• Title/Summary/Keyword: Ecological Factors

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An Analysis of Growth Status and Soil Environment in Camellia japonica L. Forest at Jeolla-province Natural Monuments (동백나무 숲의 생육현황 및 토양환경 분석 - 전라도 지방 천연기념물 동백나무 숲을 중심으로 -)

  • Lee, Won-Ho
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.31 no.3
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    • pp.1-11
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    • 2013
  • In this study, based on a natural monument forest research by Camellia japonica L. Forest appointed as a natural monument located environment and growth environment and the soil environment, Camellia japonica L. Forest soil in order to analyze effects of soil in Camellia japonica L. Forest correlation analysis the results can be summarized as follows: First, a natural monument Camellia japonica L. forest located on the foot of a mountain valley or within the stream, a lot of sunshine southeast, east, and south in the direction of the share due to external factors, making it a good, but, $15{\sim}30^{\circ}$ of distributed in the soil slopes in the slope there is a risk of loss are appearing. Second, the growth of the Status of Camellia japonica L. forest represents the distribution of the uneven-aged forest diameter class. but increases the density of the upper forest trees Camellia japonica L. occurred in lower saplings do not have growth. The width of crown diameter class caused a narrow oppressed tree, the average tree height in the 8.09m, camellia in common was lower than that of tree height, variation diameter class in the width of crown distribution severe low correlations were analyzed. Third, the natural monument Camellia japonica L. forest soil composition, properties of soil pH, etc. 10 entries were analyzed components of the soil. In summary analysis properties of soil, soil pH, calcium, organic matter, magnesium was good and potassium content was insufficient, nitrogen and phosphorus were excess. Fourth, the growth condition of Camellia japonica L. forest and soil physicochemical properties, the results of the correlation analysis. magnesium, calcium, nitrogen affects the growth of Camellia japonica L. forest. Other seven kinds of items showed no effect on growth. Current Status and Future Growth of Camellia japonica L. forest soil and soil environments as well as the relationship between, Camellia Forest Factors affecting the growth of the state in terms of long-term ecological research and conservation status of settled Camellia japonica L. forest research for building materials there will be continued.

Distribution and Community Structure of Salix Species along the Environmental Gradients in the Nam-River Watershed (남강 유역에서 환경 구배에 따른 버드나무속의 분포와 생태적 지위)

  • Lee, In-Soon;Lee, Pal-Hong;Son, Sung-Gon;Kim, Cheol-Soo;Oh, Kyung-Hwan
    • The Korean Journal of Ecology
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    • v.24 no.5
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    • pp.289-296
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    • 2001
  • Community structure of the Salix and physico-chemical properties of sediment were studied from July to September, 2000 in Nam-River watershed for the purpose of inquiring niche breadth, niche overlap and the environmental factors affecting the distribution of Salix species. Among eleven Salix species, the dominant species was Salix koreensis, while the rests were such order as S. nipponica, S. gracilistyla and S. glandulosa by the relative abundance based on the basal area. Mean values and the ranges of sediment properties such as pH, conductivity, water content, organic matter, total nitrogen, available phosphorus, clay, silt and sand were 5.3∼6.3, 14∼351 μmho/cm, 0.1∼3.4%, 0.5∼7.3%, 0.01∼0.2%, 0.1∼0.4 mg/100 g, 1.7∼22.0%, 0.2∼40.8%, 39.7∼98.0%, respectively. Altitude and annual mean temperature of each site were 20∼620 m and 9.3∼13.0℃, respectively. Niche breadth was estimated by considering the differences of the soil texture as the differences of state of source. S. glandulosa was the broadest at the level of 0.77, while the rests were such order as S. koreensis, S. nipponica were 0.69, 0.54, respectively. The niche overlap showing the level of interspecific competition was the largest as 0.94 between S. purpurea var. japonica and S. purpurea var multinervis, while S. graciliglans and S. purpurea var. japonica 0.92, S. graciliglans and S. purpurea var. multinervis 0.87, respectively. According to the analysis of the correlation between eleven species of Salix and eleven environmental factors, S. gracilistyla showed the negative correlation with conductivity, water content, total nitrogen, clay, silt and annual mean temperature, and showed the positive correlation with total nitrogen, sand and altitude. S. graciliglans showed the negative correlation with conductivity, water content, organic matter, clay, silt and annual mean temperature, and showed the positive correlation with total nitrogen, sand and altitude. S. nipponica showed the negative correlation with sand and altitude, and showed the positive correlation with water content, total nitrogen, clay, silt and annual mean temperature. S. nipponica showed the opposite results of S. gracilistyla. Soil texture, total nitrogen, water content, altitude and annual mean temperature were affecting the distribution of Salix species in Nam-River watershed.

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Dendrochronological Analysis of Abies koreana W. at Mt. Halla, Korea: Effects of Climate Change on the Growths (한라산 구상나무(Abies koreana W.)의 연륜연대학적 연구 - 기후변화에 따른 생장변동 분석 -)

  • Koo, Kyung-Ah;Park, Won-Kyu;Kong, Woo-Seok
    • The Korean Journal of Ecology
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    • v.24 no.5
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    • pp.281-288
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    • 2001
  • The relationships between the growths of Abies koreana W. and climatic factors were analyzed by the use of tree-ring analysis at the subalpine belt of Mt. Halla National Park. The four cores were extracted from each 21 trees at north-facing slope (1,900m a.s.1.). The site chronology was established on the periods from 1912 to 1999. The growth of A. koreana was very poor, in particular in the years of 1982, 1988 and 1996. Simple correlation was employed to analyze the relationship between the growth of A. koreana and climatic factors. The result of simple correlation indicates that the growth of A. koreana represent positive correlations both with the mean temperatures of April and previous November, and the precipitation of previous December and January. The presence of large number of frost-damaged scars in the individual trees of A. koreana implies that local freezing temperature conditions at Mt. Halla have occurred in 1964, 1965 and 1966. The correlations between the fir chronology SOI(Southern Oscillation Index) of previous January, February and November were significantly positive. The growth ratio of A. koreana demonstrates that this species is sensitive to seasonal variations. As the winter temperature rises, the growth ratio of A. koreana decreases, on the other hand, the increase of autumn temperature accelerates the growth ratio of A. koreana. The growth decline of A. koreana was observed from 51 cores out of the 54 cores, and the overall growth declines have initiated at 1978, 1982 and 1988. Distinct growth decline of A. koreana in the range of 70% is noticed at 34 cores out of the 51 cores. The decline of, A. koreana growth appears to be related to the winter temperature which has increased since mid-1970s.

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Physio-ecological Characteristics of Sagittaria trifolia L., a Perennial Weed in Paddy Field 1. Effect of Environmental Factors on Emergence of Tuber of S. trifolia (논 다년생잡초(多年生雜草) 벗풀의 생리생태적(生理生態的) 특성(特性)에 관한 연구(硏究) - 1. 벗풀 지하경(地下莖)의 출아특성(出芽特性))

  • Han, S.S.;Ryang, W.J.
    • Korean Journal of Weed Science
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    • v.12 no.1
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    • pp.8-15
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    • 1992
  • Arrowhead (Sagittaria trifolia L.), a perennial weed dominant in paddy field, is considerably difficult to control by herbicides. The investigation on the effects of environmental factors on emergence of arrowhead tuber can aid for controlling this weed. The results exmined were as follows : From the results of emergence characteristics at different levels of temperature, arrowhead tuber could germinated at 15$^{\circ}C$-40$^{\circ}C$. The optimal temperature for basal emergence was ranged from 25 to 30$^{\circ}C$. Basal emergence at 15$^{\circ}C$ and 20$^{\circ}C$ began at 56 and 12 days after tuber plantation, respectively and were later than those at the optimal temperature. At the different levels of shading, all the tested tubers could emerged. The days required for basal emergence at 25% and 50% shading plots were shorter than those at 70%, 80% and non-shading plots. The basal emergence was more effective under blue and clear films than any other phyto-selective materials. Some of arrowhead tubers could not emerged under green, red and yellow films. On the soil pH, the basal emergence was best at soil pH 6.0 and 7.0. At soil pH 4.0, 5.0 and 8.0, the required days for emergence were longer than those at soil pH 6.0 and 7.0 and some of tubers could not emerged. Arrowhead tubers more then 0.5 g showed the shorter shooting days than those less than 0.5 g. Tubers were able to emerge at water depth ranging from 0 to 20 cm. At 3 cm and 5 cm water depth, the required days for basal shooting were shorter than those at any other levels of water depth. The emergence of basals was best at molding depth of 0 cm, and the rates at 3 to 5 cm of plantation depth were decreased. At 10 cm plantation depth, the shooting rate was significantly decreased.

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A Study on the Phonology of the Striped Rice Borer, Chilo suppressalis (Walker), in Relation to the Introduction of New Agricultural Practices (경종법에 변천에 따르는 이화명나방 발생상의 변동에 관한 연구)

  • Song Yoo Han;Choi Seung Yoon;Hyun Jai Sun
    • Korean journal of applied entomology
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    • v.21 no.1 s.50
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    • pp.38-48
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    • 1982
  • This study was conducted to investigate the changes in moth occurrence of striped rice barer, Chilo suppressalis (Walker), in relation to climatic factors, rice varieties, and cultural practices. The light trap data from 41 forecasting stations for 14 years from 1966 to 1979 were analyzed by means of the changes in the time and amount of borer occurrence in connection with the introduction of new rice varieties, the accumulated effective day-degree and its variation for completing one generation, and the climatic factors affecting the moth occurrence. The total number of moths caught by light traps in both spring and summer generations were considerably decreased with the wide cultivation of new rice varieties. In fact, the spring moths were remarkably decreased since the new varieties were introduced in 1972. The occurrence ratio of summer moths against the preceeding spring moths was higher in the middle region and middle southern mountainous area than the other regions. Its high ratio of regions was annually expanded from the middle region to the southern region. The $50\%$ emergence dates of both generations were later in the southeastern region than in the middle region. The ecological characteristics were clearly shown between the northern and southern region of Chupungryeong in terms of the occurrence of summer moths, the ratio of occurrence of summer moths to the preceeding spring moths, and $50\%$ emergence dates of the summer moths during the years of $1977\~1979$. The ratio of the summer moth occurrence to the preceeding generation was negatively correlated with the average temperature in lune and July, respectively, and the average precipitation in late June. The ratio of spring moth occurrence over the preceeding generation was positively correlated with the average temperature in September, October, November, and March, respectively, whereas it was negatively correlated with the average precipitation in early September and March, and the average humidity in early May. The effective day-degree for one generation was in the range from 600 to 900 DD at upper threshold $30^{\circ}C$ and lower threshold $10^{\circ}C$.

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Trend Analysis of Strategic Factors to Promote the Image of Cities (도시별 이미지 전략 요인의 경향 분석)

  • Byeon, Jae-Sang
    • Journal of the Korean Institute of Landscape Architecture
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    • v.36 no.2
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    • pp.80-98
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    • 2008
  • In the past, the purpose of urban landscape planning was to beautify cities. Now, that is changing as cities with their own characteristic identities and images are focusing on the making of livable cities. The subject of international competition is turning from a country objective to that of individual cities. To increase the attraction of the urban image will, therefore, be the most important and urgent policy in all cities. A city without global competitiveness will be demoted to a sub-city. This study intends to suggest strategic ways to improve the urban image suitable for Korean cities by the analysis and classification of the advanced cases in other countries. This study can be summarized as follows: 1. The image of cities is promoted by diverse strategies such as establishing landmarks, making meaningful places, hosting festivals and sports events, and making cultural policies. These strategies can be classified by three factors: the landscape and ecological factor, the historical and cultural factor, and the administrative and economic factor. 2. Korean cities are making efforts to promote their images through a variety of ways. Mega cities in Korea are steadily carrying out projects to use the administrative and economic factor such as expanding the infrastructure, supporting enterprises, advertising and marketing with accumulated capital. However, local small cities mainly depend on festivals and simple events or programs that are of interest but which lack characteristic identity. 3. Cities of advanced western countries are upgrading their images by finding and applying strategic methods to reflect characteristic identity and to keep in step with the changes of the times. On the other hand, cities in Japan try to promote urban image with traditional native festivals and with the making of livable places based on resident participation. The central government in Korea needs to establish a master plan considering the regional balance to improve the image of each city. Local governments should carry out these diverse strategic methods. The task after benchmarking advanced cities with beautiful landscapes will be to find an 'All-Korean Style' and apply it to cities with characteristic image.

The Topographical Factors Affecting the Water Quality of Iwonchon Basin (이원천 유역의 하천수질에 미치는 지형요인)

  • 이호준;방제용
    • The Korean Journal of Ecology
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    • v.22 no.3
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    • pp.101-108
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    • 1999
  • This survey was performed from March 1993 to March 1998, in order to clarify the relationships between water quality and topographical factor. The study sites were two reservoir basins; Kaesim and Jangchan in Iwon-myon, Okchon-gun, Chungcho'ngbukdo Province. Basin shape factors of Kaesim reservoir were at 0.030∼0.210 (mean value 0.090), those of Jangchan reservoir were at 0.217∼0.452 (mean value 0.325). The mean basin shape factor of Jangchan reservoir was 3.61 times larger than that of Kaesim reservoir because its stream width was narrower and mean stream length was shorter. In the correlation between distance from the source of stream (L) and basin area (A), Iwonchon basin was calculated as L=1.44A/sup 0.6/. Circularity ratio was 17.114 in Kaesim (22% of Kum River), and 7.444 in Jangchan. Elongation ratio was 0.357 in Kaesim, 0.636 in Jangchan and 0.282 in Kum River. Precipitation summation period of Jangchan was 1.54 times slower than that of Kaesim. Rainfall reaching time in each small basin was 337.53 min. in A'(Jangchan-ri) basin of Jangchan and 49.26 min in H (Iwon-ri) basin of Kaesim. In the relationship between watershed frequency (Df) and drainage density (Dd), the regression equation was Df=0.023Dd² in Kaesim and Df=0.189Dd² in Jangchan reservoir. As slope degree increased, DO became higher (Y/sub DO/=0.19X+6.5927, r=0.8l), but COD(Y/sub COD/=-0.2092X+9.7104, r=0.52) became lower. Total nitrogen was increased with the increase of basin shape factor and circularity ratio. Ratio of B/sub OD/ to COD was 1/1.2(Y/sub BOD/ = 1.2984 X/sub COD/-3.2004, r=0.9l).

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The Analysis of Vegetation-Environment Relationships of the Coniferous Forests in Subalpine Districts of Mt. Chiri by TWINSPAN and CCA (TWINSPAN 및 CCA에 의한 지리산(智異山) 아고산대(亞高山帶) 침엽수림군집(針葉樹林群集)과 환경(環境)의 상관관계(相關關係) 분석(分析))

  • Lee, Soo Won;Lee, Kang Young;Song, Ho Kyung
    • Journal of Korean Society of Forest Science
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    • v.86 no.3
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    • pp.279-287
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    • 1997
  • This study was carried out to identify the analysis of vegetation-environment relationships of the coniferous forests in subalpine districts of Mt. Chiri by two-way indicaton species analysis(TWINSPAN) and CCA. The results are summarized as follows; The subalpine coniferous forest in Mt. Chin was classified Abies koreana community group by the TWINSPAN method. The Abies koreana community group was classified Abies koreana-Pinus densiflora, Abies koreana-Quercus mongolicd and Abies koreana-Picea jezoensis. The Abies koreana-Quercus mongolica community classified into two subcommunities, typical and Pinus koraiensis subcommunity. The Abies koreana-Picea jezoensis community classified into three subcommunities such as typical, Taxus cuspidate and Cornus controversa subcommunity. The subalpine conifers commnities in Mt. Chiri could be classified into six vegetation units, which consisted of three vegetation communities and five subcommunities. The relationship between vegetation community and influencing environmental factors was analyzed by using the CCA ordination method. It was found that altitude, concentrations of $Ca^{++}$ and $Mg^{++}$ in soil were, major environmental variables, which influence the distribution of vegetation community in the first axis, and $Ca^{++}$ and altitude in the second axis. In the relations of communities and environmental factors by CCA, the optimal ecological habitats of Abies koreana-Pinus densiflora community could be located at low elevations, in which $Ca^{++}$ and $Mg^{++}$ are rich. Abies koreana-Quercus mongolica community prefers the sites in mid-elevation zone, in which $Ca^{++}$ and $Mg^{++}$ are medium level in soil. The optimum site for Abies koreana-Pinus koraiensis community and Abies koreana-Taxus cuspidata community could be high elevations in which $Ca^{++}$ and $Mg^{++}$ are poor. Abies koreana-Cornus controversa community is found in the site at low elevations where $Ca^{++}$ and $Mg^{++}$ are medium.

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Environmentally Associated Spatial Distribution of a Macrozoobenthic Community in the Continental Shelf off the Southern Area of the East Sea, Korea (한국 동해 남부해역 대륙붕에 서식하는 대형저서동물군집 공간분포를 결정하는 환경요인)

  • Lee, Jung-Ho;Lee, Jung-Suk;Park, Young-Gyu;Kang, Seong-Gil;Choi, Tae Seob;Gim, Byeong-Mo;Ryu, Jongseong
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.19 no.1
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    • pp.66-75
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    • 2014
  • This study aims to understand environmental factors that determine spatial distribution of macrozoobenthic community in the southern area (ca 100-500 m depth) of East Sea, Korea, known as a candidate site for carbon storage under the seabed. From sixteen locations sampled in the summer of 2012, a total of 158 species were identified, showing density of $843indiv/m^2$ and biomass of $26.2g\;WW/m^2$, with increasing faunal density towards biologically higher diverse locations. Principal component analysis showed that a total of 33 environmental parameters were reduced to three principal components (PC), indicating sediment, bottom water, and depth, respectively. As sand content was increasing, number of species increased but biomass decreased. Six dominant species including two bivalve species favored high concentrations of ${\Omega}$ aragonite and ${\Omega}$ calcite, indicating that the corresponding species can be severely damaged by ocean acidification or $CO_2$ effluent. Cluaster analysis based on more than 1% density dominant species classified the entire study area into four faunal assemblage (location groups), which were delineated by characteristic species, including (A) Ampelisca miharaensis, (B) Edwardsioides japonica, (C) Maldane cristata, (D) Spiophanes kroeyeri, and clearly separated in terms of geography, bottom water and sediment environment. Overall, a discriminant function model was developed to predict four faunal assemblages from five simply-measured environmental variables (depth, sand content in sediment, temperature, salinity and pH in bottom water) with 100% accuracy, implying that benthic faunal assemablages are closed linked to certain combinations of abiotic factors.

Shear Strength and Erosion Resistance Characteristics of Stabilized Green Soils (토양안정재를 혼합한 녹생토의 전단강도 및 침식저항특성)

  • Oh, Sewook;Jeon, Jinchul;Kim, Donggeun;Lee, Heonho;Kwon, Youngcheul
    • Journal of the Korean GEO-environmental Society
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    • v.16 no.12
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    • pp.45-52
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    • 2015
  • With the rising interest in the environment, more attention on ecological restoration for damaged slope surface to restore its original state has been drawn. Generally, the most useful method is vegetation based spray work. This method uses green soil including sewage sludge, sawdust, paper sludge, and weathered granite soil. However, because there are neither accurate information nor test values about green soil, green soil is often lost by environmental factors such as rainfalls and strong winds. To solve the problem of green soil, it is necessary to prepare design standards about green soil, and conduct studies to deal with green soil loss in consideration of various variables including basic material property, soil quality of slope surface, and weather. This study was conducted in the mixture of green soil and eco-friendly soil stabilizer. With green soil, basic material property test and compaction test were conducted for the analysis on the basic characteristics of green soil. In the mixture with soil stabilizer at a certain ratio, we conducted shear strength test depending on the ratio in order to analyze the maximum shear strength, cohesion and the change in internal friction angles. Furthermore, in the mixture ratio of green soil and soil stabilizer, which is the same as the ratio in the shear strength test, an inclination of slope surface was made in laboratory for the analysis on erosion and germination rate. Finally, this study evaluated the most effective and economic mixing ratio of soil stabilizer to cope with neighboring environmental factors. According to the test, the shear strength of green soil increased up to 51% rely onto the mixing ratio of and a curing period, and its cohesion and internal friction angle also gradually increases. It is judged that the mixture of soil stabilizer was effective in improving shear strength and thereby increased the stability of green soil.