간행물

Korean Journal of Environmental Biology KCI 등재 환경생물

권호리스트/논문검색
이 간행물 논문 검색

권호

Vol.42 No.4 (2024년 12월) 28

21.
2024.12 구독 인증기관 무료, 개인회원 유료
Current investigations provide a comprehensive understanding of the occurrence and biodiversity of plant-parasitic nematodes (PPNs) in the major citrusproducing regions of Jeju Island, South Korea. Our survey identified five genera and five species of PPNs from 82 infested Citrus unshiu field samples collected across 116 sites in the Jeju provinces. Community analysis revealed the highest prevalence of PPNs (39.02%) at Namwon-eup, significantly driven by Tylenchulus semipenetrans, followed by Paratylenchus sp., Helicotylenchus sp., Meloidogyne sp., and Pratylenchus sp. Data indicate that all 82 sites were infested with T. semipenetrans (70.68%), marking a considerable increase in prevalence compared to previous surveys and posing a significant threat to citrus cultivation. The study results also demonstrate the influence of soil type on PPNs communities, revealing correlations between soil texture and nematode diversity. Citrus orchards cultivated in black clay loam soil exhibited significant PPN infestations. Overall, the PPN survey underscores the economic importance of monitoring citrus nematode infection rates and maintaining economic threshold levels in citrus production. It also emphasizes the need for developing effective management strategies to control PPNs, which are essential for maintaining crop yield and ensuring agricultural sustainability.
4,200원
22.
2024.12 구독 인증기관 무료, 개인회원 유료
Biodiversity encompasses species diversity, which includes species richness and species evenness. High species diversity is known to contribute to community stability and the potential for maintaining healthy ecosystem functioning. However, the most commonly used species diversity indices have some limitations, as they require species-specific abundance data for each community. In contrast, phylogenetic diversity measures the evolutionary distances between species within a community, reflecting ecological and/or evolutionary divergences and niche differences, without requiring abundance data. This study assessed biodiversity by calculating phylogenetic diversity indices for freshwater fishes (19 species) and aquatic insects (49 species) at three sites within Seoraksan and Odaesan National Parks. The aquatic insects studied belong to the EPT group (Ephemeroptera, Plecoptera, and Trichoptera), which are widely used as bioindicators of aquatic ecosystems. Two mitochondrial DNA genes were used as molecular markers: COI and cyt b for fish, and COI and 16S rRNA for the EPT - group. Overall, Odaesan National Park exhibited higher phylogenetic diversity in both fishes and aquatic insects compared to Seoraksan National Park, although this difference was not statistically significant. The highest phylogenetic and species diversity were observed for fish at the OD2 site (Woljeong District) and for the EPT group at the OD1 (Gyebangsan) and SA2 (Jangsudae) sites. Correlation analysis revealed that phylogenetic diversity indices were more positively associated with species richness than species diversity indices. This study serves as a pilot project for establishing standardized methods for assessing biodiversity in national park habitats using phylogenetic diversity. It also aims to inform various policies, such as the development of biodiversity assessment systems and the prioritization of protected areas within national parks.
4,900원
23.
2024.12 구독 인증기관 무료, 개인회원 유료
The Pieris napi-complex in East Asia that comprises P. melete Ménétriés, 1857, P. dulcinea (Butler 1882), and P. nesis (Fruhstorfer 1909) has been taxonomically challenging to distinguish due to their similar appearances. In this study, P. nesis, typically found in central Japan, was discovered in the highlands on Jejudo Island, the southernmost part of the Korean Peninsula. We conducted a molecular phylogenetic analysis using mitochondrial COI gene to explore the relationship between P. dulcinea and P. nesis, and confirmed that P. nesis occurs in Korea. This paper provides the morphological characteristics of P. nesis compared to P. dulcinea, along with DNA data.
4,000원
24.
2024.12 구독 인증기관 무료, 개인회원 유료
Strains of epiphytic and toxic dinoflagellates were collected from the seawaters surrounding Ulleungdo and Dokdo islands in Korea, and their morphology, molecular phylogeny, and toxicity were analyzed. Each dinoflagellate strain was examined under a microscope for genus-level identification, while species-level confirmation was achieved for Amphidinium operculatum, Ostreopsis sp. (type 1), Protoceratium reticulatum, Coolia canariensis, and C. malayensis through molecular phylogenetic analysis. The genera Gambierdiscus, Heterocapsa, and Prorocentrum were identified based on morphological traits, with Gambierdiscus characterized by a round-flattened shape with distinct thecal plates, Heterocapsa exhibiting a fusiform to oval shape, and Prorocentrum showing an oblong-to-ovate shape. Toxicity assessments for five species involved exposing Artemia salina nauplii to concentration-dependent extracts of the dinoflagellates. At a concentration of 100 ppm, P. reticulatum, A. operculatum, C. canariensis, and Ostreopsis sp. resulted in significant mortality among the nauplii, with survival rates dropping to as low as 0% over a 24-hour period. These findings underscore the potential ecological and toxicological impacts of these species and highlight the necessity for further research to evaluate their behavior under varying environmental conditions. This study marks the first documentation of subtropical epiphytic dinoflagellates in the waters around Ulleungdo and Dokdo islands, encompassing twelve strains from eight epiphytic species. Additionally, we investigated the toxicity of five species, including a toxic planktonic dinoflagellate. The results suggest a potential northeastward shift in their distribution, likely originating from Jeju Island, and being transported by the Tsushima Warm Current through the East Sea. This shift has enabled the successful establishment of populations in these areas under favorable conditions influenced by changes in the oceanic climate.
5,100원
25.
2024.12 구독 인증기관 무료, 개인회원 유료
We have performed an experiment to evaluate the efficacy of salt and hot water treatments in soil for managing situations where high-risk plant-parasitic nematodes (PPNs) are detected in farms and flower shops that cultivate foliage plants. The density of Pratylenchus penetrans was reduced by 100% with salt treatments of 20 and 40 kg m-2, while decreases of 95% and 99.8% were observed with treatments of 5 and 10 kg m-2, respectively. In the hot water treatment, Pratylenchus penetrans decreased by 97.6% compared to the initial density. The salt treatment resulted in a decrease in pH and an increase in electrical conductivity (EC) compared to untreated soil. However, other characteristics, including organic matter content, available phosphorus, total nitrogen (T-N) rate, and exchangeable cations, did not differ from the control. In the case of hot water treatment, all properties were similar to those in the untreated group. As a result of this study, salt applications of more than 20 kg m-2 and hot water at 96°C could serve as effective control methods when high-risk PPNs are detected in flower shops and greenhouses located in urban or near-urban areas.
4,000원
26.
2024.12 구독 인증기관 무료, 개인회원 유료
This study investigated the spatial distribution of dissolved organic carbon and the changes in tidal flat soil characteristics following the flooding season in the closed estuary of the Geumgang River basin. We found that after the flooding season, a brackish water area expanded due to increased river discharge, which also introduced low concentrations of dissolved organic carbon from the river. Dissolved inorganic carbon predominantly originated from the sea in proportion to salinity, indicating that in the closed estuary area, dissolved carbon supplied from the sea remained a significant source even after the flooding season. Additionally, a substantial amount of tidally transported silt and clay was deposited near the estuary dam after the flood, and its effects continued to influence the sediment characteristics downstream in the intertidal zone. As an empirical study in the closed estuary, our results are expected to contribute to conservation measures for the World Heritage Site in the area.
4,000원
27.
2024.12 구독 인증기관 무료, 개인회원 유료
The Hangang River, serving as the primary water supply source for the capital region of South Korea, plays a vital role in sustaining regional ecosystems and ensuring water quality. Phytoplankton are integral to the maintenance of aquatic ecosystems and function as bioindicators of water contamination; however, the species-level composition and environmental interactions of phytoplankton in the Hangang River remain inadequately characterized. This study investigated the phytoplankton communities within the Hangang River system across eight sampling stations over eight sampling events from May 2021 to March 2022. A total of 71 species were identified, yielding a density of 3,560 cells mL-1, with Bacillariophyceae (36 species, 2,809 cells mL-1), Chlorophyceae (24 species, 212 cells mL-1), and Cyanophyceae (5 species, 394 cells mL-1) identified as the dominant groups. The most abundant species was Aulacoseira granulata (1,616 cells mL-1, 45.4%), followed by Stephanodiscus hantzschii (420 cells mL-1, 11.8%) and Phormidium tenue (383 cells mL-1, 10.8%). Spatial similarity analysis of the phytoplankton communities revealed three distinct groups: Group A (stations 1-4, upstream), Group B (stations 5-7, midstream), and Group C (station 8, downstream). Seasonal similarity analysis further categorized the communities into three groups: Group A (May, July, August, and October 2021), Group B (November and December 2021), and Group C (February and March 2022). These findings contribute to a deeper understanding of the spatial and seasonal dynamics of phytoplankton in the Hangang River system.
4,600원
28.
2024.12 구독 인증기관 무료, 개인회원 유료
The present study was undertaken to ascertain the temperature development characteristics of Phthorimaea operculella (Lepidoptera: Gelechiidae) across its various developmental stages. To this end, the insect was subjected to six constant temperature conditions (13, 17, 25, 27, 32, 34±1°C), relative humidity (RH) levels of 65±5%, and photoperiods of 16 : 8 h light/dark. The developmental time of larvae was longest at 13°C, and as the temperature increased up to 35°C, the developmental time tended to become shorter. At the pupal stage, all individuals developing at 13°C perished and were excluded from the calculation of the development period for the development model. To ascertain the relationship between temperature and development, a regression model was employed for analysis. The lower threshold temperature of the total immature stage was determined to be 9.4°C, and the thermal constant was found to be 454.5DD. In the analysis of the temperature-development experiment, the Lactin 2 model exhibited an optimal fit (R 2=0.90-0.98) for the total immature stage of P. operculella.
4,000원
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