• Title/Summary/Keyword: subterranean

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Effects of Sward Composition and N.P Fertilization on Forage Yields and Intercompetition of Subterranean clover-Italian Ryegrass and Berseem clover-Italian Ryehrass Mixtures (식생비율과 질소.인산시용이 Subterranean Clover-Italian Ryegrass 및 Berseem Clover-Italian Ryegrass 혼파 초지의 생산성과 종간경합에 미치는 영향)

  • 강진호
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.37 no.3
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    • pp.274-282
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    • 1992
  • Annual forage crops have been increasingly important for conpensating insufficient forage production of perennial pastures took place for short interval. This experiment was conducted to determine the effect of sward composition and NㆍP fertilization on forage production and intercompetition of subterranean clover-Italian ryegrass and berseem clover-Italian ryegrass. The two clovers were grown in the field at the clover/ryegrass ratios of 0/100, 25/75, 50/50, 75/25 and 100/0 where no, N (200 kg /ha), P (50 kg /ha) or NㆍP fertilization was done. Each crop was separated after harvest and drying. Relative Crowding Coefficient (RCC), aggressivity and Relative Yield Total (RYT) were analyzed on the basis of the harvested dry matter of each crop. Berseem clover-ryegrass mixtures produced greater yield than subclover-ryegrass mixtures as a result of higher yields of the two component species. In the former forage yield was increased with increased rate of clover up to 75%, while in the latter the highest yields were obtained at more than 50% of the clover. In the mixtures N stimulated the growth of ryegrass, whereas P did only that of subclover. The two clovers produced more forage than the companion grass under no and only P fertilization although the reverse result was true under N or NㆍP fertilization, but the annual forage yield was decreased in the order of N and P, N, P, and no fertilization. The mixture yields were overyielded compared to the Expected Yield. Although generally RCCs and RYTs of subclover were higher than those of berseem clover in the mixtures differing the composition rate or under no and only P fertilization, those of the former clover were lower under N or NㆍP fertilization. In the clover-ryegrass mixtures, ryegrass acted as an aggressor and became more aggressive under P fertilization.

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Characteristic of Termite inhabits in South Korea and the control (한국 서식 흰개미의 특성과 방제)

  • Han, Sung-Hee;Lee, Kyu-Shik;Chung, Young-Jae
    • 보존과학연구
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    • s.19
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    • pp.133-158
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    • 1998
  • There are about 2,000 species of termite in the World, but one species of termite inhabits in the southern part of Korean peninsula. Termites are social insects that live in colonies. The colonies are composed of king, queen, soldiers and workers. Termite food consists of cellulose obtained from wood. Protozoa in their digestive tracts convert the cellulose into usable food. Korean termite is a subspecies of Reticulitermes speratus Kolbe, Rhinotermitidae. It's subterranean termite and the scientic name is R. speratus kyushensis Morimoto. The subterranean termite must nest in the soil in order to survival, and infest soft-wood which contact with the soil near the nest. There are several ways which subterranean termite infestations can be noticed. Atcertain times of the year during daylight hours, king and queen termites emerge from the colonies. The propose of these flight is to establish new colonies. The termite is a decomposer of biological ecosystem, but an invader in the preservation of cultural properties as like wood buildings. There are serveral control methods for the prevention of wood building from termite's damages. Those are biological control, ecological control, physical control and chemical control. Ecological and Physical control are the best methods in the new constructing wood-building. Fumigation which is a method of chemical control, is the best method for the building damaged by the termite. After the fumigation, we have totake wood & soil treatments for the building and nearby in order not to be reinvaded by the termites.

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Anti-termite Activity of Tamanu Bark Extract (Calophyllum inophyllum L.)

  • Ainun ZALSABILA;Wasrin SYAFII;Trisna PRIADI;SYAHIDAH
    • Journal of the Korean Wood Science and Technology
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    • v.52 no.2
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    • pp.134-144
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    • 2024
  • This study aimed to analyze the anti-termite properties of tamanu (Calophyllum inophyllum L.) stem bark extracts against subterranean termites, specifically, Coptotermes curvignathus. The bark powder of C. inophyllum was extracted using different solvents, such as n-hexane, ethyl acetate, and methanol, using the maceration method. Anti-termite testing was performed using two paper disc methods: no- and two-choice tests. Whatman test paper was dripped with the extract solutions at concentrations of 4%, 6%, 8%, and 10% (w/v). Subsequently, the treated paper disc was placed into an acrylic tube, and the subterranean termite was added. The parameters utilized in the test included termite mortality and the weight loss of the test paper. The results revealed that the total extract yield of C. inophyllum stem bark was 30.24%. Furthermore, the extractive substances from C. inophyllum bark exhibited anti-termite activity. The most favorable outcomes were obtained with the n-hexane and ethyl acetate extracts at a concentration of 10%. The termite mortality and weight loss of the test paper were respectively 66% and 5.67% for the n-hexane extract and 66.67% and 6.19% for the ethyl acetate extract. In addition, the n-hexane extract contained friedelan-3-one, while the ethyl acetate extract contained 1,2-benzene dicarboxylic acid, dinonyl ester, and friedelan-3-one. The results suggested that these compounds are responsible for the observed anti-termite activity.

Biomass, Net Production and Nutrient Distribution of Bamboo Phyllostachys Stands in Korea (왕대속(屬) 대나무림(林)의 물질생산(物質生産) 및 무기영양물(無機營養物) 분배(分配)에 관한 연구(硏究))

  • Park, In Hyeop;Ryu, Suk Bong
    • Journal of Korean Society of Forest Science
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    • v.85 no.3
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    • pp.453-461
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    • 1996
  • Three Phyllostachys stands of P. pubescens, P. bambusoides and P. nigra var, henonis in Sunchon were studied to investigate biomass, net production and nutrient distribution. Five $10m{\times}10m$ quadrats were set up and 20 sample culms of 2 years and over were harvested for dimension analysis in each stand. One year old culms and subterranean parts were estimated by the harvested quadrat method. The largest mean DBH, height and basal area were shown in P. pubescens stand, and followed by P. nigra var. henonis stand and P. bambusoides stand. There was little difference in accuracy among three allometric biomass regression models of logWt=A+B1ogD, $logWt=A+BlogD^2H$ and logWt=A+BlogD+ClogH, where Wt, D and H were dry weight, DBH and height, respectively. Analysis of covariance showed that there were significant differences in intercept among the linear allometric biomass regressons of three Phyllostachys species. Biomass included subterranean parts was the largest in P. pubescens stand(103.621t/ha), and followed by P. nigra var. henonis stand(86.447t/ha) and P. bambusoides stand(36.767t/ha). Leaf biomass was 6.3% to 7.8% of total biomass in each stands. The ratio of aboveground biomass and subterranean biomass in each stand was 1.87 to 2.26. Net production included subterranean parts was the greatest in P. pubescens stand(6.115t/ha/yr), and followed by P. nigra var. henonis stand(5.609t/ha/yr) and P, bambusoides stand(3.252t/ha/yr). The highest net assimilation ratio was estimated in P. pubescens stand(2.979), and followed by P. nigra var. henonis stand(2.752) and P. bambusoides stand(2.187). Biomass accumulation ratio of each stand was 2.679 to 5.358. Concentrations of N, P and Mg were the highest in leaves, and followed by subterranean parts, and culms+branches in all three species. Concentration of Ca was the highest in leaves, and followed by culms+branches, and subterranean parts in all three species. The difference in biomass among three species stands was caused by their culm size, leaf biomass, net assimilation ratio, and efficiency of leaves to produce culms.

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Channel Migration of Byeongmun River Caused by Roof Collapse of Gurin Cave in Mount Halla, Jeiu Island (한라산 구린굴의 천장 함몰로 인한 병문천의 유로 변경)

  • Kim, Tae-Ho;An, Jong-Gi
    • Journal of the Korean Geographical Society
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    • v.43 no.4
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    • pp.466-476
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    • 2008
  • Gurin Cave, 442 m long, is a lava tube developed on the northern slope of Mount Halla. Seventy-three meters of its lower reach became a river channel since Byeongmun River flowed into a window after roof collapse took place. The subterranean channel has a width of 447 cm and a height of 501 cm, respectively. Its banks show well-developed lava shelves of a typical lava tube, while its floor has sculpted forms which characterize a bed of a bedrock stream. The reach is likely to be collapsed and then has four collapsed windows since its roof has the densely developed testudinal joints and consists of thin lavas with a thickness of 30 to 60 cm. Before the subterranean channel appeared, a ground channel flowed over the cave and joined into a main channel of Byeongmun River at 653 m in altitude. However, the subterranean channel substituted the ground channel since a bed of the ground channel collapsed into the cave. The new channel, flowing through the cave, joined into a main channel at 660 m in altitude. As the drainage area of Byeongmun River expanded upstream the cave, the new channel changed into a main channel. Since floodwater flows down the ground channel as well as the subterranean channel, a distributary stream has temporarily appeared at the collapsed window. Lava tubes are likely to have an affect on the development of river system in Jeiu Island, in that the caves have constantly shown roof-fall.

MODULATION OF ANTIMUTAGENIC RESPONSE DETECTED IN AFRICAN BAMBARA GROUNDNUT

  • Mossanda, K.S.A;Kingigila, M.D.
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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    • pp.103-104
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    • 2001
  • Introduction: Bambara groundnut (Vigna subterranean) commonly eaten in Central and Southern Africa region where the incidence of gastric and liver cancer is high because of the consumption of contaminated food by mycotoxins, has been investigated for antitumorigenic activitly using the classical Ames test with some modifications.(omitted)

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Establishment by Seeds and Maintenance by Ramets in Elaeagnus umbellate Population (한국산 보리수나무 개체군의 종자에 의한 정착과 라메트에 의한 유지)

  • You, Young-Han;Kim, Kyung-Bunm;An, Chung-sun;Kim, Joon-Ho;Song, Seung-Dal
    • The Korean Journal of Ecology
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    • v.17 no.2
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    • pp.203-211
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    • 1994
  • The establishment by seeds and the maintenance by ramets of the autumn olive (Elaeagnus umbellata) population were investigated in the Namhansansung Provincial Park, Jungbu-myun, Kwangju-gun, Kyunggi-do. Seed production and germination rate were 3, 300 $seeds{\cdot}m^{-2}{\cdot}yr^{-1}$ and 52%, respectively. The ramet formation in the population was classified into 4 types: stump type, creeping root type, lateral root type and secondary creeping root type. The subterranean creeping roots were 0.1~1.0 m in length, 4.5~14.0 mm in diameter and 0.06~0.2 m in soil depth. The number of ramets formed from a node was 1~21. The subterranean roots spread $5~509cm^2{\cdot}plant^{-1}{\cdot}yr^{-1}$, which began to be produced from 7~9 year-old individuals. The number of stems was 1~67 per stump, which was reduced by self-thinning from 2 to 14 year-old trees. The frequency distribution of stem diameter$(D_{30})$ showed a reverse J-shaped curve, suggesting that this population be maintained perpetually by their own ramets.

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The Structures of Two Diosgenin Glycosides Isolated from the Subterranean Parts of Allium fistuiosum (파 지하부로부터 분리된 2종의 Diosgenin 배당체의 구조)

  • Jung, Keun-Young;Do, Jae-Chul;Son, Kun-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.22 no.3
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    • pp.313-316
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    • 1993
  • The structures of dioscin(1) and saponin P-d(2), isolated from the subterranean part of Allium fistulosum, were determined as diosgenin 3-O-$\alpha$-L-rhamnopyranosyl (1longrightarrow2)-[$\alpha$-L-rhamnopyranosyl (1longrightarrow4)]-$\beta$-D-glucopyranoside (1, ) and diosgenin 3-O-$\alpha$-L-rhamnopyranosyl (1longrightarrow4)-$\alpha$-L-rhamnopyranosyl(1longrightarrow4)[$\alpha$-L-rhamno-pyranosyl (1longrightarrow2)]-$\beta$-D-glucopyranoside (2) by spectroscopic and chemical degradational methods. The prosa-pogenin(4), which was provided on partial hydrolysis of 2, was not reported in previous literature.

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