• Title/Summary/Keyword: Annual plants

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Annual Flesh Weight Yield of Oversowing Grassland and Vegetation Succession of Abandoned Grassland in Wonju area (원주지역 산지초지의 연간 생초수량과 버려진 초지의 식생천이에 관한 연구)

  • 이성규
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.17 no.3
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    • pp.257-264
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    • 1997
  • This study was conducted to assess present situiatioq of oversowing grassland yield and vegetational succession of abondoned since 6 years passed grassland in Wonju. The highest annual h s h weight yield was 28ton/ ha and the lowest was I lton/ha and the grass rate of investigated oversowing grasslands were range from 19.5% to 9lS%. The soil properties of abandoned oversowing grassland, such as soil pH content of organic matter, available phosphorus, exchangeable potasium, calcium, and magnesium were 5.7, 3.88%, 3lppm, O.lme1100g 4.9meI 100g and 2.3me/100g, respectively. The floristic composition of abandoned grassland were composed 26 species of vascular plants. The dominant species based on SDR, of grassland were Miscanthus sinensis var. purpurascens(56.32%). Artemisia feddei(48.62%) and Dactylis glomerata(43.85%). The biological spectra showed the H-$D_1$-$R_5$-e type.

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A Study on Annual Atmospheric Dispersion Factors Between Continuous and Purge Releases of Gaseous Radioactive Effluents

  • Kim, Na-Hyun;Hwang, Won-Tae;Kim, Chang-Lak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.19 no.2
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    • pp.177-186
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    • 2021
  • Radioactive materials from nuclear power facilities can be released into the atmosphere through various channels. Recently, the dispersion of radioactive materials has become critical issue in Korea after Kori Unit 1 and Wolsong Unit 1 were permanently shut down. In this study, annual atmospheric dispersion factors were compared based on the continuous release and purge release using the XOQDOQ computer program, a method for calculating atmospheric dispersion factors at commercial nuclear power stations. The meteorological data analyzed in this study was based on the Shin Kori nuclear power meteorological tower which has the largest operating nuclear power plants in Korea, for three years (from 2008 to 2010). The analysis results of the dispersion factor of the radioactive material release obtained using the XOQDOQ program showed that the difference between the continuous release and purge release was within two times. This study will be valuable helpful for revealing the uncertainty of the predictive atmospheric dispersion factor to achieve regulation.

A Study on Eco-efficiency in power plants using DEA Analysis (DEA 모형을 이용한 발전회사 환경효율성에 대한 연구)

  • Han, Jung-Hee
    • Journal of Digital Convergence
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    • v.11 no.5
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    • pp.119-133
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    • 2013
  • This study aims to provide power generating plants with eco-efficiency information. To implement the purposes, of study, both DEA(Data, Envelopment Analysis) model and interview were incorporated in terms of methodologies. To analyze the managerial efficiency, total labor cost and number of employees were considered as input factors. CO2, NOx, and water also were considered as input factors to analyze eco-efficiency. Both annual total power product and annual total revenue were used as output factors. CRS(Constant Return to Scale) and VRS(Variable Return to) model were facilitated in this analysis. According to the findings, most of the power plants were evaluated as 'Efficient'' taking into consideration of average value, both 0.928 from CCR model and 0.969 from VRS model. 7 DMUs including DMU3 and DMU12 are efficient out of 35 DMUs relatively, other DMUs are inefficient. For results of inefficient output factors distribution, it was found that inefficiency for NOx was marked relatively higher than CO2. In order to improve the eco-efficiency in the power plants in the long term, the target amount of Co2 as well as NOx reduction needs to be properly proposed in consideration of particularity of power plants. In the long run, renewable energy, alternative fuels should be adapted to reduce the eco-inefficient.

The Characteristics of Vegetative Composition Among Plants in the Heronries (백로류 집단번식지의 식물사회 특성)

  • Ahn, Kyunghwan;Lim, Jeongcheol;Han, Changuk;Lee, Yunkoung;Cho, Hangsoo;Suh, Jaehwa;Suh, Minhwan;Shin, Youngkyu;Kim, Myungjin
    • Journal of Environmental Impact Assessment
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    • v.24 no.5
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    • pp.499-515
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    • 2015
  • The purpose of this study was to understand phytosociological characteristics and changes, providing basic ecology informations based for heronries. We investigated the 25 heronries sites to have more than a hundred nests in the country. The vegetations of heronries were arranged 8 plant communities that consisted of 60 families, 129 genuses and 167 species including 17 species of exotic species. The communities of heronries were composed of high NCD (Net Contribution Degree) of plants, such as pokeberry (Phytolacca americana), japanese chaff flower (Achyranthes japonica), asiatic dayflower (Commelina communis) including diagnosis species, that was heliophilous and tolerance of eutrophic and/or acidic soil condition, and had the highest composition with the annual plants. As locational condition, they were distributed a favorite feeding place (rice field, stream etc.) inside 0.5 km radius, and located on the eastern slope of the mountain. The vegetative composition among plants in the heronries didn't have plant sociological characteristics for environmental conditions of the sites. But generally, they had trends in floristic composition like the areas of polluted soil, open canopy and disturbance.

Growth environment characteristics of the habitat of Epilobium hirsutum L., a class II endangered wildlife species

  • Kwang Jin Cho;Hyeong Cheol Lee;Sang Uk Han;Hae Seon Shin;Pyoung Beom Kim
    • Journal of Ecology and Environment
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    • v.47 no.4
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    • pp.282-289
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    • 2023
  • Background: As wildlife habitats are being destroyed and growth environments are changing, the survival of animals and plants is under threat. Epilobium hirsutum L., a species that inhabits wetlands, has held legally protected status since 2012. However, no specific measures are currently in place to protect its habitat, leading to a decline in remaining populations as a result of land use change and human activities. Results: The growth environment (including location, climate, land use, soil, and vegetation) of the five habitat sites (Samcheok, Taebaek1, Taebaek2, Cheongsong, Ulleung) of E. hirsutum L. was investigated and analyzed. These habitats were predominantly situated in flat areas with gentle south-facing slopes, at an average altitude of 452.7 m (8-726 m) above sea level in Gangwon-do and Gyeongsangbuk-do. The average annual temperature ranged 11.5℃ (9.2℃-12.9℃), whereas the average annual precipitation ranged 1,304.5 mm (1,062.7-1,590.7 mm). The surrounding land use status was mainly characterized by mountainous areas, and human interference, such as agricultural land and roads, was commonly found in proximity to these natural habitats. Soil physicochemical analysis revealed that the soil was predominantly sandy loam with a slightly high sand content. The average pH measured 7.64, indicating an alkaline environment, and electrical conductivity (EC) averaged 0.33 dS/m. Organic matter (OM) content averaged 66.44 g/kg, available phosphoric acid (P2O5) content averaged 115.73 mg/kg, and cation exchange capacity (CEC) averaged 23.43 cmolc/kg. The exchangeable cations ranged 0.09-0.43 cmol+/kg for potassium (K), 10.23-16.21 cmol+/kg for calcium (Ca), 0.67-4.94 cmol+/kg for magnesium (Mg), and 0.05-0.74 cmol+/kg for sodium (Na). The vegetation type was categorized as E. hirsutum community with high numbers of E. hirsutum L., Persicaria thunbergii (Siebold & Zucc.) H. Gross, Phragmites japonica Steud., Humulus japonicus (Siebold & Zucc.), and Bidens frondosa L.. An ecological flora analysis, including the proportion of lianas, naturalized plants, and annual herbaceous plants, revealed that the native habitat of E. hirsutum L. was ecologically unstable. Conclusions: Analysis of the habitat of E. hirsutum L., a class II endangered wildlife species, provided essential data for local conservation and restoration efforts.

Impact on Introduction of the Alien Plants by Road Development Projects (도로개발 사업이 외래식물 유입에 미치는 영향)

  • Chu, Yunsoo;Kim, Jung-Kwon;Lee, Hyohyemi
    • Ecology and Resilient Infrastructure
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    • v.4 no.3
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    • pp.156-168
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    • 2017
  • Linear development such as road and railway construction is considered to be an important factor in the dipersion agent of alien species. The purpose of this study is to investigate the effect of road project implementation on the introduction of alien plants. We selected the roadworks that have been completed or completed by more than 70% of the projects in the Han River basin environment agency. The alien plant data were divided into five phases: pre-construction (P0) and construction (P25, P50, P75, P100) according to the annual process rate. As the construction progresses, the naturalization rate, the urbanization index and the tendency of the number of exotic plants increase. Especially, alien plants were introduced rapidly at the beginning of the construction period, and the introduced species continued to appear until the construction was completed. Therefore, it is necessary to minimize the introduction of ailen plants by concentrating management of embankment process and the vegetation restoration process at the beginning of roadworks.

The optimal balance between sexual and asexual reproduction in variable environments: a systematic review

  • Yang, Yun Young;Kim, Jae Geun
    • Journal of Ecology and Environment
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    • v.40 no.2
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    • pp.89-106
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    • 2016
  • Many plant species have two modes of reproduction: sexual and asexual. Both modes of reproduction have often been viewed as adaptations to temporally or spatially variable environments. The plant should adjust partitioning to match changes in the estimated success of the two reproductive modes. Perennial plants showed that favorable habitats in soil nutrients or water content tend to promote clonal growth over sexual reproduction. In contrast, under high light-quantity conditions, clonal plants tend to allocate more biomass to sexual reproduction and less to clonal propagation. On the other hand, plants with chasmogamous and cleistogamous flowers provides with a greater tendency of the opportunity to ensure some seed set in any stressful environmental conditions such as low light, low soil nutrients, or low soil moisture. It is considered that vegetative reproduction has high competitive ability and is the major means to expand established population of perennial plants, whereas cleistogamous reproduction is insurance to persist in stressful sites due to being strong. Chasmogamous reproduction mainly enhances established and new population. Therefore, the functions of sexual and asexual propagules of perennial or annual plants differ from each other. These traits of propagule thus determine its success at a particular region of any environmental gradients. Eventually, if environmental resources or stress levels change in either space or time, species composition will probably also change. The reason based on which the plants differ with respect to favored reproduction modes in each environmental condition, may be involved in their specific realized niche.

Industrial Development of Medicinal Plants in China (중국에 있어서 약용식물의 산업적 발달)

  • Gao, Wen-Yuan;Paek, Kee-Yoeup;Peng, Yong;Xiao, Pei-Gen
    • Korean Journal of Medicinal Crop Science
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    • v.7 no.4
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    • pp.316-324
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    • 1999
  • In China, medicinal plants play almost the same important role in the general health service as the western medicine. In this paper, we present a brief review about the industrial development of medicinal plants in China. A nation-wide survey shows that there are 11, 118 species of medicinal plants in China. The total annual output value of natural products is about $6, 000. The output value of preparations is 3 billion US dollars. Over 100 new drugs have been developed from the medicinal plants. As the trend worldwide today that human-being favors the way of life back to nature, medicinal plants will play a very important role, and their industrial exploitation will certainly be keeping a key position for human health.

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Change of Actual Vegetation and Herbaceous Vegetation Structure of Haneul Park District, in World Cup Park, Seoul (월드컵공원 하늘공원지구 현존식생 및 초본식생구조 변화연구)

  • Han, Bong-Ho;Kim, Ji-Seok;Bae, Jeong-Hee;Lee, Kyong-Jae
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.1
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    • pp.38-48
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    • 2008
  • This study examines the characteristics of the herbaceous vegetation structure of Haneul Park District in World Cup Park, which had previously been used as a landfill for 15 years. The survey was carried out through actual vegetation and vegetation structures from 2003 to 2006, biannually. Firstly, as a result of analysis of actual vegetation, the autumn season changed more quickly over the 2 year span than did the spring season in terms of actual vegetation area. Annual plants increased for the initial $3{\sim}4$ years and then perennial plants increased. Secondly, the results of analysis in vegetation structure are as follows: 1. The number of planted species gradually decreased. 2. Miscanthus sinensis var. purpurascens of the control region was maintained but Imperata cylindrica var. koenigii of the non-control region was invaded by Miscanthus sacchariflorus, Glycine soja and Phragmites communis etc. 3. Planted species in the control region were maintained in superior state, but the non-control region was changed by natural occurrence plants until 2006, the fourth year. 4. Physostegia virginiana and Aster koraiensis which were planted in the non-control region were maintained but most of planted species weakened and changed by natural occurrence plants including Erigeron annuus, Artemisia princeps, Setaria faberii and Phragmites communis etc. Based on the results, we suggested the management method of herbaceous vegetation in the Haneul Park District.

Characteristic studies of coal power plants ash sample and monitoring of PM 2.5

  • Thriveni., T;Ramakrishna., CH;Nam, Seong Young;kim, Chunsik;Ahn, Ji Whan
    • Journal of Energy Engineering
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    • v.26 no.4
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    • pp.45-56
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    • 2017
  • Coal power plants produce electricity for the nation's power grid, but they also produce more hazardous air emissions than any other industrial pollution sources. The quantity is staggering, over 386,000 tons of 84 separate hazardous air pollutants spew from over 400 plants in 46 states. In South Korea also, annual coal ash generation from coal-fired power plants were about 6 million tons in 2015. Pollutants containing particulate matter 10, 2.5 (PM10, PM2.5), heavy metals and dioxins from coal-fired power plant. The emissions threaten the health of people who live near these power plants, as well as those who live hundreds of miles away. These pollutants that have long-term impacts on the environment because they accumulate in soil, water and animals. The present study is to investigate the physical and chemical characteristics of coal-fired power plant fly ash and bottom ash contains particulate matter, whose particulate sizes are lower than $PM_{10}$ and $PM_{2.5}$ and heavy metals. There are wide commercial technologies were available for monitoring the PM 2.5 and ultra-fine particles, among those carbonation technology is a good tool for stabilizing the alkaline waste materials. We collected the coal ash samples from different coal power plants and the chemical composition of coal fly ash was characterized by XRF. In the present laboratory research approach reveals that potential application of carbonation technology for particulate matter $PM_{10}$, $PM_{2.5}$ and stabilization of heavy metals. The significance of this emerging carbonation technology was improving the chemical and physical properties of fly ash and bottom ash samples can facilitate wide re use in construction applications.