of similar habitats with heated effluent inflow is necessary, and special precautions must be taken to avoid its consumption, since it could easily be mistaken for native snails.