• Title/Summary/Keyword: 군락변화

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Spatio-Temporal Dynamics of Estuarine Wetlands Related to Watershed Characteristics in the Han River Estuary (유역특성에 따른 한강하구 습지의 공간분포 및 변화분석)

  • Rho, Paik-Ho
    • Journal of the Korean Geographical Society
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    • v.42 no.3 s.120
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    • pp.344-354
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    • 2007
  • Estuarine wetlands for 33 watersheds in the Han River estuary were delineated on topographic maps from the 1910s, 1970s, and 2000s. Then, these data were used to address the issue of spatial distribution and temporal variation. Watershed characteristics such as drainage density, location, watershed size, slope, and elevation were identified for each watershed to determine the relationship between watershed characteristics and spatial distribution of estuarine wetlands. The analysis of estuarine wetlands indicated that wetlands in the estuary had declined gradually between the 1910s and the 1970s, although most wetlands were lost since the 1970s mainly caused by the large development projects related to urban expansion in metropolitan Seoul. The sediment composition and formation processes of the wetlands differed with watershed location; mud flats dominate in the lower part of the estuary, and relatively more sandy and emergent-plant wetlands occur near the main channel and tributaries of the Han River. Relatively more estuary wetlands occur in large watersheds, which have high slopes and low elevations. Estuarine wetlands have been lost dramatically in the densely populated watershed regions (i.e., Han River Seoul, Han River Goyang, West Han River), while relatively more wetlands have remained in undeveloped regions, including the Lower Imjin River and Lower Han River. In particular, anthropogenic disturbance has played an important role in the loss of wetland through the conversion of wetland into agricultural and developed land.

Weeds on Rice Paddy Field of Jeonnam Western Region (전남지역 벼 재배방법에 따른 잡초 발생 특성)

  • Im, Il-Bin;Im, Bo-Hyeok;Park, Jea-Hyeon;Jang, Jeong-Han;Im, Min-Hyeok;Lee, In-Yong
    • Weed & Turfgrass Science
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    • v.4 no.4
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    • pp.295-307
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    • 2015
  • Surveys of weed species in paddy fields were conducted to identify weed occurrence on July 2013. Total 237 sites of paddy fields in 9 City/Gun, Jeonnam Provinces in Korea were investigated. From the survey, 45 weed species in 18 families were identified and classified to 33 annuals and 15 perennials. Based on the occurrence ratio, the most weed species belonged to Poaceae (9 species) and 8 and 4 weed species belonged to Cyperaceae and Scrophulariaceae, respectively. These 21 weed species in the most four families accounted for 46% of total weed occurrence. The most dominant weed species in Korean paddy fields were Echinochloa spp. (18.5%), followed by Monochoria vaginalis (12.3%), Lemna perpusilla (8.2), Eleocharis kuroguwai (5.2%) and Scirpus juncoides (5.2%). The most dominant weed species in machine transplanting paddy fields were Echinochloa spp. (14%), followed by Monochoria vaginalis (12%) and in water seeded rice paddy fields were Echinochloa spp. (25%), followed by Monochoria vaginalis (11%). This information could be useful for estimation of future weed occurrence, weed population dynamics and establishment of weed control methods in paddy fields.

A Study on the Image and Visual Preference for the Beautiful Forest Scenery types in Korea (아름다운 산림풍경 유형의 선호도 및 이미지 특성에 관한 연구)

  • Lee, Yeon-Hee;Park, Chan-Woo;Ha, Si-Yeon
    • Journal of Korean Society of Forest Science
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    • v.104 no.4
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    • pp.685-696
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    • 2015
  • This study intends to evaluate visual preference and image for 10 types of forest sceneries which have own distinct characteristics without overlapping each other among 22 types of beautiful forest sceneries based on Korea National Parks. Z scale and paired comparison methods were used to analyze visual preference for forest scenery, and SD scale method was also adopted to assess visual image for forest scenery. Experiments were conducted with 3 different university students groups. The results of this study can be summarized as follows. First, the evaluation results of Z scale (N=70) and paired comparison (N=64) methods show similar visual preference for different types of forest scenery. 'Scenery inside forests' and 'valley and rock' sceneries have the highest level of preference, and 'panorama of ridges', 'ridge of curious rock peaks', and 'waterfall and cliff' also have relatively higher preference level than others. However, 'community of dead trees' has the lowest preference in forest sceneries. Second, the factor analysis outputs of the image scores for beautiful forest scenery types by SD scale (N=66) show 3 factors of 'mysterious charm', 'colorful sense', and 'vividness/variety'. Examined the variables of forest scenery types for each factor, the image of 'mysterious charm' is based on the sceneries of mountain ridges, the image of 'colorful sense' is focused on the sceneries of color-expressed sense of the season, and the image of 'vividness/variety' is based on the sceneries of waterscape and curious rock peaks.

Distributional Patterns of Understory Vegetation at Mt. Geumdae's Protected Area for Forest Genetic Resources (금대봉 산림유전자원보호림의 하층식생 분포양상)

  • Chun, Seung-Hoon;Lee, Hyung-Sook;Lim, Jong-Hwan
    • Journal of Korean Society of Forest Science
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    • v.98 no.3
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    • pp.339-350
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    • 2009
  • This study was carried out to investigate distributional condition of rare plants and useful plant resources, and to verify distributional patterns of understory vegetation associated with the upper layer's vegetation structure. Total 59 families, 160 genera, 218 kinds of vascular plants were identified at the study site including 6 rare plants designated by Korea Forest Service (Lloydia triflora Bak., Trillium kamtschaticum Pall., Lilium distichum Nakai, Anemone koraiensis Nakai, Iris odaesanensis Y.N. Lee, Viola diamantica Nakai). Twenty three species of useful plant resources were also identified at the site; 8 of them showed clustered distributions and the others were prone to scatter. Actual vegetation of this study area consisted of one natural community dominated by Quercus mongolica Fisch. and three disturbed communities of Larix kaempferi (Lamb.) Carriere, Abies holophylla Max. and/or a herbaceous vegetation resulting from forest removal and strong wind of mountain top. This classification was strongly supported by cluster analysis based on the surveyed plot data. Distributional patterns of understory vegetation within forest stand were somewhat related to overstory vegetation structure, but showed a different tendency according to site condition, species composition, and competitive pressure among understory vegetation. Therefore, in order to protect the important understory components as forest genetic resources, forest treatments such as density control of overstory should be implanted based on understanding of impact on understory's dynamics and growing condition.

The Study for the Flora of 6 Islands Area in the Western Sea of Chungnam Province (충남 서해지역 6개 도서 지역의 식물상 연구)

  • Moon, Ae-Ra;Kim, Hyun-Jun;Park, Jeong-Mi;Kang, Shin-Ho;Jang, Chang-Gee
    • Korean Journal of Plant Resources
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    • v.25 no.1
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    • pp.105-122
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    • 2012
  • This study was carried out to illuminate the flora of vascular plants of islands at Chungnam. This study was conducted from March to November, 2010. Based on the voucher, vascular plants of in investigated islands were 105 families 326 genera 454 species 4 subspecies 45 varieties 9 forms, totally 512 taxa. Korean endemic plants were 6 species such as Aster koraiensis, Salix koriyanagi, Indigofera koreana, Hemerocallis taeanensis, Hepatica insularis, Philadelphus schrenckii, rare and endangered plants of designated by Korea Forest Service were 4 taxa, such as Magnolia kobus (planted), Koelreuteria paniculata, Berchemia racemosa var. magna, Glehnia littoralis respectively. Phytogeographical special plants were totally 69 taxa, which were grade I of 50 taxa, grade II of 1 axon, grade III of 11 taxa, grade IV of 4 taxa, and grade V of 3 taxa. 14 southern plants and 4 northern plant by criterion from climate change study were found in this area. Naturalized plants were 17 families 46 taxa, that was 9.1% of total vascular plants in this area. Even naturalized plants has not influence on the islands vegetation. However, regular passenger ferry between islands and increasing of visiter will be affecting vegetation.

Gall formation on different age, habitat, and parasite position in Rhus javanica L. (붉나무의 수령, 서식지 및 기생위치에 따른 오배자 형성)

  • Jo, Hyeong-Chan;Han, Kwang-Soo;An, Eun-Yong
    • Korean Journal of Medicinal Crop Science
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    • v.8 no.4
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    • pp.304-311
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    • 2000
  • This study was conducted to investigate the ratio and number of the Rhus javanica gall formed by chinese sumac aphid, Scheleechtendalia chinensis, in several different conditions in which R. javanica lives. The density of 11 to 15-year-old R. javanica was more higher and the number of galls was also higher than 1 to 5- or over 16-year-old one at these sites. The formed gall according to four directions such as the East, West, South and North was founded the highest at the East and followed South, North, and West order. The formative rate of R. javanica gall did not differ in the mixture forest, and in the habitat having a heap of a little stone and mosses near a valley was better than in the site of road perimeter. Through an index of the gall diameter and the number of chinese sumac aphid, we evaluated the gall processing and development formed by the aphid. As the density of aphids increase, the size of the gall was also more plumped. The part of phyllotaxy of R. javanica gall in leaf and pinnate of was increased in the middle and upper part of terminal leaflet and leaflet was more occupied than wing. R. javanica which did not form a gall in natural environmental, formed gall by a artificial inoculation of S. chinensis. Some gall disappeared during a gall development from various environmental conditions.

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The Study of Distribution Changing and Community Characteristics of Daphniphyllum macropodum (National Monument No. 91) in Naejangsan National Park (내장산국립공원 굴거리나무군락의 군집특성 및 분포 변화 연구)

  • Shin, Jin-Ho;Jeon, Yong-Sam;Son, Ji-Won
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.19 no.3
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    • pp.45-57
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    • 2016
  • This study was focused on the northernmost limit of the distribution changing of Daphniphyllum macropodum and studied characteristic of plant communities of natural monument No. 91 in Najangsan national park, Korea. The results of this study were as follows : 1. The highest importance percentage(I.P.) value at tree layer in Quercus. mongolica community was Q. mongolica, 37.8%. But the highest value of mean importance percentage(M.I.P.) was D. macropodum, 32.8%. 2. The highest I.P. value at tree layer in Carpinus laxiflora community was C. laxiflora, 47.4%. The highest M.I.P. value was C. laxiflora, 28.8% and M.I.P. value of D. macropodum was 24.0%. 3. The highest I.P. value at tree layer in D. macropodum community was D. macropodum, 55.6%. C. laxiflora and Q. mogolica I.P. value was 14.8% and 6.8%, respectively. The highest M.I.P. value was D. macropodum, 47.9%. Sapium japonicum and C. laxiflora M.I.P. value was 11.4% and 10.7%, respectively. 4. The highest I.P. value at tree layer in Quercus variabilis community was C. laxiflora, 20.8%. Q. variabilis and Acer pseudosieboldianum I.P. value was 15.3% and 12.5%, respectively. The highest M.I.P. value was D. macropodum, 21.5%. It needs to the continuous monitoring of vegetation and importance percentage change in tree layer and subtree layer of D. macropodum. The researching results of D. macropodum distribution, the distribution range of D. macropodum showed expanded more than range of Lim and Oh' result(1999). In other words, it was distributed low density level between Najangsa temple and Byeokryeonam, and distributed in upper Keumsun waterfall and Wonjeok upper valley. D. macropodum was appeared on hiking trails around from Wonjeokam to Bulchulbong. Especially, it was found in this study that D. macropodum was distributed on Seoraebong's north which placed outside area of Naejangsa region. In this study, it was considered that distribution range of D. macropodum was expanded. Also, it is expected to be used as a result of the field study of changing distribution study of broad leaved evergreen forest due to global warming.

Current Status and Direction of Weed Management According to Cropping Systems (작부체계에 따른 잡초관리 연구 동향과 방향)

  • Lee, Jihyun;Shin, Myeong-Na;Ku, Bon-Il;Shim, Kang-Bo;Jeon, Weon-Tai
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.66 no.4
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    • pp.459-466
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    • 2021
  • The present study was conducted to propose future research directions for weed management by examining the current trends of research on weed occurrence according to cropping systems. The cropping systems are developed for the efficient use of arable land, and the weed flora changes according to the management practices of a given cropping system. In particular, weed occurrence can be reduced by altering the soil environment. In addition, cultivation methods, such as tillage, affect the weed seed bank in the soil, thus altering the pattern of weed occurrence. Here, we propose three weed management practices according to the cropping system. First, it is necessary to develop a model that can classify weed species by analyzing young seedlings and can predict the flora in the field. Second, it is important to manage the cropping system history and establish a database of agricultural information, which can be linked to meteorological and geographic data. Third, it is critical to estimate the weed occurrence and soil seed bank dynamics, based on which a cropping system platform and digitalization technology can be developed. In the future, the prediction of weed occurrence and control according to the cropping system will contribute to sustainable agriculture by reducing the use of herbicides and solving the problems of resistant weeds.

Studies on the Variation of Vegetation and Rice Root Formation Accompanied with the Desaltation at the Reclaimed! Tidal Fields (간척지의 제염정도에 따른 식생의 변이의 수도근모형성에 관한 연구)

  • Kwon. H.J.;Chung, W.I.;Cho, J.Y.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.28 no.3
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    • pp.305-309
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    • 1983
  • To know the effect of desaltation in the reclaimed tidal fields on the succession of vegetation and on the root hair formation of paddy rice, reclaimed fields in Kang Hwa Island, Nam-Yang Bay and Ke-Hwa Island were investigated during summer crop season in 1982. The obtained results can be summarized as followings. l) In the highly salty and water logged areas of reclaimed tidal fields, the first dominating species of higher plant were observed to be Salicornia herbacea L. and Suaeda japonica Makino. With the continued desaltation, Chemopodium virgatum Thumb. occurred in the vegetation. After this transition, the dominating species were composed of Scirpus maitimus L. and Phragmites communis Trin. At the S. maitimus and P. communis dominating salinity level, rice cultivation was safe from the salt damage. 2) In the water logged area, Artemisia capillaria Thunb. and Aster tripolium L. took the place of dominating species after S. herbacea and S. japonica. At this salinity level, graminaceous weeds began to immigrate. 3) In dry areas, Suaeda asparagoides Makino and Suaeda maritima were the first appearing dominant species. Atriplex subcordata Kitakawa was also observed in sucy dry areas, but colony formation was not observed. 4) Plants immigrated slowly into dry areas from the already vegetated water logged areas with the continuation of desaltation. 5) The high soil salinity level affected the root hair formation of rice by reducing both the rate of root hair formation and the length of root hairs.

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Ecological Characteristics and Their Implications for the Conservation in the Taehwagang River Estuarine Wetland, Ulsan, South Korea (울산 태화강하구습지의 생태적 특성 및 보전을 위한 제안)

  • Pyoungbeom Kim;Yeonhui Jang;Yeounsu Chu
    • Ecology and Resilient Infrastructure
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    • v.10 no.4
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    • pp.171-183
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    • 2023
  • Estuarine wetlands, which form a distinctive brackish water zone, serve as important habitats for organisms that have adapted to and thrive in this environment. Nonetheless, excessive development and utilization result in artificial disruptions that alter the distinctive functions and attributes of estuarine wetlands. To collect the basic data for the conservation of estuarine wetlands with excellent ecosystems, we investigated the vegetation distribution characteristics and biota status of the Taehwagang River Estuarine Wetland. Data from vegetation surveys have shown that 25 plant communities of six physiognomic vegetation types, including willow vegetation, lotic and lentic herbaceous vegetation, floating/submerged vegetation. In the upper reaches, where topographical diversity was high, various types of wetland vegetation were distributed. In terms of biodiversity, a total of 696 species, including 7 endangered wildlife species, were identified. Due to good ecological connectivity, tidal rivers are formed, brackish water species including various functional groups are distributed around this section. The inhabitation of various water birds, such as diving and dabbler ducks, were confirmed according to the aquatic environment of each river section. The collection of ecological information of the Taehwagang River Estuarine Wetland can be used as a framework for establishing the basis for conservation and management of the estuarine ecosystem and support policy establishment.