This study utilizes association rule learning and clustering analysis to explore the co-occurrence and relationships within ecosystems, focusing on the endangered brackish-water snail Clithon retropictum, classified as Class II endangered wildlife in Korea. The goal is to analyze co-occurrence patterns between brackish-water snails and other species to better understand their roles within the ecosystem. By examining co-occurrence patterns and relationships among species in large datasets, association rule learning aids in identifying significant relationships. Meanwhile, K-means and hierarchical clustering analyses are employed to assess ecological similarities and differences among species, facilitating their classification based on ecological characteristics. The findings reveal a significant level of relationship and co-occurrence between brackish-water snails and other species. This research underscores the importance of understanding these relationships for the conservation of endangered species like C. retropictum and for developing effective ecosystem management strategies. By emphasizing the role of a data-driven approach, this study contributes to advancing our knowledge on biodiversity conservation and ecosystem health, proposing new directions for future research in ecosystem management and conservation strategies.
In this study, we investigated the microbial community of oyster mushrooms at different growth stages at the species level. Gram-positive bacteria were predominant in the presterilized medium. On the other hand, Gram-negative bacteria were predominant in the culture-completed medium, post-harvest medium, and fruiting bodies. In addition, Pseudomonas tolaasii, which is known to cause disease in mushrooms, was confirmed in the cultured medium, post-harvest medium, and fruiting bodies, and it was determined that the mycelium culture stage was contaminated, and the reason why no disease occurred was Sphingobacterium psychroaquaticum. It was confirmed that this was because the growth of Pseudomonas tolaasii was suppressed by producing a component called tolacin. As a result of confirming the diversity of microorganisms, it was confirmed that the presterilization medium contains a variety of microorganisms compared to other growth stages, and the diversity decreases in the order of culture completion medium, fruiting body, and post-harvest medium. showed a trend. As a result of microbial similarity analysis, it was confirmed that the cultured medium and the post-harvest medium showed similar microbial communities, and in the case of fruiting bodies, there were some similarities but overall differences.
Fish resource surveys were conducted near Jeju Island in June, August and October 2021 using an underwater camera monitoring system, fish pots, and SCUBA diving methods. The efficiency of the methods used to survey fish resources was compared using the number of individuals compared to area per unit time (inds/m3/h) and the number of species compared to area per unit time (spp./m3/h). As a result of comparing the number of individuals compared to the area per unit time (inds/m3/h), the order was underwater camera 214.69, SCUBA diving 124.62, and fish pots 0.57 inds/m3/h. The number of species compared to area per unit time (spp./m3/h) is in the following order: SCUBA diving 0.85, underwater camera 0.38, and fish pots 0.01 spp./m3/h. The fish resource monitoring method using underwater cameras was found to be more efficient in individual counts, and the SCUBA diving method was found to be more efficient in species counts. When considering cost and survey efficiency, the fish resource survey method using underwater cameras was judged to be more effective. The results of this study are expected to be widely used in estimating the population density of fish, which is the core of future fisheries resource surveys.
A variation of fish assemblage in the coastal waters of Sagye-ri, southern Jeju Island was determined using samples collected by trammel net from 2012 to 2022. The total fish species caught by trammel net were identified 88 species, 46 families, 12 orders, and the number of appearance and biomass were 3,479 individuals and 883.6 kg. The annual variation of species was the highest in 2013 at 46 species and the lowest in 2021 at 30 species. The seasonal variation of species was higher in summer at 67 species and lower in winter, autumn at 47 species. The annual diversity index, evenness index, and richness index were appeared 2.42-3.00, 0.69-0.78 and 5.18-7.24 at each years. The dominance index appeared highest in 2013 and the lowest in 2018. Cluster analysis based on the number of individuals of fish was classified into two groups at the dissimilarity level of 57%, and results of SIMPROF analysis revealed significant differences in community structure among the two groups. The subtropical fishes were identified a total of 42 species (47.7%) and the number of species was higher in 2013 at 25 (54.3%) species and lower in 2018 and 2021 at each 17 (54.8~56.7%) species. The dominant species of subtropical fishes were appeared rabbit fish (Siganus fuscescens), scarbreast tuskfish (Choerodon azurio), bluestriped angelfish (Chaetodontoplus septentrionalis), balloon fish (Diodon holocanthus), and flag fish (Goniistius zonatus) at study sites.
This study investigated the species composition and community structure of aquatic organisms captured using coastal beam trawling in Gomso Bay, Jeollabuk-do, from January to December 2022. Throughout the experimental period, a total of 20,246 individuals belonging to 94 marine species were captured, with a combined biomass of 602,828 g. Fish exhibited the highest abundance, comprising 56 species, followed by crustacea (21 species), bivalvia (8 species), cephalopoda (5 species), gastropoda (3 species), and holothuroidea (1 species). The dominant species was Leiognathus nuchalis, constituting 14.0% of the total individuals, followed by Portunus trituberculatus at 12.1%, Oratosquilla oratoria at 10.4%, Crangon hakodatei at 9.9%, and Metapenaeus joyneri at 7.9%. The diversity index ranged from 1.72 to 2.55, with the lowest diversity observed in March and the highest in July. Cluster analysis based on species composition of the 27 most common species showed that aquatic organisms were divided into three groups: spring and summer organisms (Group A) and summer organisms (Group B) and autumn and winter organisms (Group C).
안양천의 어류 군집 특성과 어류상에 대한 수질의 영향을 밝히기 위해 2022년 4~6월과 8~10월에 20개 지점을 2회 조사하였다. 조사 기간 동안 채집된 어류는 5목 10과 34종 3,186개체였다. 우점종은 피라미(Zacco platypus, 43.4%) 였고, 아우점종은 붕어(Carassius auratus, 10.1%), 그 다음으로 잉어(Cyprinus carpio, 7.6%), 참갈겨니(Zacco koreanus, 6.2%), 돌고기(Pungtungia herzi, 5.2%), 대륙송사리(Oryzias sinensis, 5.1%), 참붕어(Pseudorasbora parva, 4.7%), 긴몰개(Squalidus gracilis majimae, 4.4%), 버들치(Rhynchocypris oxycephalus, 3.5%), 치리(Hemiculter eigenmanni, 3.3%), 흰줄납줄개(Rhodeus ocellatus, 1.4%), 가숭어(Chelon haematocheilus, 1.0%) 등의 순으로 우세하 게 출현하였다. 출현종 중 한국고유종은 각시붕어(Rhodeus uyekii), 긴몰개, 몰개(Squalidus japonicus coreanus), 참갈 겨니, 얼록동사리(Odontobutis interrupta) 5종(14.7%)이었고, 외래종은 이스라엘잉어(Cyprinus carpio Israeli type), 블루길(Lepomis macrochirus), 배스(Micropterus salmoides), 구피(Poecilia reticulata) 4종(11.8%)이었다. 어류 군집 분석 결과, 우점도는 상류가 높았고 하류로 가면서 낮아졌으며, 다양도와 풍부도, 균등도는 본류보다 지류에서 높게 나타나는 경향을 보였다. 하천건강성을 평가한 결과, 7개 지점에서 보통(C), 8개 지점에서 나쁨(D), 5개 지점에서 매우 나쁨(E)으로 평가되어 좋지 않았다. 수질은 8개 지점을 평가한 결과, 4개 지점은 보통(III), 2개 지점은 나쁨(V), 1개 지점은 약간 나쁨(IV), 1개 지점은 약간 좋음(II)으로 평가되어, 전체적인 수질은 나쁘게 나타났으며, 수질이 하천건 강성과 어류의 서식에 큰 영향을 미치고 있는 것으로 추정되었다. 또한 안양천에 어도가 없는 보가 많이 설치되어 있어 어류의 이동에 장애물로 작용하고 있었다. 따라서 하천건강성을 높이고 안정적인 어류의 서식을 위해서는 수질을 개선할 수 있는 체계적인 관리방안이 필요하고 보에 어도 설치가 요구되었다.
Most wetlands worldwide have suffered from extensive human exploitation. Unfortunately they have been less explored compared to river and lake ecosystems despite their ecological importance and economic values. This is the same case in Korea. This study was aimed to estimate the assemblage attributes and distribution characteristics of benthic macroinvertebrates for fifty wetlands distributed throughout subtropical Jeju Island in 2021. A total of 133 taxa were identified during survey periods belonging to 53 families, 19 orders, 5 classes and 3 phyla. Taxa richness ranged from 4 to 31 taxa per wetland with an average of 17.5 taxa. Taxa richness and abundance of predatory insect groups such as Odonata, Hemiptera and Coleoptera respectively accounted for 67.7% and 68.2% of the total. Among them Coleoptera were the most diverse and abundant. Taxa richness and abundance did not significantly differ from each wetland type classified in accordance with the National Wetland Classification System. There were three endangered species (Clithon retropictum, Lethocerus deyrolli and Cybister (Cybister) chinensis) and several restrictively distributed species only in Jeju Island. Cluster analysis based on the similarity in the benthic macroinvertebrate composition largely classified 50 wetlands into two major clusters: small wetlands located in lowland areas and medium-sized wetlands in middle mountainous regions. All cluster groups displayed significant differences in wetland area, long axis, percentage of fine particles and macrophyte composition ratio. Indicator Species Analysis selected 19 important indicators with the highest indicator value of Ceriagrion melanurum at 63%, followed by Noterus japonicus (59%) and Polypylis hemisphaerula (58%). Our results are expected to provide fundamental information on the biodiversity and habitat environments for benthic macroinvertebrates in wetland ecosystems, consequently helping to establish conservation and restoration plans for small wetlands relatively vulnerable to human disturbance.
벽계천의 어류군집 특성 및 멸종위기 4종의 서식 양상을 밝히기 위해 2020년 4월부터 9월까지 조사를 실시하였다. 조사기간 동안 7개 지점을 선정하여 조사한 결과, 채집된 어류는 9과 31종 3,415개체였다. 출현종 중 우점종은 참갈겨니 (Zacco koreanus, 31.2%), 아우점종은 피라미(Z. platypus, 15.0%), 다음으로 돌고기(Pungtungia herzi, 11.7%), 줄납자 루(Acheilognathus yamatsutae, 5.4%), 납자루(A. lanceolata intermedia, 4.8%), 밀어(Rhinogobius brunneus, 4.4%), 가는돌고기(Pseudopungtungia tenuicorpa, 4.3%) 등의 순으로 우세하였다. 출현종 중 한국고유종은 19종(고유화율 61.3%)이었고, 기후변화민감종(냉수성 어종)은 금강모치(Rhynchocypris kumgangensis)와 둑중개(Cottus koreanus) 2종이 확인되었다. 법정보호종은 환경부지정 멸종위기 야생생물 II급인 묵납자루(A. signifer)와 가는돌고기, 한강납줄 개(Rhodeus pseudosericeus), 둑중개 4종이 출현하였으며, 주로 묵납자루와 가는돌고기는 중·하류에, 한강납줄개는 중류에, 둑중개는 최상류에 서식하고 있었다. 이중 가는돌고기는 출현개체수가 가장 많았고, 전장빈도분포도로 연령을 추정한 결과, 7월기준 전장 24~35㎜는 당년생, 54~75㎜는 1년생, 82~97㎜는 2년생, 104~109㎜는 3년생 이상으로 추정되었다. 군집분석 중 우점도는 상류에서 높고 하류로 갈수록 낮아지는 경향을 보이나 다양도와 균등도, 풍부도는 상류에서 낮고 하류로 갈수록 높아지는 경향을 보였다. 하천건강성(FAI)은 매우 좋음 5개 지점, 좋음 2개 지점으로 나타나 양호하였다. 벽계천은 비교적 서식지가 잘 보존되고 있었으나 멸종위기종이 많이 서식하는 중·하류부 일부는 하천공사가 진행되면서 서식지가 교란되고 있어 보존대책이 요구되었다.
본 연구는 패류양식업이 밀집한 남해 강진만 해역에서 수하식 및 살포식 양식해역과 비양식해역을 구분하여 양식활동으로 인한 유기물 축적과 저서다모류군집 변화를 파악하고, 어장환경평가 기법을 활용하여 건강도를 평가하고자 수행되었다. 남해 강진만 해역의 평균 입도, 수온, 염분농도, 총유기탄소 등의 시·공간 분포는 정점간에 큰 차이가 없었던 반면, 출현 종수, 개체밀도와 종다양도 등은 살포식 양식 해역의 정점이 다른 해역의 정점과 비교해 상대적으로 낮은 경향을 보였다. 한편 집괴분석과 주요좌표분석 결과에서도 살포식 양식해역 정 점의 저서다모류군집이 나머지 정점의 군집과 뚜렷하게 구분되었다. 수하식 양식해역의 정점과 비양식해역 정점에서는 오염지시종인 Scolectoma longifolia와 Sigambra tentaculata가 우점종으로 출현하였으나, 수심과 해수 유통 등의 물리적인 요인에 의한 영향을 받는 일부 정점 을 제외하면 점유율이 높지 않았다. 강진만 해역의 저서생태계 건강도는 1~2등급으로 양호한 상태였다. 그러나, 다모류군집구조의 시·공간 분 포와 저서생태계 건강도지수를 고려하면 살포식 양식해역의 퇴적환경은 양식으로 인한 물리적인 교란에 영향을 받는 것으로 보여진다.
To understand the spatiotemporal distribution pattern of zooplankton and the environmental factors influencing zooplankton abundance in Gomso Bay, major harvesting area of Manila clam (Venerupis philippinarum) in South Korea, zooplankton sampling was conducted four times in autumn (October 2022), winter (January 2023), early spring (March 2023), and spring (May 2023). Among the environmental factors of Gomso Bay, water temperature, chlorophyll a concentration (Chl-a), dissolved oxygen (DO), and pH observed different patterns, while salinity and suspended particulate matter (SPM) showed no significant statistical differences between the survey periods. The zooplankton in Gomso Bay occurred 33, 29, 27, and 29 taxonomic groups during each respective survey period. In October 2022 and May 2023, arthropod plankton were dominated, while in January and March 2023, protozoa were primarily dominant. Among the Arthropods, copepods including Acartia hongi, Paracalanus parvus s. l., Corycaeus spp., and Oithona spp. commonly found along Korean coastal areas of the Yellow Sea, were dominated. Cluster analysis based on zooplankton abundance indicated a single community (stable condition) in each season, attributed to low dissimilarity distances, while three distinct clusters (autumn, winter-early spring, spring) between seasons indicated a highly seasonal environment in Gomso Bay.
This study investigated the diversity of butterfly communities inhabiting agroecosystems and examined the effect of latitude and longitude. The ecological characteristics of butterflies inhabiting rural ecosystems, such as habitat preference and food plant range, were also examined. This study was conducted from 2019 to 2022, selecting 10 locations nationwide and conducting line transect surveys every two weeks for four years, confirming a total of 112 species and 21,901 individuals. There was no difference in the number of species and individuals by region, but there was a clear difference in community composition. The most abundant species in rural ecosystems were Pieris rapae, Polygonia c-aureum, Zizeeria maha, and Colias erate, in that order. There was no significant difference in the number of species and individuals by latitude and longitude, indicating no peninsula effect. Habitat preference showed that butterflies preferring grasslands and forest edges were much more common than those preferring the forest interior, and the food breadth was mostly oligophagous, followed by monophagous and polyphagous. Butterflies inhabiting agroecosystems had ecological characteristics that preferred open spaces such as grasslands and forest edges or relatively diverse foods, due to the similarity of the environmental characteristics of the survey points. Through this study, we believe that continuous monitoring is necessary to determine whether climate change, which is currently underway and habitat change are affecting butterflies in agroecosystems.
River estuaries are dynamic and productive ecosystems with high regional biodiversity. Environmental DNA (eDNA) has become a useful approach to assessing biodiversity in aquatic ecosystems. This study was conducted to investigate fish community characteristics and species diversity in two river estuary ecosystems, the Taehwa River and Changwon Stream. We further compared conventional and eDNA metabarcoding analyses of the fish communities. The conventional survey was performed in May, July, and October 2022, while the eDNA analysis was conducted only in May. We observed various fish species with different life histories, including carp, goby, and marine fish. We also found that migratory fish, such as dace Tribolodon hakonensis, sweetfish Plecoglossus altivelis, and eel Auguilla japonica, occurred in the Taehwa River, suggesting high river connectivity. Marine fish species were predominant in the Changwon Stream, as this river is located close to the sea. The diversity indices showed that the Taehwa River generally had higher species richness, evenness, and diversity values than the Changwon Stream. A total of 9-19 species were detected in the conventional survey for the three sites, whereas 11-18 species were found from eDNA analysis. The findings indicate that the sensitivity of eDNA was similar to or higher than that of the conventional method. Our study findings suggest the efficiency and efficacy of eDNA-based fish community monitoring, although with some shortcomings in applying the genetic marker to Korean fish, including no clear-cut distinction for Korean endemic species and/or genetically closely related species groups.
This study conducted an investigation into the effects of fruit type and cultivation practices (organic and conventional) on soil characteristics and soil arthropod communities within apple, blueberry, grape, peach, and pear orchards. The collection of soil arthropod communities was achieved through the utilization of pitfall traps, with concurrent measurements taken for soil moisture content, electrical conductivity, and temperature. The findings of this study unveiled substantial impacts attributed to fruit type and cultivation practices on soil characteristics. Specifically, within organic apple orchards, discernibly higher levels of soil moisture content, electrical conductivity, and temperature were observed when compared to their conventional counterparts. The investigation into soil arthropod communities yielded a total of 1,527 individuals, classified in to five phyla and 15 orders. The range of abundance, species richness, and diversity indices varied across conventional and organic orchards. Cultivation practices were found not to exert a significant influence on soil arthropod community characteristics. However, Non-metric Multidimensional Scaling (NMDS) analysis indicated a significant differentiation in soil arthropod community structure based on cultivation practices. This study underscores the importance of considering vegetation structure and environmental characteristics that may influence soil arthropod communities comprehensively when assessing the impact of cultivation practices on soil arthropods. Furthermore, it emphasizes the need to account for both the characteristics and structure of soil arthropod communities in understanding the implications of cultivation practices on these organisms.
본 연구는 백두대간보호지역에 서식하는 포유류와 등산객의 일중 활동 주기의 비교를 통해 시간적 규모에 따른 포유류 군집의 잠재적 위험성 검증을 위해 수행되었다. 이를 위해 2015년부터 2019년까지 백두대간보호지역의 능선부 를 대상으로 무인센서카메라를 활용하여 등산객과 포유류의 활동 주기를 분석하였다. 조사 결과 담비와 다람쥐의 활동 주기는 연중 등산객의 활동 주기와 높게 중첩되었다. 또한, 노루와 고라니는 봄에 등산객의 활동 주기와 높게 중첩되며, 멧돼지는 겨울에 등산객의 활동 주기와 높게 중첩되었다. 삵과 너구리, 오소리의 일중 활동 주기는 전체기간 동안 등산객의 활동 주기와 중첩되지 않았다. 포유류의 일중 활동 주기는 종 특이적 행동 패턴과 계절에 따라 차이를 보이며, 그에 따라 등산객의 활동 주기와 중첩에 차이를 보였다. 종 특이적 행동 특성과 계절에 따른 행동의 차이로 인해 백두대간보호지역에 서식하는 포유류는 인간의 활동에 의한 간섭에 대한 영향은 차이가 발생할 것으로 예상된다. 본 연구 결과 백두대간보호지역에 서식하는 포유류의 종 특이적 행동 특성에 관한 기초자료의 제공과 더불어 종과 계절에 따른 포유류 군집의 안정성 확보를 위한 관리 및 보전 방안의 수립을 위한 기초자료로써 의미를 가진다고 판단된다.