Food webs have received global attention as next-generation biomonitoring tools; however, it remains challenging because revealing trophic links between species is costly and laborious. Although a link-extrapolation method utilizing published trophic link data can address this difficulty, it has limitations when applied to construct food webs in domestic streams due to the lack of information on endemic species in global literature. Therefore, this study aimed to develop a link extrapolation-based food web model adapted to Korean stream ecosystems. We considered taxonomic similarity of predation and dominance of generalists in aquatic ecosystems, designing taxonomically higher-level matching methods: family matching for all fish (Family), endemic fish (Family-E), endemic fish playing the role of consumers (Family-EC), and resources (Family-ER). By adding the commonly used genus matching method (Genus) to these four matching methods, a total of five matching methods were used to construct 103 domestic food webs. Predictive power of both individual links and food web indices were evaluated by comparing constructed food webs with corresponding empirical food webs. Results showed that, in both evaluations, proposed methods tended to perform better than Genus in a data-poor environment. In particular, Family-E and Family-EC were the most effective matching methods. Our model addressed domestic data scarcity problems when using a link-extrapolation method. It offers opportunities to understand stream ecosystem food webs and may provide novel insights into biomonitoring.
We investigated the spatial distribution of heterotrophic bacteria associated with different water masses in the northern East China Sea (ECS) in summer. The surface water masses were divided into the Changjiang Diluted Water (CDW) and high salinity water (HSW). In the CDW region, the concentrations of dissolved inorganic nitrogen (DIN) and chlorophyll-a (Chl-a), and micro Chl-a contribution were high; and bacterial abundance (BA) and ciliate abundance (CA) were also high. In the HSW region with relatively low DIN concentrations, Chl-a concentration and micro Chl-a contribution were low, but pico Chl-a contribution was increased compared to those in the CDW region. BA did not show any significant difference from the CDW region, but CA was decreased. BA showed a positive correlation with Chl-a concentration in the CDW region; however, it did not show a significant correlation with Chl-a concentration in the HSW region. The ratio of bacterial carbon biomass/phytoplankton carbon biomass was exponentially increased with a decrease in the Chl-a concentration. Compared to the past (1990-2000s), the surface phosphate concentrations and the size of dominant phytoplankton have recently decreased in the ECS. Considering this trend of nutrient decrease and miniaturization of the phytoplankton, our results indicate that changes in the strength of the oligotrophic water mass could alter the function of the microbial food web.
Interactions between species in a community are very complex, and they are visualized and analyzed through a food web in simple way. Food web is a network of species connected by trophic links showing energy flow from prey to predator. Various models were developed to characterize the food web in ecosystems. In this study, we classified food web models to static models such as Ecopath and dynamic models such as AQUATOX. We presented characteristics of several different types of food web models in each category, and reviewed their applications used in aquatic ecosystems. Finally, we presented issues to be considered to develop food web models.
The purpose of study was to examine the factors influencing fast food consumption in Korean adolescents. The analysis was conducted using cross sectional study data from the 16th Korea Youth Risk Behavior Web-based Survey in 2020. A total 54,948 middle and high school students participated in this study. The subjects in the analysis were 28,353 males and 26,595 females, 28,961 middle school and 25,987 high school students. In total, 56.6% Korean adolescents consumed fast food once or twice weekly and 25.4% consumed fast food more than three times weekly. Logistic regression analysis revealed that fast food consumption was significantly associated with dietary behavior such as lower breakfast intake (OR: 0.930, 95%CI: 0.891~0.970, p<0.001), higher soda drinks consumption (OR: 2.563, 95%CI: 2.452~2.678, p<0.001), and higher sweet drinks consumption (OR: 1.898, 95%CI: 1.818~1.982, p<0.001). For psychological and health behavior factors, fast food consumption was also significantly associated with higher perceived stress (OR: 1.239, 95%CI: 1.163-1.321, p<0.001), higher smoking (OR: 1.300, 95%CI: 1.164~1.453, p<0.001), higher drinking (OR: 1.193, 95%CI: 1.112~1.280, p<0.001), higher depression experience, higher loneliness experience, and lower subjective health, In conclusion, fast food consumption in Korean adolescents was associated with undesirable dietary habits and psychological and health behavior, suggesting that appropriate education programs are necessary to reduce such behavior.
Tis study was an attempt to systematically analyze the characteristics of modern Korean food styling using the menu image photos of the Michelin Guide Seoul 2020 restaurants. The first sampling was conducted on the 27th of March 2020 and the second on the 27th of October 2020. A collection of images on the web and 442 photographic cases obtained by a search through theoretical background literature and research papers were studied by a qualitative analysis method. First, the food styling contents were analyzed and based on that, the food styling characteristics of the menus of 11 restaurants in Korea including the contemporary restaurants were considered. The analysis revealed several aspects of Korean food styling. First, food styling appeared to have three major characteristics: color, shape, and container styling. Color styling was further subdivided into single color/similar color, color contrast, source type, and accent color type. The shape/formative styling was classified into figure type, shape type, accessory type, and garnish type, and container styling was categorized as container color type, container shape type, and container material type. Second, the modern Korean food color styling characteristics of Michelin restaurants were categorized in the order of monochromatic/similar type, sauce type, accent color type, and color contrast. In the formative styling category, it was categorized in the order of shape type, small piece type, garnish/garnish type, and figure type. In container styling, container material type and formative type accounted for the major portion of the category. The food styling characteristics of the modern Korean menu were systematized and image examples were presented visually. Please use it as food styling educational material or personal food styling skill.
본 연구는 2019년 8월 한반도 주변해역(동해, 서해, 남해, 동중국해)에서 탄소 및 질소 안정동위원소 기법을 활용하여 하위영양 단계에서의 먹이망 구조를 파악하였다. 입자성 유기물(POM)의 δ13C 범위는 -26.18 ~ 20.61 ‰, δ15N 범위는 5.36 ~ 15.20 ‰의 넓은 범위를 보였다. POM과 각 생물별 개체군 사이의 δ13C 분별작용의 결과는 대부분 micro-POM을 섭식하는 것으로 확인하였으나 해역 간 차이를 보였 다. 각 생물별 영양단계는 chaetognaths (3.40±0.61)가 가장 높은 영양단계에 있음을 확인하였다. 동위원소 혼합모델을 적용한 결과에서 chaetognaths의 먹이원으로 copepods (13 ~ 48 %)와 euphausiids (20 ~ 51 %)가 가장 높은 기여도를 나타냈다. 본 연구결과 각 해역별 먹이원의 제한적 공급 및 다양성의 차이가 먹이망 구조 및 각 생물별 동위원소 비에 영향을 미친 것으로 판단된다.
Recently, quantitative analyses of food web structure based on carbon and nitrogen stable isotopes are widely applied to environmental assessments as well as ecological researches of various ecosystems, particularly rivers and streams. In the present study, we analyzed carbon and nitrogen stable isotope ratios of POM (both planktonic and attached forms), zooplankton, benthic macroinvertebrates and fish collected from 6 sites located at Nakdong River. Samples were collected from upstream areas of 5 weirs (Sangju, Gangjeong- Goryeong, Dalseong, Hapcheon-Changnyeong, and Changnyeong-Haman Weirs) and one downstream area of Hapcheon-Changnyeong Weir in dry season (June) and after rainy season (September). We suggested ranges of their carbon and nitrogen stable isotope ratios and calculated their trophic levels in the food web to compare their temporal and spatial variations. Trophic levels of organisms were relatively higher in Sangju Weir located at upper part of Nakdong River, and decreased thereafter. However, the trophic levels were recovered at the Changnyeong-Haman Weir, the lowest weir in the river. The trophic level calculated by nitrogen stable isotope ratios showed more reliable ranges when they were calculated based on zooplankton than POM used as baseline. The suggested quantitative ecological information of the majority of biological communities in Nakdong River would be helpful to understand the response of river food web to environmental disturbances and can be applied to various further researches regarding the quantitative approaches for the understanding food web structure and function of river ecosystems as well as restoration.
The long-term biological monitoring data in domestic streams need to be appropriately analyzed. Food-web analysis using network-based approach can give ecological implications on these kinds of data by including interactions between species. The purpose of this study is constructing food-webs as a preliminary step of the analysis. We used observed species list data for 8 years (2008-2015) provided in Water Information System (WIS), focusing cheonggye streams as a case study. On the basis of species interaction dataset extracted from Global Biotic Interactions (GloBI) database, 96 food-webs were constructed. In further studies, these food-webs could be analyzed in various ways such as static, dynamic and spatial approaches.
Understanding biotic interactions is important to illustrate ecological functions of stream environments. The purposeof this study is to compare the ecological functions of natural and artificial streams. For linking species, we used bioticinteraction databases and made food-webs for species lists of 18 streams in Seoul, Korea. We conducted species removalanalysis of networks and compared network beta-diversity between watersheds. The results showed that natural streamswere more affected by a removal of keystone species than artificial streams. The cheonggye watershed including artificialstreams had high dissimilarities among streams, presenting that artificial streams had different functions from natural streams.
Fish community was investigated in eutrophic Jeondae agricultural reservoir from April to November 2012. The food web structure of major fish species of Jeondae reservoir showed that due to serious organic pollution, thehyper-eutrophic condition with high chemical oxygen demand (COD), chlorophyll-a (Chl-a), total nitrogen (TN) and total phosphorus (TP), as estimated by stable isotope analysis. Total of 679 individuals were collected from the reservoir, and 9 species were identified. Interestingly, Lepomis macrochirus and Hemiculter eigenmanni known as less sensitive to pollution and water quality deterioration, dominated the reservoir, and their relative abundances were 38% and 27%, respectively. Further, the analysis of the stomach contents revealed that main food source of dominant L. macrochirus was high amount of zooplankton, which includes copepoda and cladocera, while Cyprinidae species mainly consumed organic particles with zooplankton preys. Stable isotope analysis also suggested that L. macrochirus, Carassiusauratus, Pseudorasboraparva, and H. eigenmanni are major zooplantivorous group in the Jeondae Reservoir.
주변 토지 이용이 다른 소부당과 명동저수지의 수변부 와 개방수역간에 동물플랑크톤 군집 분포와 먹이망을 파 악하기 위해 2011년 5월부터 10월까지 조사를 수행하였 다. 소부당과 명동저수지의 동물플랑크톤은 각각 51종, 65종이 출현하였으며, 수변부와 개방수역간에 뚜렷한 밀 도 차이를 보였다(t-test, P⁄0.05). 지각류와 요각류는 수 변부에서 높은 밀도를 보인 반면, 윤충류는 개방수역에서 더 높은 밀도를 나타냈다(t-test, P⁄0.05). 수변부에서 출 현한 동물플랑크톤 종은 주로 부착성 성향을 가진 종이 었다(Lecane, Monostyla, Alona 그리고 Chydorus). Chl.a 의 농도가 높은 명동저수지에서는 부유성 윤충류(Brachionus, Keratella 그리고 Polyarthra)의 높은 밀도가 관찰 되었다. Two-way ANOVA 결과, 윤충류는 서식처의 특성 과 토지 이용이 다른 두 저수지간에 뚜렷한 차이를 보인 반면, 지각류와 요각류는 서식처의 특성에만 의존하는 것 으로 나타났다. 저수의 영양상태가 주변 토지 이용과 밀 접하게 연관되는 점을 감안하면, 윤충류는 서식처의 특성 뿐만 아니라 저수지의 영양상태에 따른 먹이자원에도 밀 접하게 연관되는 것으로 보인다. 그러나 지각류와 요각류 는 먹이자원보다 서식처의 특성에 주로 영향받는다. 안정 동위원소 분석 결과, 부유성 Chl.a의 높은 값에도 불구하 고 동물플랑크톤은 주로 부착입자 유기물에 대해 의존하 였다. 이것은 실잠자리 유충, 검정물방개 그리고 새뱅이 같은 무척추동물과의 먹이 경쟁을 피하기 위한 것으로 사료된다. 결과적으로 동물플랑크톤 군집 분포는 습지의 공간적 특성 및 먹이자원에 의해 결정되는 것으로 보인 다. 흥미로운 점은 동물플랑크톤 군집 밀도를 결정하는 수생식물이나 식물플랑크톤 등은 수체 내의 영양염류의 농도에 영향받으며, 이는 습지 주변 토지 피복이 매우 중 요하게 고려된다는 것이다.
Recently, an integrated approach in insect ecology that including development of biological models and estimation of various effects using a logical model has become important. Through the biological components of ecosystem having complex temporal and spatial patterns, and complicated interactions of biotic and abiotic factors, dynamic models can be useful tools to investigate the whole ecosystems. Pollutants in terrestrial ecosystem can be transferred to insect body through insect’s sucking plant tissue, and effect on their biological properties. Trend of pollutants transfer from soil to plant root can be estimated using free ion activity model (FIAM), and distribution and accumulation in plant parts can be described by dynamic model with water potential, water translocation, and transfer rate. Biological response of plant and insect can be illustrated the dynamics model based on experiment data. The combination of these models show an overall behavior of toxicant and the interaction between plant and insect with time. The objectives of the research are to comprehensively analyze the transfer and effects of pollutant in soil, plant and insect system and to develop the assessment technique for soil ecosystem using dynamic modelling concerning the causal relationship and feedback processes. We are aimed specifically at prediction and assessment of various polluting scenarios of soil ecosystem through data collection from laboratory and field investigation, modelling and evaluation using module software programing.
동물플랑크톤의 서식 형태에 따른 구분(부착 및 부유 성)과 월별 밀도 양상을 파악하기 위해 2011년 5월부터 10월까지 수생식물이 발달된 환경에서 동물플랑크톤 채 집을 수행하였다. 조사 기간 동안, 부착성 동물플랑크톤 은 총 24종, 부유성 동물플랑크톤은 총 30종으로 나타났 으며, 이 중 두 서식 형태 간에 일치하는 종은 20종으로 확인되었다. 부착성 동물플랑크톤은 5~7월 동안 높은밀도를 나타낸 반면, 부유성 동물플랑크톤은 9~10월 동 안 높은 밀도를 보여 상이한 계절적 차이를 보였다. 안정 동위원소 분석 결과, 부착 및 부유입자 유기물, 동물플랑 크톤, 어류의 δ13C와 δ15N 값은 계절별로 상이하였다. 부 착성 동물플랑크톤은 봄, 가을 모두 부착입자 유기물에 대한 높은 의존도를 보였으나, 가을에는 부유입자 유기물 에 대해서는 일부 의존하는 것으로 나타났다. 이는 수생 식물의 우점 등으로 인한 먹이질의 감소와 연관되어 있 을 것으로 사료된다. 그러나 부유성 동물플랑크톤은 봄과 가을 모두 부유입자 유기물에 대해서만 의존하는 것으로 나타났다. L. macrochirus는 크기에 따라 먹이원에 대한 다른 섭식 양상을 보였는데, 부착성 동물플랑크톤이 증가 된 시기(봄)에 1~3 cm 크기의 L. macrochirus는 부착성 동물플랑크톤에 대한 높은 의존도를 보였으나, 가을에 부 착성 동물플랑크톤 감소하자 부유성 동물플랑크톤에 대 한 의존도가 높아지는 것을 확인할 수 있었다. 4~7 cm 크기의 L. macrochirus는 상대적으로 큰 먹이원인 부유 성 동물플랑크톤에 높은 의존도를 보였으며, 가을에 부유 성 동물플랑크톤 밀도가 증가하자 매우 높게 의존하는 것으로 나타났다. 결론적으로 습지와 같이 수생식물이 우 점되는 생태계에서 동물플랑크톤은 다양한 서식 형태(부 착 및 부유성)를 가진 군집이 출현하는 것으로 파악되었 으며, 이들은 각각 다른 먹이원에 대해 의존하는 것으로 나타났다. 또한 상위포식자인 L. macrochirus 또한 부착 및 부유성 동물플랑크톤의 계절별 밀도 양상에 따라 상 이한 의존성을 보였으며, 특히 부착성 동물플랑크톤은 봄 철 치어 성장 시기의 이들의 성장 및 발달에 매우 중요 한 영향을 미치는 것으로 사료된다.
Food web of main arthorpods in 3 differently managed rice fields (low input, duck, apple snail farming) was investigated in Hongseong area, Chungcheongnam-do, Korea. Main arthropods were selected by their abundance during the rice growing season in 2010. Food web was analyzed with stable isotope, δ15N and δ13C according to rice growth satges (seedling, tillering, booting, blooming/heading, and ripening stage). Rates of δ15N and δ13C in soil (F=5.72; df=2, 6; P=0.0407, F=40.86; df=2, 6; P=0.0003, respectively) and δ13C in rice (F=6.46; df=2, 6; P=0.0319) were statistically different. Rate of δ13C in Lissorhoptrus oryzophilus (F=9.50; df=2, 6; P=0.0138), Pirata subpiraticus (F=11.00; df=2, 6; P=0.0098), and Pachygnatha clercki (F=6.33; df=2, 6; P=0.0333) were statistically different among farming methods. Stable isotope structures in food web were slightly different among 3 farming methods seasonally. Rates of δ15N and δ13C of rice pests such as Nephotettix cincticeps, Nilaparvata lugens, Laodelphax striatellus, and Sogatella furcifera were related to rice plant. Those of Tomoceridae sp. and Chironomidae sp., however, were not related to rice plant. Spiders as main natural enemy group were ranked on the top of food web and were thought to have life cycle based on the rice field from stable isotope structure.
조사지점인 구포에서 발생한 규조류인 Stephanodiscus 속에 의한 수화현상은 본 연구 시점인 1월부터 관찰되었으며 4월 18일을 기점으로 감소하기 시작한 것으로 나타났다. 박테리아 군집은 규조류 대증식 현상이 소멸한 이후 증가하는 양상을 나타내었다. 이것은 규조류 수화현상이 종결되면서 조류에 의한 분비물 및 세포 분해 산물(cell lysis)이 수중에 많이 공급되어 박테리아 증식이 용이해졌기 때문으로 여겨진다. 박테리아의 주요 포식자로 알려진
This study developed learning content and web pages providing information on Health/Functional Food (HFF) for consumers who come across information indiscriminately from a variety of advertising media such as the Internet and TV. After coming to an understanding of the current situation through literature review and fact-finding, we collected information and commercials on HFF that are exposed to consumers. Focusing on advanced countries such as the U.S. and Japan, we examined the current status of consumer education programs, especially in terms of HFF industry. Further, we referred to the guidelines for consumer education provided by the U.S. Food and Drug Administration and monitored the information from a web site that sells dietary supplementary products in the U.S. In addition, we surveyed consumer information on foods for special health use provided by the Japanese National Institute of Health & Nutrition, and investigated a DB of raw materials of function food (functionality/safety documents). Upon a literature review, the 13 functions of HFF were classified. As a result of conducting interviews with consumers, we developed content that was fit for consumers’ perspectives. Through this research, we established a web page to enable people to search for information by function and then by raw material. After searching for information by raw materials, searching products by raw materials can be done in cooperation with E-marketplace. Subsequently developed content and education programs were offered on an HFF web page, which has been in operation since 2005. Therefore, it is expected that appropriate information on HFF will be available.
This study examined the effects of Web ad components on customer attitude and purchasing decisions in 300 individuals who visited family restaurant Websites. The results are summarized as follows: First, Web ad components such as content, design, and interactivity had effects on the cognitive attitudes of the customers. And design, accessibility, and Web functionality had significant effects on the customers' emotional attitudes. In addition, content, navigation, and Web functionality had significant effects on the customers' behavioral attitudes. Lastly, the cognitive, emotional, and behavioral attitudes of the customers had significant effects on their purchases. From these results, design elements such as content, color, and menus, along with user interactivity for information are considered helpful components of a food service Web ad for customer cognition of the restaurant's information. In addition, aspects of Web functionality such as the food service's Web ad set-up, or the protection of personal information, the color design and menu, as well as accessibility for easy use, are all helpful in terms of gaining a customer attitude that is friendly and preferential towards a restaurant's menu items.