• 제목/요약/키워드: important species

검색결과 3,585건 처리시간 0.031초

유류오염지역의 미생물 분포 및 활성도에 관한 연구 (The Study of Microbial Population & Dynamics in Hydrocarbon Contaminated Areas)

  • 김무훈;김순기;이원권;경우성;박덕신
    • 한국지하수토양환경학회:학술대회논문집
    • /
    • 한국지하수토양환경학회 1999년도 추계학술발표회
    • /
    • pp.28-31
    • /
    • 1999
  • The purpose of this study is to see the effect of microbial population and dynamics of the indigeonous microorganisms on hydrocarbon contaminated areas. The microbial structures and activities to determine the microbial capabilities of the contaminated sites are very important for the remedial action technology selection. Throughout microbial studies on different conditions by ETS(Electron Transport System) and microbial activity analysis, it was found that aeration and water contents are the most important factors in this site remediation. According to test results, Burkholderia spp. was dominant species, and acclimation is also an important factor for the accerelated biodegradation.

  • PDF

Environmental Factors Influencing Tree Species Regeneration in Different Forest Stands Growing on a Limestone Hill in Phrae Province, Northern Thailand

  • Asanok, Lamthai;Marod, Dokrak
    • Journal of Forest and Environmental Science
    • /
    • 제32권3호
    • /
    • pp.237-252
    • /
    • 2016
  • Improved knowledge of the environmental factors affecting the natural regeneration of tree species in limestone forest is urgently required for species conservation. We examined the environmental factors and tree species characteristics that are important for colonization in diverse forest stands growing on a limestone hill in northern Thailand. Our analysis estimated the relative influence of forest structure and environmental factors on the regeneration traits of tree species. We established sixty-four $100-m^2$ plots in four forest stands on the limestone hill. We determined the species composition of canopy trees, regenerating seedlings, and saplings in relation to the physical environment. The relationships between environmental variables and tree species abundance were assessed by canonical correspondence analysis (CCA), and we used generalized linear mixed models to examine data on seedling/sapling abundances. The CCA ordination indicated that the abundance of tree species within the mixed deciduous forest was closely related to soil depth. The abundances of tree species growing within the sink-hole and hill-slope stands were positively related to the extent of rocky outcropping; light and soil moisture positively influenced the abundance of tree species in the hill-cliff stand. Physical factors had a greater effect on tree regeneration than did factors related to forest structure. Tree species, such as Ficus macleilandii, Dracaena cochinchinensis, and Phyllanthus mirabilis within the hill-cliff or sink-hole stand, colonized well on large rocky outcroppings that were well illuminated and had soft soils. These species regenerated well under conditions prevailing on the limestone hill. The colonization of several species in other stands was negatively influenced by environmental conditions at these sites. We found that natural regeneration of tree species on the limestone hill was difficult because of the prevailing combination of physical and biological factors. The influence of these factors was species dependent, and the magnitude of effects varied across forest stands.

Comparative Pathogenicity and Host Ranges of Magnaporthe oryzae and Related Species

  • Chung, Hyunjung;Goh, Jaeduk;Han, Seong-Sook;Roh, Jae-Hwan;Kim, Yangseon;Heu, Sunggi;Shim, Hyeong-Kwon;Jeong, Da Gyeong;Kang, In Jeong;Yang, Jung-Wook
    • The Plant Pathology Journal
    • /
    • 제36권4호
    • /
    • pp.305-313
    • /
    • 2020
  • Host shifting and host expansion of fungal plant pathogens increases the rate of emergence of new pathogens and the incidence of disease in various crops, which threaten global food security. Magnaporthe species cause serious disease in rice, namely rice blast disease, as well as in many alternative hosts, including wheat, barley, and millet. A severe outbreak of wheat blast due to Magnaporthe oryzae occurred recently in Bangladesh, after the fungus was introduced from South America, causing great loss of yield. This outbreak of wheat blast is of growing concern, because it might spread to adjacent wheat-producing areas. Therefore, it is important to understand the host range and population structure of M. oryzae and related species for determining the evolutionary relationships among Magnaporthe species and for managing blast disease in the field. Here, we collected isolates of M. oryzae and related species from various Poaceae species, including crops and weeds surrounding rice fields, in Korea and determined their phylogenetic relationships and host species specificity. Internal transcribed spacer-mediated phylogenetic analysis revealed that M. oryzae and related species are classified into four groups primarily including isolates from rice, crabgrass, millet and tall fescue. Based on pathogenicity assays, M. oryzae and related species can infect different Poaceae hosts and move among hosts, suggesting the potential for host shifting and host expansion in nature. These results provide important information on the diversification of M. oryzae and related species with a broad range of Poaceae as hosts in crop fields.

어류서식처 평가 및 목표종 도입을 통한 하천복원방향 - 부안댐 상류 거석천과 청림습지를 대상으로 - (Stream Restoration Guidelines by Evaluation of Fish Habitat and Introducing of the Keystone Species - Geo-seok Stream and Cheonglim Wetland in Upper Stream of Buan-Dam -)

  • 박선아;이명우
    • 한국환경복원기술학회지
    • /
    • 제11권4호
    • /
    • pp.24-36
    • /
    • 2008
  • The essence of a natural stream restoration project is providing habitats for various creatures in terms of the stream's environmental function. This research suggests the problems of natural stream restoration project by studying streams in terms of habitats for creatures and reviewing the national and international cases on existing natural stream restoration project. As a solution for the above, this research suggests a preservation method for biotope of upper stream areas focusing on the fish biotope area considering the ecological characteristics and preservation value of the respective stream so that the stream can be preserved as habitats for creatures. The research was carried out on Cheonglimli Baekcheon region which is an upper stream area of Buan-Dam located in the public park in Byunsanbando, Buangoon, Jeonlabookdo. We suggest the preservation method based on the habitat environment and keystone species of fish. The habitat environment evaluation was carried out mainly being divided into three groups namely, habitats and surrounding environment, reservoir's features and fish way and the diversity of fish. By improving the problematic elements discovered through such evaluation, it tries to improve the biotope of the stream and continuously preserve the stream. In addition, in order to restore the stream as habitats for various creatures, this research suggests to select keystone species which are suitable for the stream environment and restore the habitats based on the keystone species rather than restoring habitats for all species. Fish not only plays the role of a consumer of Epilithic algae and water beetles but also plays an important ecological role as a food for birds or small mammalia. If such ecologically important biotope for fish is preserved, the ecological environment of the stream will be maintained more stably.

Detecting response patterns of zooplankton to environmental parameters in shallow freshwater wetlands: discovery of the role of macrophytes as microhabitat for epiphytic zooplankton

  • Choi, Jong-Yun;Kim, Seong-Ki;Jeng, Kwang-Seuk;Joo, Gea-Jae
    • Journal of Ecology and Environment
    • /
    • 제38권2호
    • /
    • pp.133-143
    • /
    • 2015
  • Freshwater macrophytes improve the structural heterogeneity of microhabitats in water, often providing an important habitat for zooplankton. Some studies have focused on the overall influence of macrophytes on zooplankton, but the effects of macrophyte in relation to different habitat characteristics of zooplankton (e.g., epiphytic and pelagic) have not been intensively studied. We hypothesized that different habitat structures (i.e., macrophyte habitat) would strongly affect zooplankton distribution. We investigated zooplankton density and diversity, macrophyte characteristics (dry weight and species number), and environmental parameters in 40 shallow wetlands in South Korea. Patterns in the data were analyzed using a self-organizing map (SOM), which extracts information through competitive and adaptive properties. A total of 20 variables (11 environmental parameters and 9 zooplankton groups) were patterned onto the SOM. Based on a U-matrix, 3 clusters were identified from the model. Zooplankton assemblages were positively related to macrophyte characteristics (i.e., dry weight and species number). In particular, epiphytic species (i.e., epiphytic rotifers and cladocerans) exhibited a clear relationship with macrophyte characteristics, while large biomass and greater numbers of macrophyte species supported high zooplankton assemblages. Consequently, habitat heterogeneity in the macrophyte bed was recognized as an important factor to determine zooplankton distribution, particularly in epiphytic species. The results indicate that macrophytes are critical for heterogeneity in lentic freshwater ecosystems, and the inclusion of diverse plant species in wetland construction or restoration schemes is expected to generate ecologically healthy food webs.

Cervus elaphus 종의 sequencing과 BLAST search에 의한 감별 (Identification of Cervus elaphus Species by Sequencing Analysis and BLAST Search)

  • 서정철;김민정;이찬;임강현
    • 대한본초학회지
    • /
    • 제21권2호
    • /
    • pp.129-133
    • /
    • 2006
  • Objectives : Cervus elaphus species are some of the most medicinally important genera in the Oriental medicine. This study was performed to determine if Cenvus elaphus species could be identified by sequencing analysis and to verify Basic Local Alignment Search Tool (BLAST) search, which was used to assess genetic identification. Methods : The DNAs of Cervus elaphus species were extracted, amplified by PCR, and sequenced. The DNAs of Cervus species were identified by BLAST search in website. Results : By BLAST search one of Cervus elaphus species was identified as Cervus elaphussibericus but the other was identified as Cervus elaphus nelsoni. This work showed that identification can efficiently be performed by BLAST search. Conclusion : These results suggest that sequencing following BLAST search might be able to provide the identification of Cervus elaphus species.

  • PDF

Species richness related to landscape characteristics of uninhabited islands in Korea

  • Rho, Paikho
    • Journal of Ecology and Environment
    • /
    • 제33권2호
    • /
    • pp.105-114
    • /
    • 2010
  • The principal objective of this study was to characterize the relationships between geographical conditions (e.g., island area, distance to mainland) and landscape structures of uninhabited islands, and to evaluate the effects of islands and their landscape structures on species richness. One hundred randomly selected islands and 5,000 m buffered areas derived from the boundaries of each island were used to summarize the number of observed bird species, and landscape pattern indices, particularly patch density, edge density, shape index, and mean nearest neighboring distance. Spatial arrangements of individual patch type at the class level, which are markedly affected by the distance from an island to the mainland, have a superior ability to explain the variances in species richness, as compared to the geographical conditions and landscape pattern indices at the landscape level. The results demonstrate that the patch type landscape structure is the primary factor affecting species richness, as well as the distance to the mainland. In particular, landscape pattern indices of cropland/pasture and woody cover are statistically significant in terms of explaining species richness, which suggests that food resources and appropriate conditions in landscape structures of habitat types are assumed as important elements in attracting bird species. This study also proposes the importance of evaluation on the landscape structure of each island, in order to designate protected areas and to establish a management plan for species conservation in uninhabited islands.

선택 속성에 따른 생선회 시장의 포지셔닝에 관한 연구 (A Study on the Positioning of Sliced Raw Fish Market by Selection Attributes)

  • 임소희;김지웅;장영수
    • 수산경영론집
    • /
    • 제48권2호
    • /
    • pp.53-66
    • /
    • 2017
  • More than 90% of cultured fish is consumed by sliced raw fish which is usually an eating out menu in South Korea. In order to develop the aquaculture industry in Korea, It is very important to know whether consumers can differentiate each species or not and how consumers recognize each species by certain criteria. for example taste, seasonal preference. The purpose of this study is to understand the competitive relationship through positioning studies of each species by the selection attributes. A total of 221 consumers were surveyed in korea. This study adapted multidimensional scaling(MDS) analysis to explore how consumers position sliced raw fish species based on selection attributes. This study has produced perceptual maps of sliced raw fish market. Empirical data was collected from sliced raw fish consumers in Korea. The results of MDS analysis reveal that 7 species are divided into 3 groups(flat fish, black rock fish), (red sea bream, salmon, tuna), (sea bass, gray mullet). In this study flat fish and black rock fish are perceived as safe, familiar, good value species. Red seabream, salmon, tuna are perceived as luxurious species. Sea bass and gray mullet are perceived as unfamiliar species.

생태통로 식재수종의 현황 및 문제점 고찰 (The Existing Conditions and Problems of Ecological Corridor in Korea - Focusing on Planting Species -)

  • 김명수
    • 한국환경복원기술학회지
    • /
    • 제8권1호
    • /
    • pp.17-26
    • /
    • 2005
  • Ecological corridor is the facility to connect two habitats fragmented by roads, dam, housing and industrial area. Critics of faunal corridors have suggested that they are simply an untested application of unproved island biogeography theory. But, everyone agree that ecological corridor is important useful structural components that help animal movement in fragmented landscapes. There are 52 ecological corridors in Korea. We investigated 43 ecological corridors of these and recorded the size of corridor, planting species, management and growth condition. We compared planting species to nearby exiting vegetation species and structure. We found that there are no considerations for many aspects of planting, for example, planting species, structure, animal migration and behavior, surrounding vegetation etc. Expecially, It was ignored management of plants, difference of surrounding vegetation, lacks of diverse planting species and structure. We suggest planting the native species of tall tree, shrub and ground cover, edge planting for transitional space between road and natural habitat, planting for foraging and breeding of target animal, diverse layer vegetation, and open space of center for rapid animal dispersal.

Analysis of Prey of Mandarin Fish and Large Mouth Bass and Distribution of Fish Population in Lake Paro, Korea

  • Lee, Jaeyong;Lee, Kwang Yeol;Park, Sungchul;Choi, Jaeseok;Jang, Hong Gi;Kim, Joon Chul
    • 한국환경생태학회지
    • /
    • 제29권2호
    • /
    • pp.210-220
    • /
    • 2015
  • We quantified temporal and spatial changes in the habitat for fish populations, the distribution of mandarin fish(Siniperca scherzeri) and an introduced species, largemouth bass(Micropterus salmoides) in Lake Paro and inflowing streams. The number of fish species identified in Lake Paro and the tributary streams included 10 families, 24 species and 10 families 30 species, respectively. The dominant fish species in Lake Paro were Zacco platypus, Hemibarbus labeo, Squalidus gracilis majimae, S. scherzeri and Tridentiger brevispinis, Z. platypus, Z. koreanus, and S. gracilis majimae in the inflowing streams. Although the habitat segregation for S. scherzeri and M. salmoides occurs, these two species showed the use of the fishes of the family Gobiidae as an important prey item based on IRI analysis. S. scherzeri and M. salmoides preyed mainly on T. brevispinis(67.4 %) and R. brunneus(84.0 %), respectively. The species preyed on by S. scherzeri and M. salmoides were benthic fishes that inhabit shallow water depths around the lake and have little swimming ability.