• Title/Summary/Keyword: fallen leaves

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Effect of Nitrogen Rate on the Ionic Balance and the Variance with Leaf Sequance in Mulberry (Morus alba L.) Leaves (시용질소양이 상엽중 이온 균형 및 엽위별 변화에 미치는 영향)

  • 이운주
    • Journal of Sericultural and Entomological Science
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    • v.24 no.2
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    • pp.43-54
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    • 1983
  • In a field trial, the influence was studied by measurement of growth and leaf yields and chemical composition (in organic cations and anions and total nitrogen) with two nitrogen dressings (lower nitrogen treatment 25kg and higher nitrogen treatment 75kg urea/10a as the summer fertilizer) after the summer cutting. The results were as follows; 1. With increasingn nitrogen dressing, branch length and weight were enchanced. The fresh weight of leaves was higher to be 273.6kg/10a in the higher nitrogen treatment than in the lower nitrogen treatment on 20 September. 2. The moisture content of leaves lasted above 73% until on 30 August. Afterward it decreased sharply upto 63% on 20 September. In higher nitrogen treatment it was higher about 0.1∼1.8% than in lower nitrogen treatment. The increasing nitrogen dressings combined with leaf condition led to be soft until on 10 October. 3. Dry matter weight of leaves started decreasing around on 10 September, whereas that of branches increased until around 30 September indicating that the dry matter moved to branch and root from leaves. 4. The increase in Ca$\^$2+/ content was particularly evident, whereas the K$\^$+/ and Mg$\^$2+/ decreased with growth. The Ca$\^$2+/ content was much higher in the high nitrogen treatment than in the low nitrogen treatment. 5. With rapid decrease in total nitrogen and water in the leaves around the end of August, the Ca$\^$2+/ and Cl$\^$-/ which were higher in the lower part moved up to the upper part. Whereas the K$\^$+/, H$_2$PO$_4$$\^$-/ and SO$_4$$\^$2-/ which were higher in the upper part moved down to the lower part. 6. Total nitrogen content decreased sharply 3,200me/kg DM to 2,000me/kg DM at the end of August changing the maxmium content of total nitrogen from upper to lower part in the low nitrogen treatment on 12 September and in the high nitrogen treatment on 22 September, and an apex of branches was died and fallen 10 days after respectively. 7. The sum of cation in leaves (∑C) increased from 1400me/kg DM to 1600me/kg DM with growth, wherease that of anions (∑A) was approximatly the same during the whole growing season. As the result, the ionic balance (C-A) increased from 1000me/kg DM to 1200me/kg DM. 8. ∑C, ∑A and (C-A) were higher in the high nitrogen treatment than in the low nitrogen treatment due to be much higher of Ca$\^$2+/ content and higher of NO$\^$-/$_3$, SO$\^$2-/$_4$ and H$_2$PO$_4$$\^$-/ content.

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A Study of Calory Analysis Methods about Surface Fire Fuel (지표화 연료의 열량분석에 관한 실험방법 연구)

  • Kim, Jang-Hwan;Kim, Eung-Sik;Park, Hyung-Ju;Lee, Myung-Bo;Kim, Dong-Hyun
    • Fire Science and Engineering
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    • v.22 no.3
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    • pp.258-264
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    • 2008
  • This study proposes the experimental methods which shows various guidelines for systematic study of surface forest fuels. The thermal characteristics of surface fire fuels such as Quercus Variabilis and Pinus Densiflora fallen leaves are measured using TGA and Oxygen Bomb Calorimeter. Both of them are common species of Korean forest. Also the combustion characteristics of surface fire fuels are analysed according to the methods which are commonly used in Pool Fire analysis. The measured parameters are gas velocity, temperature, flame height, heat release rate and mass loss rate. A system is designed to simulate the surface fire. Methods and results are shown for the application of forest fire study.

Taxonomical History of Korean Mushrooms

  • Seok, Soon-Ja;Jin, Yong-Ju;Yoo, Ki-Bum;Hong, Seung-Beom;Kim, Yang-Sup
    • 한국균학회소식:학술대회논문집
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    • 2015.05a
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    • pp.19-19
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    • 2015
  • The term of Mushrooms means to spread like the April showers. After 18th century, the mycelium and spores of mushrooms were observed by microscope and then was denominated as fungi. About one hundred thousand species of mushrooms in appearance were worldly reported, and in Korea about four thousand species of mushrooms are estimated. In Korea, total of one thousand nine hundred one species of mushrooms have been recorded. Mushrooms belonging to the group of organisms called fungi, which must obtain their food from living plants or animals or from their remains after death. A large number of mushrooms grow in association with the roots of trees and other woody plants, called mycorrhizal fungi, both mushrooms and plants require this relationship for growth and development. And also many Mushrooms are saprobic, living on decayed various fallen leaves, twigs, trees and vegetable remains and etc. some of these million of spores settles on the proper habitat, these spores germinates and grows into a mass of threads, then a mycelium. This is the vegetable part of the mushrooms, what we call mushrooms are the carpophores, all the characteristics of the morphological features are appropriately used to identify species of mushrooms. Recently, identification and classification of mushrooms are newly confirmed by molecular analysis. In 2013, One thousand nine hundred one species of mushrooms in "List of Mushrooms in Korea" which published by the Korean Society of Mycology were recorded. Total of 238species, 107genera, 40families, 13orders, 6Classes belong to phylum Ascomycota. Total of 1,663species, 403genera 81families, 18orders, 7classes belong to phylum Basidiomycota.

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A COMPARATIVE STUDY OF GRAZING BEHAVIOUR OF TEDDY GOATS VERSUS THALLI SHEEP

  • Wahid, A.;Hanjra, S.H.;Iqbal, A.;Raza, S.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.5 no.4
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    • pp.681-685
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    • 1992
  • Experiment involved range vegetation classified into three major classes: Xerophytic trees, shrubs and grasses. Among them samples of major plant species were collected and analysed for chemical composition. The experimental animals 20 each of Thalli sheep and Teddy goats, located at Livestock Experiment Station Rakh Kharewala district Layyah (Pakistan) were randomly drawn from the main flock. The grazing pattern data were collected from one animal of each species. The observations regarding the grazing behaviour, breeding efficiency and carcass quality were also determined. It was found that overall preference index of Teddy goats were higher for Khabble (Cynodon dactylon) indicated by percent of the total number of bites made on different plant species, while the bites on Lumb (Aristida plumose), Mahabbat booti (Cenchrus biflorus), Dhaman (Cenchrus ciliaris) and Karera (Elionorus hirsutus) were found to be 1.28, 6.74, 0.32 and 3.87 percents. The browsing species as a whole were utilized more during the draught period. Among the grasses, sheep heavily utilized Khabble grass, with overall bite percentage of 89.27. Within browsing species Wan (Salvadora oleoides) and wind fallen dry leaves of Wan were considerably picked by the sheep showing 1.19 and 3.49 overall bite percentage respectively. The overall daily growth rates & dressing percentage for Teddy goats and Thalli sheep were 48.33, 39.00 and 51.00, 46.00 percent respectively. Moreover, among the experimental animals 50 percent goats exhibited signs of oestrus where as none of the sheep came into heat during the study period.

Studies on the Growth Environment of Calanthe Species Native to Cheju Province (제주(濟州) 자생(自生) 새우난초의 생육환경(生育環境))

  • Hyun, Myung-Ryuk;Choi, Ji-Yong;Suh, Jung-Nam;So, In-Sup;Lee, Jong-Suk
    • Horticultural Science & Technology
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    • v.17 no.4
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    • pp.494-496
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    • 1999
  • Natural habitats for Calanthe species were generally established in forests of deciduous broad-leaved trees. The habitat areas had lower summer temperatures, more precipitation, and harrow humidity ranging 75~90% throughout the year than adjacent non-habitat areas. The most influential factor on the habitat establishment was light intensity. The light levels in the habitats are cut down by tree canopies, which also reduce temperature before the defoliation in autumn. The most frequent distribution of the habitat was in the areas with light intensity of 400~1,500 lux under tree canopies and of 30,000~50,000 lux in winter after defoliation. Calanthe was characteristically distributed in the broad-leaved forests where high levels of light are reduced in summer, and cold temperatures in winter are insulated by mulched layers of fallen leaves.

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Examining the factors influencing leaf disease intensity of Kalopanax septemlobus (Thunb. ex Murray) Koidzumi (Araliaceae) over multiple spatial scales: from the individual, forest stand, to the regions in the Japanese Archipelago

  • Sakaguchi, Shota;Yamasaki, Michimasa;Tanaka, Chihiro;Isagi, Yuji
    • Journal of Ecology and Environment
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    • v.35 no.4
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    • pp.359-365
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    • 2012
  • We investigated leaf disease intensity of Kalopanax septemlobus (prickly castor oil tree) caused by the parasitic fungus Mycosphaerella acanthopanacis, in thirty natural host populations in the Japanese Archipelago. The disease intensity observed for individual trees were analyzed using a generalized additive model as a function of tree size, tree density, climatic terms and spatial trend surface. Individual tree size and conspecific tree density were shown to have significant negative and positive effects on disease intensity, respectively. The findings suggest that the probability of disease infection is partly determined by dispersal of infection agents (ascospores) from the fallen leaves on the ground, which can be enhanced by aggregation of host trees in a forest stand. Regional-scale spatial bias was also present in disease intensity; the populations in northern Japan and southern Kyushu were more severely infected by the fungus than those in southwestern Honshu and Shikoku. Regional variation of disease intensity was explained by both climatic factors and a trend surface term, with a latitudinal cline detected, which increases towards the north. Further research should be conducted in order to understand all of the factors generating the latitudinal cline detected in this study.

Property Changes of Vertical Soil Layers Planted with Zelkova serrata(Thunberg) Makino on the Reclaimed Land from the Sea in the Gwangyang Bay, Korea (광양만 임해 매립지 느티나무 식재지 토양의 수직적 특성 변화)

  • Kim Do-Gyun;Kim Yong-Shik
    • Journal of the Korean Institute of Landscape Architecture
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    • v.33 no.2 s.109
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    • pp.60-70
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    • 2005
  • This study was carried out to elucidate the vertical characteristics of soil properties at six planted sites of land reclaimed from the sea, in Gwangyang Bay, Jeollanam-do Province, Korea. Based on the types of planting site, the chemical properties of the vertical soil layers varied. The vertical variation was great in the planting sites $Z_1\;and\;Z_2$, but less varied in the mounded planting sites $Z_3,\;Z_5,\;and\;Z_6$. Major reasons for the vertical variation in soil chemical properties included differences in the accumulation of organic matter, soil disturbance by heavy construction equipment, and heterogeneity of soil properties between soil horizons. As soil depths increased, soil salts varied. The electrical conductivity (ECe) increased in the lower areas of planting sites $Z_1\;and\;Z_2$, and the disturbed, saline planting site $Z_3$, but decreased in the lower areas of $Z_3,\;Z_5,\;and\;Z_6$. These tendencies did not coincided with exchange cation concentrations $(Na^+,\;K^+,\;Mg^{++},\;Ca^{++})$. Both total carbon (T-C) and total nitrogen (T-N) accumulated more in the lower areas of planting sites than in the higher areas, and levels were higher closer to the surface than in the soil depths. It is supposed that these tendencies are related to the accumulation of fallen leaves or other organic matter at the soil surface, and the soil chemicals then slowly move downward from the surface. Impediments to tree growth included soil hardiness, high soil salinity and exchangeable cation concentration, low soil moisture content, acidic or alkaline soil, low organic matter, heterogeneity of soil texture and establishment of soil stratification.

Analysis of Use Disposition and Consciousness about Children′s Playground management by Residents (지역주민의 아동공원 이용성 및 관리에 대한 의식분석)

  • 이기철;김동필
    • Journal of the Korean Institute of Landscape Architecture
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    • v.17 no.2
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    • pp.15-25
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    • 1989
  • The purpose of this study was to supply data of resident′s participation direction about children′s playground management. In this study, use disposition and consciousness of resident about management are investigated and analyzed at the 5 children′s playground in Taegu city. The results of this study were as follows: The result of resident′s use disposition showed ; visiting frequency was "everyday or occasionally(53.5% )", and visiting purpose was "for children(47.9 %), for rest, sports, spare time(24.6%)" and visiting time was equal1y except forenoon, and staying time was "within 1 hour(73.1%)". The satisfaction about park facilities and park existence of residents′ is composed importance degree of which is convenient, manyfunction spaces, managemental of tree and facilities in order. 9.3% of residents were proposal experience about management, and concern ratio of circumferenmce showed highly "concerned answer(45.9%)" About consciousness ratio of management subject, 46.5% of residents depended on authorities leading. Wholly, recognition ratio showed low. Park administration of authorities leading and lack of resident′s concern wore thought as its problem. About experience of cleaning beautification rout children′s playground, 14.2% of residents answered "be experience". Participation type of desirous management showed highest "cleaning of fallen leaves and rubbish(22.7% )". So, residents wished to take part in such simple managements. Charge of necessary tool and cost for management showed highest "partial charge of residents (47.9% )". About participant ratio of self government activity made by residents, 75.1% of residents answered "don′t be participated". A reason of nonparticipation showed "insufficiency of place and opportunity (38.7%), deficiency of time(17.97)". Activity of initiative and existing group can be done as a fine device in future. Desirous events for children and residents showed highest "play guidence for children or meeting for aged milan(40.7% )". Therefore, it will have to consider enough about resident′s participation program for activity of use and efficient management of children′s playground.

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Observation on the Fauna of Arthropods form Apple Orchards in Winter in Kyongbuk Province (경북지방 사과원의 동계 절지동물(Arthropoda)상)

  • 이영인;권기면;이순원;류하경;류언하
    • Korean journal of applied entomology
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    • v.36 no.3
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    • pp.231-236
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    • 1997
  • Arthropods of 3 Classes, 19 Orders and 58 Families were collected by the enticing band from the trunk of apple trees in winter in Kyongbuk province. The two spotted spider mite, Tetranychu.v urricae Koch, was dominant species with 53.0%, followed by Eriosomtr lanigerutn Hausmann. 16.7%. Oribatida 13.3% and Collembola 9.3%. Of those, herbivores were majority, followed by some decomposers and few natural enemies. Arthropods of 2 Classes, 12 Orders and 17 Families were observed from the fallen leaves. T. urric,ae 63.1% was dominant, followed by Collembola 13.797~ and other Arthropods. While 2 Classes, 9 Orders and 18 Families were investigated from the soil of apple orchards. They were collembola 37.9%. Oribatida 34.476, T. urticae Ih.l% and others in few numbers. Decomposers were majority, followed by herbivores and few natural enemies.

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A Numerical Study of Flame Spread of A Surface Forest Fire (지표화 산불의 화염전파 수치해석)

  • Kim, Dong-Hyun;Lee, Myung-Bo;Kim, Kwang-Il
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.80-83
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    • 2008
  • The characteristics of the spread of a forest fire are generally related to the attributes of combustibles, geographical features, and meteorological conditions, such as wind conditions. The most common methodology used to create a prediction model for the spread of forest fires, based on the numerical analysis of the development stages of a forest fire, is an analysis of heat energy transmission by the stage of heat transmission. When a forest fire breaks out, the analysis of the transmission velocity of heat energy is quantifiable by the spread velocity of flame movement through a physical and chemical analysis at every stage of the fire development from flame production and heat transmission to its termination. In this study, the formula used for the 1-dimensional surface forest fire behavior prediction model, derived from a numerical analysis of the surface flame spread rate of solid combustibles, is introduced. The formula for the 1-dimensional surface forest fire behavior prediction model is the estimated equation of the flame spread velocity, depending on the condition of wind velocity on the ground. Experimental and theoretical equations on flame duration, flame height, flame temperature, ignition temperature of surface fuels, etc., has been applied to the device of this formula. As a result of a comparison between the ROS(rate of spread) from this formula and ROSs from various equations of other models or experimental values, a trend suggesting an increasing curved line of the exponent function under 3m/s or less wind velocity condition was identified. As a result of a comparison between experimental values and numerically analyzed values for fallen pine tree leaves, the flame spread velocity reveals has a error of less than 20%.

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