• Title/Summary/Keyword: Annual plants

Search Result 410, Processing Time 0.02 seconds

Performance Analyzing Technique of Small Hydro Power (소수력발전 성능특성 분석기법 연구)

  • Park, W.S.;Lee, C.H.
    • Journal of the Korean Solar Energy Society
    • /
    • v.21 no.1
    • /
    • pp.21-25
    • /
    • 2001
  • A methodology to predict the output performance of small hydro power using discharge of sewage treatment plant has been studied. Two sewage treatment plants existing in Chunrabuk-Do were selected and the output performance characteristics for these plants were analyzed, using developed model. As a result, it was found that the developed model in this study can be used to analyze the output characteristics for small hydro power using discharge of sewage treatment plant. Additionally, primary design specifications such as design flowrate, capacity, operational rate and annual electricity production were estimated and discussed for two plants.

  • PDF

Hydrophytes Flora of Seven Swamp Inland in Korea (우리나라 7개 내륙습지의 수생식물 분포상)

  • Kim, Yoo Sun
    • FLOWER RESEARCH JOURNAL
    • /
    • v.17 no.1
    • /
    • pp.52-61
    • /
    • 2009
  • This study was conducted, to understand floras and circumstances of Korean swamp inland. The floras of 7 swamp inland were 32 families, 49 genus and 69 species. They are accounted for 23% with 16 species of Cyteraceae, one group of annual herbaceous plants, and 6 groups of perennial herbaceous plants (Scirpus tabernaemontani, Phramites communis, Zizania latifolia, Persicaria thunvergiicsiebold, Typha latifolia, Juncus krameri, and Juncus effusus). The plants of Scirpus tabernaemontani, Phramites communis, Zizania latifolia, Persicaria thunvergiicsiebold, Typha latifolia, Juncus krameri, and Potagometon distinctus turnes out a dominant species.

Role of NTFPs in Rural Livelihood of Lao PDR

  • Xayvongsa, Lamphoune;Bae, Young-Soo;Choi, Yong-Eui;Yi, Jae-Seon
    • Journal of Forest and Environmental Science
    • /
    • v.25 no.2
    • /
    • pp.85-91
    • /
    • 2009
  • About 83% of the total population of Lao PDR lives in rural areas. People living near forest are highly dependent on the forest resources closed to their villages. Especially non-timber forest products (NTFPs) provide a wide range of subsistence needs and are the main source of their cash income. They also make a significant contribution to the country economy. The annual export value of NTFPs is considerably high. 708 edible NTFP species (238 edible plants and 470 animals) have been recorded so far, and about 400 plants have been reported and used as medicinal plants by Lao people. One hundred NTFP species are considered as commercial forest products. The striking trend in NTFP resources is the decline of some commercial species due to increased demand on them for commercialization, and the loss of forest by rapid population growth. To sustainablely manage the NTFPs resources, a number of new management systems are under development and support in progress by the government.

  • PDF

Seed Germination of Surface Soil for Restoration of Disturbance Place - Bare Land and abandoned Field, Yesan-gun, Korea - (교란지 복구를 위한 표토의 매토종자 발아특성 - 예산군의 나지와 묵밭 토양-)

  • Kang, Hee-Kyoung;Cho, Nam-Kyoung;Song, Hong-Seon
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.20 no.6
    • /
    • pp.79-92
    • /
    • 2017
  • To offer the basic data of vegetation restoration by buried seed of soil, this research was conducted at bare land and abandoned field in Yesan-gun. Germination plants of buried seed were consisted of 40 taxa (37 species, 3 varieties) in bare land, and 41 taxa (37 species, 4 varieties) in abandoned field. Classification of germination plants by family was the most in Gramineae, and emergent frequency of plots was the highest of Digitaria ciliaris. The soil depth of the most plants appearance was 2~5cm in bare land and 5~10cm in abandoned field, and the soil depth of the most population appearance was 0~2cm both in bare land and in abandoned field. Population number of buried seed germination was decreased according to soil depth. Crepidiastrum sonchifolium was a plant that population number of buried seed germination is the most. Similarity index was 0.33 in aerial part plants and buried seed plants, and 0.55 in bare land and abandoned field.

Effects of cutting and sowing seeds of native species on giant ragweed invasion and plant diversity in a field experiment

  • Byun, Chaeho;Choi, Ho;Kang, Hojeong
    • Journal of Ecology and Environment
    • /
    • v.44 no.4
    • /
    • pp.256-263
    • /
    • 2020
  • Background: Ambrosia trifida is a highly invasive annual plant, but effective control methods have not been proposed. Among various eradication methods, cutting is a simple measure to control invasive plants, and sowing seeds of native plants may effectively increase biotic resistance to invasion. In this study, we conducted a field experiment with two treatments: cutting and sowing seeds of six native or naturalized plants. Results: We found a significantly lower A. trifida abundance after cutting than in the control (77% decrease). Sowing seeds of native species did not provide any additional benefit for the control of A. trifida, but increased the importance values and diversity of other native vegetation. The abundance of A. trifida was negatively correlated with that of other plant taxa based on plant cover, biomass, and density. However, biotic resistance of sown plants was not effective to control invasion because A. trifida was so competitive. Conclusions: We concluded that cutting is an effective measure to control Ambrosia trifida while sowing seeds of native plants can increase native plant diversity.

Characteristics of Naturalized Plants in the Gwangyang Steel Works (광양제철소 내의 귀화식물상의 특성)

  • Oh, Hyun-Kyung;Kim, Dal-Ho;Kim, Do-Gyun;Nam, Woong
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.12 no.3
    • /
    • pp.9-20
    • /
    • 2009
  • The naturalized plants in the Gwangyang Steel Works were listed 70 taxa; 18 families, 51 genus, 66 species, 3 varieties and 1 form. by field survey. The naturalized plants divided into pattern by survey of annual plants ratio is 31 taxa (44.3%) by life form spectrum and perennials is 23 taxa (32.9%), biennials is 13 taxa (18.5%), two trees (Robinia pseudoacacia, Alianthus altissima) and one shrub (Amorpha furticosa) were founded. According to analysis results form place of origin, Europe covered 26 taxa (37.1%), North America covered 23 taxa (32.8%). Naturalized degree 3 plants, as common but not abundant, founded as 24 taxa (35.0%) were hold most highly ratio, naturalized degree 1 plants founded as 3 taxa (4.0%) were hold lowest. Introduction period 1 covered 31 taxa (44.3%) have had highest score and period 2 covered 11 taxa (15.7%) have had lowest scores. In addition, the urbanization index based on 271 taxa was 25.8% and 2 taxa (Solanum carolinense, Ambrosia artemisiaefolia) is growing in the Gwangyang Steel Works by ecosystem disturbing wild plants. Meanwhile, Ambrosia artemisiaefolia have confirmed into several tens~hundred in the Gwangyang Steel Works were damage the human body of plants develop an allergy to pollen. Solanium carolinense have composed several large communities about $10m{\times}10m$ ($100m^2$) and hold a dominant position, so management plan of the sequel of monitoring them might be required.

A Study on the Distribution Characteristics of Invasive Alien Plants in Ulsan City, South Korea (울산광역시 침입외래식물의 분포 현황과 특성에 관한 연구)

  • Lee, Yunkeun;Moon, Kyoung-hi;Lim, Ha-woo;Choi, Kee-ryong
    • Korean Journal of Ecology and Environment
    • /
    • v.52 no.2
    • /
    • pp.161-170
    • /
    • 2019
  • Invasive alien plants were identified and recorded in Ulsan city based on field surveys and related literatures. These plants consisted of 147 taxa in total, belonging to 30 families, 93 genera, 144 species, 2 subspecies and 1 variant. The family of Asteraceae was predominant with 42 taxa, followed by Gramineae with 27 taxa and Leguminosae with 15 taxa. According to the result of life-form based distribution analysis revealed that 62 taxa (42.2%) were annual plants, 48 taxa (33.6%) were perennial plants, 34 taxa (23.1%) were biennial plants, and 3 taxa (2%) were woody perennials. Compare to other administrative districts in Korea, prevalence of invasive alien plants in a certain city of Ulsan showed the seventh highest species number followed after Jeju, Gyeonggi, Jeonnam, Incheon, Seoul and Gangwon. On the basis of the results from the country origin analysis, two dominating taxa were introduced from Europe and America, 55 taxa and 51 taxa respectively. The spreading grade of alien plants was elucidated in order of 1 grade (PS) 67 grade (21.1%)>2 grade (MS) 31 taxa (21.1%)>5 grade (WS) 18 taxa (11.6%)>3 grade (CS) 17 taxa (11.6%)>4 grade (SS) 14 taxa (9.5%). Ulsan city is one of a pivotal conduit for the introduction of invasive alien plants. Thereby, reliable management plans are required to monitor these species.

Occurrence of Streamside Flora in relation to Environmental Condition at Ansungchon Creek (안성천 하천변 식물상 구성과 환경 조건과의 관계)

  • 안영희;송종석
    • Journal of Environmental Science International
    • /
    • v.12 no.6
    • /
    • pp.573-582
    • /
    • 2003
  • According to the survey map, the altitudes of up and down the Ansungchon were 242m and 49m accordingly. The width of the river was 4m at upperstream and became wider, lam at midstream and 114m at downstream. Water pH of the Ansungchon was measured variously in the range of 6.0-7.9 according to the surveyed times and areas. The water pH measured during June through August decreased continually and suddenly increased at the end of October. Phragmites iaponica, a major species of the fresh water emergent anchored hydrophytes, was surveyed mostly in the area of upperstream, Phragmites communis, Miscanthus sacchariflorus and Typha orientalis were surveyed in the areas of midstream and downstream, and Zizania latifolia was found in all areas of the river. The total of 101 taxa dividing into 32 families, 71 genera, 88 species, and 13 varieties have been inhabited in these areas. Among the inhabited plants, Poaceae was 21.8%, which appeared in the highest percent. Compositae was 20.8%, and Polygonaceae was 11.9%. In the surveyed areas, herbaceous plants were 95.1% and mostly occupied, and woody plants were 4.9%. Among the herbaceous plants, perennial plants were 52.5%, and annual and biannual plants were 28.7% and 13.9% accordingly. Naturalized plants dividing into 8 families and 18 genera have been found in the surveyed areas. The number of the naturalized plants increased from upperstream to downstream as the environmental disruption became worse. Only 2.5% of the total naturalized plants were appeared in up, 17.7% in midstream, and 28.6% in downstream. Shannon-Weiner's index for the degree of diversity was 2.898-3.666 in the area of upperstream, but 3.708-4.135 in downstream, which was little higher.

Production Dynamics of Phragmites longivalvis, Carex scabrifolia and Zoysia sinica Stand of a Sand Bar at the Negdong River Estuary (낙동감 하구 사구의 갈대, 천일사초 및 갯잔디군락의 생산능력)

  • Kim, Joon-Ho;Kyung-Je Cho;Hyeong-Tae Mun;Byeong Mee Min
    • The Korean Journal of Ecology
    • /
    • v.9 no.1
    • /
    • pp.59-71
    • /
    • 1986
  • Net production, dead material increments were measured, and annual respiration loss was simulated through a year to determine the gross production at the Phragmites longivalvis, Carex scabrifolia and Zoysia sinica stand on Okryudeung, a sand bar of the Nagdong river estuary. The maximum live biomass for above-ground organs of the three stands occured in October, i.e., 1, 985, 744 and 1, 013g/m2, and belowground net productions were estimated to be 650, 440 and 412g/m2, respectively. Materials died or shedding from live aboveground organs during the growth season were estimated to be 167, 81 and 0 g/$m^2$. From the results of simulation, annual variation of respiratiion was primarily dependent on the annual variation of temperature through a year. For annual respiration loss in three stands, 21.893, 6.147 and 5.036kg $CO_2/m^2$ were calculated, respectively. Corresponding gross productions were 72, 203, 22, 109 and 19, 909kcal/$m^2$. Respiration of belowground organs corresponded to 65%, 66% and 37% of the total plant respiration, and annual respiration loss accounted for 85%, 78% and 71% of the annual gross production. In view of efficiency of solar energy utilization, 5.8%, 1.8% and 1.6% of incident light energy were converted to gross production of plants during a year. With incident light energy during the growth season from April to September, energy utilizations for net production were estimated to be 1.2%, 0.4% and 0.6% at the three stands.

  • PDF

Distribution of Naturalized Plants at Stream in Middle Part of Korea (중부지방 하천의 귀화식물 분포)

  • Han, Jeong-Eun;Kim, So-Young;Kim, Won-Hee;Lee, Ji-Yeon;Kim, Joo-Hwan;Ro, Tae-Ho;Choi, Byoung-Hee
    • Korean Journal of Environmental Biology
    • /
    • v.25 no.2
    • /
    • pp.115-123
    • /
    • 2007
  • On the riparian zone of streams in the middle part of Korea, the distribution of naturalized plants was investigated. The species number and proportion of naturalized plants in each stream was increased from upstream to downstream of the stream and the highest proportion was observed at urban area of Jungryangcheon. A large number of naturalized plants has annual habit and European or North American origin. Highest similarity index of naturalized plants was observed between Hongcheongang and Naechoncheon. The percentage of herb plants showed positive relationship with that of naturalized plants in the steams, particularly high at the urban steam Jungryangcheon.