• Title/Summary/Keyword: Occurrence ecology

Search Result 328, Processing Time 0.026 seconds

Longitudinal Variation of Fish Communities in the Geum River, Korea: Application of the Concept of Beta Diversity and Local Uniqueness

  • Kim, Jeong-Hui;Park, Sang-Hyeon;Baek, Seung-Ho;Hong, Donghyun;Jo, Hyunbin
    • Proceedings of the National Institute of Ecology of the Republic of Korea
    • /
    • v.3 no.2
    • /
    • pp.122-128
    • /
    • 2022
  • To present the spatial variation of fish assemblages in the Geum River in Korea, the concept of beta diversity (β-diversity) estimates based on the variance of the community data table was applied. Fish communities and environmental variables were collected from 13 sampling sites along the in mid-low reaches of the River. We calculated the β-diversity and local contribution to beta diversity (LCBD) values at each site depending on the two types of data, 'occurrence' with Jaccard and Sørensen dissimilarity coefficients, and 'abundance' with Hellinger distance. Multivariate and correlation analyses were also performed to determine the relationships between LCBD and other variables, such as community indices and physicochemical and hydrological factors. The β-diversity values of fish communities in the River were estimated as 0.218 and 0.145 for occurrence data table with Jaccard and Sørensen respectively, and 0.268 for abundance data. Similar patterns of LCBD along the sampling sites were detected in two dissimilarity measurements of occurrence table, and LCBD values with abundance data were slightly different. The LCBD values are strongly correlated with community indices, and also suitable for indicating the uniqueness of fish assemblages. However, further research is needed to determine the LCBD value as an indicator of environmental variability.

A Study on the Characteristics of Road-kills in the Odaesan National Park (오대산국립공원의 야생동물 로드킬 특성)

  • Min, Ji-Hong;Han, Gab-Soo
    • Korean Journal of Environment and Ecology
    • /
    • v.24 no.1
    • /
    • pp.46-53
    • /
    • 2010
  • The purpose of this study is to provide a database for the reduction of road-kills in the Odaesan National Park. To accomplish this task, investigations were conducted on the road-kills that occurred in the period from 2003 to 2007. The results of investigations are as follows: 427 road-kill cases were reported during the period, and the road-kill victims turned out to be mostly small mammals. Among mammals and reptiles the road-kill occurrence rate of squirrels and garters was higher than that of other species, and in the case of birds, the road-kill occurrence rate of yellow-throated bunting was the highest. The road-kill accidents of mammals and reptiles took place more frequently during the summer and autumn, while those of birds during the spring and summer. The increase of road-kill occurrence rate was found to be related to the activity and breeding period of wild animals, as well as to the increase of vehicles. The occurrence rate of road-kills was also found to be influenced by the type of land use on the roadside. Furthermore, the occurrence rate increased significantly when the roads passed through dry fields.

Environmental Factors Influencing on the Occurrence of Pine Wilt Disease in Korea (우리나라에서 소나무재선충병 초기 발생지의 환경 특성 분석)

  • Lee, Dae-Seong;Nam, Youngwoo;Choi, Won Il;Park, Young-Seuk
    • Korean Journal of Ecology and Environment
    • /
    • v.50 no.4
    • /
    • pp.374-380
    • /
    • 2017
  • Pine wilt disease (PWD) is one of the hazardous pine tree diseases in whole world. In Korea, PWD has been spreading since it was first observed in Busan in 1988. Dispersion of PWD is mainly mediated by its vectors such as Japanese pine sawyer. In this study, we characterized environmental condition including meteorological factors, geographical factors, and land use factors influencing on the occurrence of PWD. The occurrence data of PWD were collected at 153 sites where were the initial occurrence sites of PWD in local government regions such as city, Gun, or Gu scale. We used Akaike Information Criterion (AIC) to evaluate the relative importance of environmental variables on the discrimination of occurrence or absence of PWD. The results showed that altitude, slope, and distance to road were the most influential factors on the occurrence of PWD, followed by distance to building. Finally, our study presented that human activities highly influenced on the long term dispersal of PWD.

Occurrence and distribution of Cellular Slime Molds by Vegetation in Island Ulneungdo (울릉도에서의 세포성 점균의 출현과 분포)

  • 심규철;장남기
    • The Korean Journal of Ecology
    • /
    • v.21 no.4
    • /
    • pp.345-349
    • /
    • 1998
  • thirteen dictyostelid cellular slime molds were isolated from forest soils, cattle dung and manure inisland Ulneungdo, South Korea. They were ten species including Dictyostelium aureo-stipes var. aureo-stipes, D. brefeldianum, D. macrocephalum, D. caudabasis, D. sphaerocephalum, D. giganteum, D. crassicaule, Polysphondylium pallidum, P. violaceum and P. tenuissimum as well as three species unidentified. D. aureo-stipes var. aureo-species of genus Polysphondylium distributed widely. It was thought that species diversi쇼 was considerabley higher.

  • PDF

Desmids from Korea; 1. Desmidiaceae 1 (Micrasterias)

  • Kim, Han Soon
    • Journal of Ecology and Environment
    • /
    • v.37 no.4
    • /
    • pp.285-298
    • /
    • 2014
  • The present study summarizes the occurrence, distribution and autecology of the genus Micrasterias Ralfs among desmids collected from several swamps, reservoirs, rivers and high land wetlands in South Korea from 2009 to 2013. In total 21 taxa of Micrasterias including three new species, Micrasterias spinosus sp. nov., M. jejuensis sp. nov. and M. koreanus sp. nov., were identified. In this study, photomicrographs of all of these are provided and briefly discussed with regard to their taxonomy, distribution and ecology within South Korea.

Clerodendrum ervatamioides (Lamiaceae): A new record to the flora of Vietnam

  • Heyjoong KIM;Do Van HAI;Tran Duc THIEN;Tran The BACH;Bui Hong QUANG;Duong Thi HOAN;Le Ngoc HAN;Tran Duc BINH;Ritesh Kumar CHOUDHARY;Joongku LEE
    • Korean Journal of Plant Taxonomy
    • /
    • v.52 no.4
    • /
    • pp.255-261
    • /
    • 2022
  • Clerodendrum ervatamioides C. Y. Wu was described in 1977 with its type locality in Yunnan, China. During our floristic investigation in the Muong Nhe Nature Reserve of Vietnam of Dien Bien province and in the Muong Te district of the Lai Chau province, we collected several specimens of Clerodendrum ervatamioides, marking the first record of its occurrence in Vietnam. In this paper, details of the morphological features, distribution, ecology, photo plates, and a table comparing the morphological features with its ally Clerodendrum garrettianum Craib are provided.

Characteristics of Naturalized Plants in the Wetland Protection Areas of Inland Wetlands (내륙습지 습지보호지역의 귀화식물 특성)

  • Cho, Kwang-Jin;Lim, Jeoncheol;Lee, Changsu;Yoon, Jungdo;Kim, Mijeong;Chu, Yeounsu
    • Ecology and Resilient Infrastructure
    • /
    • v.7 no.4
    • /
    • pp.374-387
    • /
    • 2020
  • This study was conducted to provide basic data for monitoring the trend of ecosystem change and establishing management plans for wetland protection areas by understanding the status of naturalized plants. In 21 wetland protection areas, 129 taxa, including 10 invasive alien species, were recorded. The naturalized plants appeared mostly as 71 taxa in the Chimsil wetland and were not observed in the Moojechineup and Sumeunmulbaengdui wetlands. Among the naturalized plants, 42 taxa (32.6%) originated from North America. Annual and biennial plants accounted for 68.2% (88 taxa). The frequencies of occurrence of naturalized plants growing in dry secondary grasses such as Erigeron annuus and Trifolium repens were high, and clonal plants that propagated by making stolons and struck roots accounted for 19.4% (25 taxa). The naturalized and urbanization indices showed positive correlations with location factors such as wetland, agricultural land, and used area. However, a negative correlation was found between altitude and forest. Therefore, a management plan that synthetically considers the occurrence frequency and growth characteristics of naturalized plants as well as the locational characteristics of wetland protection areas is required.

Occurrence and Distribution of C4 Plants under Diverse Agricultural Field Types in Korea (농업생태계에서 농경지유형에 따른 C4식물의 출현과 분포)

  • Cho, Kwang-Jin;Oh, Young-Ju;Kang, Kee-Kyung;Han, Min-Su;Na, Young-Eun;Kim, Miran;Choe, Lak-Jung;Kim, Myung-Hyun
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.15 no.2
    • /
    • pp.85-101
    • /
    • 2013
  • In order to search for distribution characteristics on C4 plants at the paddy fields, uplands, orchard and roadside in South Korea, vascular plants were investigated. Flora investigation had been carried out from May 2002 to October 2006 at 241 plots. In the results of survey, the flora of these areas consist of 74 families, 231 genera and 352 species totally. The class frequencies were arranged by the order of Magnoliopsidae (255 species), Monocotyledoneae (89 species), Pteropsida (7 species) and Sphenopsida (1 species). The number of species in each investigated agricultural field types was 55 families with 203 species in paddy field, 49 families with 218 species in uplands, 44 families with 115 species in orchard and 48 families with 202 species in roadside respectiviely. Representative species compositions of these four agricultural field types were characterized by Artemisia princeps, Persicaria thunbergii in paddy field, Artemisia princeps, Erigeron annuus in upland and roadside, Commelina communis, Digitaria ciliaris in orchard, respectively. Therefore, indicative species in agricultural ecosystem was Artemisia princeps. Among the investigated 352 species, $C_4$ plants identified were 38 species, and the occurrence ratio of $C_4$ monocotyledonous plants were higher in paddy field, orchard and roadside than upland. Such differences in the occurrence ratio of $C_4$ plants under diverse agricultural field types reflect differences in environmental condition such as micro-climate, soil moisture under various agricultural fields. Dominant $C_4$ monocotyledonous plants were Digitaria ciliaris and Commelina communis, while $C_4$ dicotyledonous plants were Amaranthus mangostanus and Chenopodium album var. centrorubrum in agricultural fields. Naturalized plants were identified as 47 species and occurrence ratio were higher in upland and roadside than other agricultural field types. Among the investigated naturalized plants, $C_4$ plants were Amaranthus mangostanus and Amaranthus retroflexus. Distribution characteristics of representative $C_4$ plants in agricultural field types, revealed that the projected increase in temperature due to climate change may provide better conditions for the growth of $C_4$ plants. Thus, the necessity of long-term monitoring should be conducted on the diffusion of $C_4$ plants that may threaten influence agroecosystem in Korea.

Occurrence of Modern Planktonic Foraminiferal Species and their Seasonal Variations around Jeju Island, Korea (제주근해에 출현하는 현생 부유성 유공충 종과 계절변화)

  • Hyun, Sangmin;Kimoto, Katsunori;Cho, Sung-Hwan
    • Ocean and Polar Research
    • /
    • v.35 no.2
    • /
    • pp.181-191
    • /
    • 2013
  • To investigate the occurrence of modern living planktonic foraminiferal species and their seasonal variations around Jeju Island, we conducted planktonic foraminiferal sampling at KIOST's regular sampling sites during 16 months. In total seven genus and 16 modern planktonic foraminiferal species were identified with six dominant species. Dominant species were Gloigerinoides sacculifer, Globigerinoides ruber, Globigerina bulloides, Noegloboquadrina dutertrei, Pulleniatina obliquiloculata, and Globorotalia inflata. Most of the species were characterized as being typical subtropical species and showed seasonal variations and/or intermittent occurrence from season to season. The occurrence of living foraminifera revealed a strong relationship with water temperature, but not with salinity. Species succession seems to occur along with water temperature changes. Some patch distribution and water temperature dependences appear to be significant since there is a high degree of variation in the occurrence patterns of species and standing stock. More detailed quantitative study is necessary to confirm the species diversity and seasonal variations of planktonic foraminifera and related ocean environmental changes.

Unraveling the Contributing Factors of Sarcopenia in Young Korean Male Adults: A Study of Occurrence, Somatometric, Biochemical, and Behavioral Characteristics

  • Jongseok Hwang
    • Journal of the Korean Society of Physical Medicine
    • /
    • v.18 no.3
    • /
    • pp.21-30
    • /
    • 2023
  • PURPOSE: The present study evaluated the occurrence, somatometric, biochemical, and behavioral characteristics of young Korean sarcopenic males aged between 30 to 39 years. METHODS: The study involved a total of 1,546 participants. These individuals were divided into two distinct groups based on their skeletal muscle mass index. Of these, 49 participants were categorized into the sarcopenia group, while the remaining 1,497 individuals were placed in the normal group. The researchers analyzed the occurrence of sarcopenia, somatometric, biochemical, and behavioral characteristics such as height, weight, body mass index (BMI), waist circumference (WC), skeletal muscle mass index, fasting glucose (FG), triglyceride and total cholesterol (TC) levels, systolic (SBP) and diastolic blood pressure (DBP), and the drinking and smoking status. A complex sampling data analysis was performed. RESULTS: The weighted occurrence of sarcopenia was found to be 3.24%, (95% confidence interval (CI) of 2.39% to 4.36%). The somatometric contributing factors were height, BMI, and WC (p < .05). Triglyceride and TC levels exhibited statistically significant differences in the biochemical variables (p < .05). The behavioral characteristics, including the drinking and smoking status, had no statistical significance (p > .05). CONCLUSION: This study identified specific occurrences of sarcopenia and contributing factors in young Korean men.