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Chemical Fluxes at the Sediment-Water Interface Below Marine Fish Cages on the Coastal Waters off Tong-Young, South Coast of Korea (남해안 통영지역 가두리양식장 해수-퇴적물 경계면에서의 chemical fluxes)

  • Shim, Jeong-Hee;Kang, Young-Chul;Choi, Jin-Woo
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.2 no.2
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    • pp.151-159
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    • 1997
  • Benthic respiration and chemical fluxes were measured at the sediment-water interface underlying the marine fish cages floating on the open coastal waters off Tong-Young, the South Coast of Korea. The effects of cage farming on coastal benthic environment and on mass balance of organic carbon in the benthic boundary layer under the marine fish cages are addressed. In a growing season of caged fishes of June, 1995, benthic chambers and sediment traps were deployed on the sediment-water interfaces of the two sites chosen for this study: 1) Cage Site, directly underlying the fish cages of the farm at 18 m water depth, and 2) Control Site, about 100 m away from the farm at 32 m water depth. Benthic respiration rates and chemical fluxes were calculated from the evolution of dissolved oxygen and chemicals in the chamber water, and mass balance of organic carbon in the benthic boundary layer was constructed based on the vertical flux of particulate organic matter (POM) and chemical fluxes out of the sediment. High organic dumping (6400 mg C $m^{-2}d^{-1}$) and high benthic respiration (230 mmol $O_2\;m^{-2}d^{-1}$) were observed at the Cage Site. Equivalent to 40% of vertical flux of organic carbon into the Cage Site seemed to be decomposed concurrently and released back to overlying waters (2400 mg C $m^{-2}d^{-1}$). Consequently, up to 4000 mg C $m^{-2}d^{-1}$ of organic carbon could be buried into the farm sediment (equivalent to 60% of organic carbon flux into the Cage Site). At the Control Site, relatively less input of organic carbon (4000 mg C $m^{-2}d^{-1}$) and low benthic respiration rate (75 mmol $O_2\;m^{-2}d^{-1}$) were observed despite short distance away from the cages. The influence of cage farming on benthic chemical fluxes might be restricted and concentrated in the sea bottom just below the fish cages in spite of massive organic dumping and high current regime around the fish cage farm.

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Effect of Trichostatin A on Anti HepG2 Liver Carcinoma Cells: Inhibition of HDAC Activity and Activation of Wnt/β-Catenin Signaling

  • Shi, Qing-Qiang;Zuo, Guo-Wei;Feng, Zi-Qiang;Zhao, Lv-Cui;Luo, Lian;You, Zhi-Mei;Li, Dang-Yang;Xia, Jing;Li, Jing;Chen, Di-Long
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.18
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    • pp.7849-7855
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    • 2014
  • Purpose: To investigate the effect of deacetylase inhibitory trichostatin A (TSA) on anti HepG2 liver carcinoma cells and explore the underlying mechanisms. Materials and Methods: HepG2 cells exposed to different concentrations of TSA for 24, 48, or 72h were examined for cell growth inhibition using CCK8, changes in cell cycle distribution with flow cytometry, cell apoptosis with annexin V-FTIC/PI double staining, and cell morphology changes under an inverted microscope. Expression of ${\beta}$-catenin, HDAC1, HDAC3, H3K9, CyclinD1 and Bax proteins was tested by Western blotting. Gene expression for ${\beta}$-catenin, HDAC1and HDAC3 was tested by q-PCR. ${\beta}$-catenin and H3K9 proteins were also tested by immunofluorescence. Activity of Renilla luciferase (pTCF/LEF-luc) was assessed using the Luciferase Reporter Assay system reagent. The activity of total HDACs was detected with a HDACs colorimetric kit. Results: Exposure to TSA caused significant dose-and time-dependent inhibition of HepG2 cell proliferation (p<0.05) and resulted in increased cell percentages in G0/G1 and G2/M phases and decrease in the S phase. The apoptotic index in the control group was $6.22{\pm}0.25%$, which increased to $7.17{\pm}0.20%$ and $18.1{\pm}0.42%$ in the treatment group. Exposure to 250 and 500nmol/L TSA also caused cell morphology changes with numerous floating cells. Expression of ${\beta}$-catenin, H3K9and Bax proteins was significantly increased, expression levels of CyclinD1, HDAC1, HDAC3 were decreased. Expression of ${\beta}$-catenin at the genetic level was significantly increased, with no significant difference in HDAC1and HDAC3 genes. In the cytoplasm, expression of ${\beta}$-catenin fluorescence protein was not obvious changed and in the nucleus, small amounts of green fluorescence were observed. H3K9 fluorescence protein were increased. Expression levels of the transcription factor TCF werealso increased in HepG2 cells following induction by TSA, whikle the activity of total HDACs was decreased. Conclusions: TSA inhibits HDAC activity, promotes histone acetylation, and activates Wnt/${\beta}$-catenin signaling to inhibit proliferation of HepG2 cell, arrest cell cycling and induce apoptosis.

Water Quality Variation and Biotic Community Characteristics in Juam Lake (2011) (주암호의 수질 변동 및 생물군집 특성(2011))

  • Song, Hyo-Jeong;Hwang, Kyung-Sub;Park, Jong-Hwan;Lee, Hak-Young;Kim, Jong-Sun;Kim, Hyun-Woo;Lim, Dong-Ok;Lee, Sung-Hwi;Lim, Byung-Jin
    • Korean Journal of Environmental Biology
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    • v.31 no.1
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    • pp.37-44
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    • 2013
  • This study was to investigate water quality and biotic community characteristics in Juam Lake. In water quality, water temperatures was $3.8{\sim}21.2^{\circ}C$, 6.7~8.6 in pH, $64{\sim}76{\mu}s\;cm^{-1}$ in Conductivity, $5.3{\sim}13.2mg\;L^{-1}$ in DO, $2.5{\sim}3.3mg\;L^{-1}$ in COD, $1.0{\sim}5.1mg\;L^{-1}$ in SS, $0.622{\sim}0.841mg\;L^{-1}$ in T-N, $0.007{\sim}0.019mg\;L^{-1}$ in T-P and $2.8{\sim}8.8mg\;m^{-3}$ in Chl-a. Revised Carlson's Index (TSIm) assessment using total phosphorus (TP) and chlorophyll-a domonstrated that the trophic states of Juam Lake were rated as mesotrophic. A total of 53 species of phytoplankton were identified. They were 28 Bacillariophyceae, 13 Chlorophyceae, 3 Cyanophyceae, and 9 Other algal taxa. The standing crops of phytoplankton was ranged from $113cells\;mL^{-1}$ to $2,909cells\;mL^{-1}$. A total of 16 species of zooplankton were identified (10 rotifers, 4 cladocerans and 2 copepods). Total zooplankton abundance was $309ind.\;L^{-1}$ to $435ind.\;L^{-1}$. The collected benthic macroinvertebrates from the surveyed sites in Juam Lake were 1,038 individuals, 33 species, 21 families and 12 orders. A dominant species was Uracanthella rufa and a subdominant species was Ecdyonurus kibunensis. Hydrophytes recorded from Juam Lake were identified 9 taxa. Emerged plants, floating plants among the hydrophytes was classified 8, 1 taxa, respectively. Ecosystem disturbance wildplant by Environment Ministry found were Paspalum distichum var. distichum and Ambrosia artemisiaefolia. A total of 30 species (6 families) were collected fishs from Juam Lake. There were 10 Korean endemic species (33.3% of collected species number) and 3 exotic species (10.0%).

International Monetary System Reform and the G20 (국제통화제도의 개혁과 G20)

  • Cho, Yoon Je
    • KDI Journal of Economic Policy
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    • v.32 no.4
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    • pp.153-195
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    • 2010
  • The recent global financial crisis has been the outcome of, among other things, the mismatch between institutions and the reality of the market in the current global financial system. The International financial institutions (IFIs) that were designed more than 60 years ago can no longer effectively meet the challenges posed by the current global economy. While the global financial market has become integrated like a single market, there is no international lender of last resort or global regulatory body. There also has been a rapid shift in the weight of economic power. The share of the Group of 7 (G7) countries in global gross domestic product (GDP) fell and the share of emerging market economies increased rapidly. Therefore, the tasks facing us today are: (i) to reform the IFIs -mandate, resources, management, and governance structure; (ii) to reform the system such as the international monetary system (IMS), and regulatory framework of the global financial system; and (iii) to reform global economic governance. The main focus of this paper will be the IMS reform and the role of the Group of Twenty (G20) summit meetings. The current IMS problems can be summarized as follows. First, the demand for foreign reserve accumulation has been increasing despite the movement from fixed exchange rate regimes to floating rate regimes some 40 years ago. Second, this increasing demand for foreign reserves has been concentrated in US dollar assets, especially public securities. Third, as the IMS relies too heavily on the supply of currency issued by a center country (the US), it gives an exorbitant privilege to this country, which can issue Treasury bills at the lowest possible interest rate in the international capital market. Fourth, as a related problem, the global financial system depends too heavily on the center country's ability to maintain the stability of the value of its currency and strength of its own financial system. Fifth, international capital flows have been distorted in the current IMS, from EMEs and developing countries where the productivity of capital investment is higher, to advanced economies, especially the US, where the return to capital investment is lower. Given these problems, there have been various proposals to reform the current IMS. They can be grouped into two: demand-side and supply-side reform. The key in the former is how to reduce the widespread strong demand for foreign reserve holdings among EMEs. There have been several proposals to reduce the self-insurance motivation. They include third-party insurance and the expansion of the opportunity to borrow from a global and regional reserve pool, or access to global lender of last resort (or something similar). However, the first option would be too costly. That leads us to the second option - building a stronger globalfinancial safety net. Discussions on supply-side reform of the IMS focus on how to diversify the supply of international reserve currency. The proposals include moving to a multiple currency system; increased allocation and wider use of special drawing rights (SDR); and creating a new global reserve currency. A key question is whether diversification should be encouraged among suitable existing currencies, or if it should be sought more with global reserve assets, acting as a complement or even substitute to existing ones. Each proposal has its pros and cons; they also face trade-offs between desirability and political feasibility. The transition would require close collaboration among the major players. This should include efforts at the least to strengthen policy coordination and collaboration among the major economies, and to reform the IMF to make it a more effective institution for bilateral and multilateral surveillance and as an international lender of last resort. The success on both fronts depends heavily on global economic governance reform and the role of the G20. The challenge is how to make the G20 effective. Without institutional innovations within the G20, there is a high risk that its summits will follow the path of previous summit meetings, such as G7/G8.

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An Area-Efficient Time-Shared 10b DAC for AMOLED Column Driver IC Applications (AMOLED 컬럼 구동회로 응용을 위한 시분할 기법 기반의 면적 효율적인 10b DAC)

  • Kim, Won-Kang;An, Tai-Ji;Lee, Seung-Hoon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.53 no.5
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    • pp.87-97
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    • 2016
  • This work proposes a time-shared 10b DAC based on a two-step resistor string to minimize the effective area of a DAC channel for driving each AMOLED display column. The proposed DAC shows a lower effective DAC area per unit column driver and a faster conversion speed than the conventional DACs by employing a time-shared DEMUX and a ROM-based two-step decoder of 6b and 4b in the first and second resistor string. In the second-stage 4b floating resistor string, a simple current source rather than a unity-gain buffer decreases the loading effect and chip area of a DAC channel and eliminates offset mismatch between channels caused by buffer amplifiers. The proposed 1-to-24 DEMUX enables a single DAC channel to drive 24 columns sequentially with a single-phase clock and a 5b binary counter. A 0.9pF sampling capacitor and a small-sized source follower in the input stage of each column-driving buffer amplifier decrease the effect due to channel charge injection and improve the output settling accuracy of the buffer amplifier while using the top-plate sampling scheme in the proposed DAC. The proposed DAC in a $0.18{\mu}m$ CMOS shows a signal settling time of 62.5ns during code transitions from '$000_{16}$' to '$3FF_{16}$'. The prototype DAC occupies a unit channel area of $0.058mm^2$ and an effective unit channel area of $0.002mm^2$ while consuming 6.08mW with analog and digital power supplies of 3.3V and 1.8V, respectively.

Studies on Application Method and Safety of Macrogranule(GG) Herbicide for Remote-controlled Aerial Application (무인헬기용 Macrogranule(GG) 제초제의 안정성 및 살포방법 연구)

  • Yoon, Cheol-Su;Bae, Chang-Hyu;Lee, Sheong-Chun;Kim, Kyung-Hyun;Lee, Kye-Hwan;Cho, Tae-Kyoung;Hwang, In-Cheon
    • Korean Journal of Weed Science
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    • v.31 no.3
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    • pp.294-307
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    • 2011
  • This experiment carried out to confirm characteristics of macrogranule (GG) for herbicidal efficacy by using remote-controlled aerial application (RCAA) to control annual and perennial weeds in rice paddy field, application methods, and application times of formulation types. Particle of 500 g GG having average diameter of 2.5~3 mm was over 85 percent, the bulk density of the particle was $0.2\sim0.4g\;mL^{-1}$ and the particle was water floating granule. Active ingredients and external form of halosulfuronmethyl+mefenacet GG remained stable under condition of storage stability test. The disintegration time of the GG was faster as the water temperature was increased. But disintegration time was not affected by pH on the water conditions. By using hand, spoon and power applicator, drift distances of GG were 4~5m, 7 m and 10~12 m, respectively. GG showed good herbicidal efficacy and plant safety in all of the application methods such as, using hand, spoon, power applicator and RCAA. Application times of GG, GR, SC and TB by hand in $4,000m^2$ were 38 min. 4 sec, 42 min. 20 sec, 38 min. 10 sec and 21 min. 4 sec, respectively, but application time of GG by using RCAA was 1 min 32 sec. According to appearance and characteristics of formulation types, suspension concentrate (SC) and GG were possible formulation types for RCAA.

study of comparison between Nae-gyung(內經) and later physian's theory on In-yeong-gi-go Maek(人迎氣口脈) (인영기구맥(人迎氣口脈)에 대(對)한 내경(內經)과 후대(後代) 의가설(醫家說)과의 비교(比較) 연구(硏究))

  • Kim, Tae-Eun;Kim, Tai-Hee
    • The Journal of Internal Korean Medicine
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    • v.15 no.1
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    • pp.152-164
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    • 1994
  • In Nai-Gyung(內經), it is said that In-Yeong(人迎) means In- Yeong Maek(人迎脈), Gi-Gu m- eans Tson-Gu(寸口) or Maek- Gu(脈口), In-yeong, artery in the side of neck, is located before Yeong-Geun(瓔筋), called as Jok-Yang-Myung-Maek(足陽明脈),so the part of In-Yeong-Maek means In-Yeong-Hyul(人迎穴) of Jok-Yang-Myung- Wi-Gyung(足陽明胃經) showing the artery in the side of neck. The part of Tson-Gu-Maek is that of artery in Yo-Gol(橈骨), beating source of Soo-Tae-Eum-Maek (手太陰脈) Of In-Yeong-Gi-Gu-Maek, In-Yeong-Maek mainly consists of Yang(陽), Gi-Gu-Maek of Eum(陰), so In-Yeung means physical disease, short of extra Eum component. They said that if In-Yeong-Maek was more than Gi-Gu-Maek, it meant physical injury, while Gi-Gu-Maek was more than In- Yeo-ng-Maek, it meant internal injury. In-Yeong-Gi-Gu-Maek is the one to distinguish the external and internal, the inside and outside, Eum and Yang, but there is no definite classification method to distinguish it, also it is difficult to grasp the comparison of 1sung(1盛), 2sung(2盛), 3sung(3盛), interrelation with 12-Gyung-Rak(l2經絡), change of maek phases, so necessary to set up the clear definition for In-Yeong-Gi-Gu-Maek. For the two theories as to In-Yeong-Gi-Gu-Maek according to Nai-Gyung, the one is to diagnose the maek by comparing the In-Yeong-Hyul with Tson-Gu of Soo-Tae-Eum-Maek as Gi-Gu in the both sides of neck part, he other is to divide the left and right of Gi-Gu-Maek in to In-Yeong and Gi-Gu afterwards, but today it is difficult to compare and explain the medical theory afterwards owing to insufficient consideration of In-Yeong-Gi-Gu-Maek at Nai-Gyung. The diagnosis of In-Yeong-Gi-Gu-Maek at Nai-Gyung to distinguish the surplus and shortage of Eum and Yang up to now since Nai-Gyung has so important and diagnostic value as to grasp the exact meaning. Herewith, this researcher com-pared Nai-Gyung and medical theory afterwards, reported it to consider the fixed position and changing process of viscera and entrails arrangement of literatures introducing In-Yeong-Gi-Gu-Maek, examining the change of maek phases for normal maek and a-bnormal maek of In-Yeong-Gi-Gu-Maek, considering the 1 sung, 2 sung, 3 sung maek phases in In-Yeong-Gi- Gu-Maek. According to the above results, the conclusion was reached as follows. 1. In-Yeong as the outside indicates external disease(外感), showing the surplus and shortage of Yang symptom by having Boo-Maek(浮脈) as Py-ung-Maek(平脈), Gi-Gu as the inside indicates internal disease(內傷), showing the surplus and shortage of Eum symptom by having Chim-Maek(沈脈) as P-yung-Maek(平脈). 2. In Pyung-Maek of In- Yeong-Maek as Boo-Maek, g-radual sinking of more floated changing maek because of disease means the improvement of di-sease, in Pyung-Maek of Gi- Gu-Maek as Chim- Maek, gradual floating of more sunken changing maek because of disease means the improvement of disease. 3. They said that disease of Jok-Gyung-Rak(足經絡) is cha-nged to that of Soo-Kyung-Rak(手經絡) when Jo-Maek(躁脈) appears whether In-Yeong-Maek or Gi-Gu-Maek 4. With the exemples of 1 sung 2 sung 3 sung it was porned with the relation of Pyo-Ri-Soo-Jok(表裏手足). Therfore I can guess that this fact is a moment explained the Bu-You-Sa-Kyung(部有四經) mentioned in Nan-Gyung-18-Nan(難經 第18難). 5. I think that In-Yeong and Gi-Gu, as a diagnosis method which distinguish between the inside indicates internal disease and the outside indicates external disease, is required to study further researches.

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Optimization Test of Plant-Mineral Composites to Control Nuisance Phytoplankton Aggregates in Eutrophic Reservoir (부영양 저수지의 조류제거를 위한 기능성 천연물질혼합제의 최적화 연구)

  • Lee, Ju-Hwan;Kim, Baik-Ho;Moon, Byeong-Cheon;Hwang, Soon-Jin
    • Korean Journal of Ecology and Environment
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    • v.44 no.1
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    • pp.31-41
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    • 2011
  • To optimize the natural chemical agents against nuisance phytoplankton, we examined algal removal activity (ABA) of Plant-Mineral Composite (PMC), which already developed by our teams (Kim et al., 2010), on various conditions. The PMC are consisted of extracted-mixtures with indigenous plants (Camellia sinensis, Quercusacutissima and Castanea crenata) and minerals (Loess, Quartz porphyry, and natural zeolite), and characterized by coagulation and floating of low-density suspended solids. A simple extraction process was adopted, such as drying and grinding of raw material, water-extraction by high temperature-sonication and filtering. All tests were performed in 3 L plastic chambers varying conditions; six different concentrations ($0{\sim}1.0\;mL\;L^{-1}$), six light intensities ($8{\sim}1,400\;{\mu}mol\;m^{-2}s^{-1}$), three temperatures ($10{\sim}30^{\circ}C$), four pHs (7~10), five water depths (10~50 cm), and three different waters dominated by cyanobacteria, diatom, and green algae, respectively. Results indicate that the highest ABA of PMC was seen at $0.05\;mL\;L^{-1}$ in treatment concentrations, where showed a reduction of more than 80% of control phytoplankton biomass, while $1,400\;{\mu}mol\;m^{-2}s^{-1}$ in light intensity (>90%), $20{\sim}30^{\circ}C$ temperature (>60%), 7~9 in pH (>90%), below 50 cm in water depth (>90%), and cyanobacterial dominating waters (>80%), respectively. Over the test, ABA of PMC were more obvious on the algal biomass (chlorophyll-${\alpha}$) than suspended solids, suggesting a selectivity of PMC to particle size or natures. These results suggest that PMC agents can play an important role as natural agents to remove the nuisant algal aggregates or seston of eutrophic lake, where occur cyanobacterial bloom in a shallow shore of lake during warm season.

Turion as Dormant Structure in Spirodela polyrhiza (개구리밥 휴면구조 잠아의 구조적 특성)

  • Kwak, Mi-Young;Kim, In-Sun
    • Applied Microscopy
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    • v.38 no.4
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    • pp.307-314
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    • 2008
  • Hydrophytes such as Spirodela polyrhiza form dormant turions to withstand cold winters. The turion is an anatomically distinct structure from which a vegetative frond arises later during germination. The turions sink to the bottom of the pond when temperatures drop and remain there throughout the winter. In the spring, they float to the surface and germinate into a new frond from the turion primordium. Unlike fronds, turions are known to possess small aerenchyma, starch grains, and relatively dense cytoplasm. These features allow the turions to survive the cold winter season at the bottom of the pond. Spirodela polyrhiza has been investigated previously to a great extent, especially in its physiological, biochemical and ecological attributes. However, a little is known about the structural features of the frond and turion during turion development. Thus, the aim of the present study was to reveal the structural characteristics of the frond and turion with regard to tissue differentiation, aerenchyma development, starch distribution, and ultrastructure, with the use of electron microscopy. A moderate degree of mesophyll tissue differentiation was found in the frond, whereas the turion did not exhibit such differentiation. Within the frond tissue, approximately $37{\sim}45%$ of the cellular volume was occupied by a large aerenchyma, but only $9{\sim}15%$ was taken up by the aerenchyma in the turion. The turion cells, especially those of the turion primordium, were derived from frond cells, and contained cytoplasm. Their cytoplasm was densely packed with plastids, mitochondria, endoplasmic reticulum, Golgi bodies, and microtubules. Plasmodesmata were also well developed within these cells. The most striking feature observed was the distribution of starch grains within the plastids of turion cells. Before the turion sank to the bottom of the pond, a considerable amount of starch accumulated in the plastid stroma. The starch grains dissolved when temperatures rose in the spring, and this promptly provided the nutrients which the primordium needed for turion germination. The turion therefore, was an appropriate dormant structure for free-floating, reduced hydrophytes like Spirodela polyhriza due to its small aerenchyma and large starch grains that aided in the purpose of sinking below the surface of the water to survive cold winters. The new fronds that arose from such turions grew rapidly in the spring, beginning the new life cycle.

Study on the Establishment of Project Duty of Water and Facility Capacity in Upland Irrigation - On the Estimation of Duty of Water for the Upland Crops by the Measurement of Evapotranspiration - (밭 관개의 계획용수량 및 시설용량의 정립에 관한 연구 -증발산량 실측에 의한 밭용수량의 추정에 관하여-)

  • 김시원;김선주
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.30 no.4
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    • pp.23-44
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    • 1988
  • The evaportranspiration of upland crops was measured by four types of lysimeter and water consumption characteristics together with the optimum irrigation point by the crops was defind. Among the evapotranspiration estimation formulas, the constant of wind function in the modified Penman equation was corrected to agree with the meteorological conditions of Korea. The evapotranspiration of the crops in the project standard year was estimated according to the cropping system of the project area in Chungju, and from the estimated evapotras - spiration, net duty of water per one time and irrigation in tervals were investigated. The results obtained are summarized as follows: 1. The evapotranspiration of the same crop measured at the same plot was slightly different by the lysimetric methods, and among the four types of lysimeter, the accuracy of the floating lysimeter was the highest. 2. The yields among the watering treatments showed the significance of 5% in the expe- riment with red cabbage and Chinese cabbage, and significance of 1% in the crisphead lettuce, and the optimum irrigation point for the tested crops was defined ad pF 2.0 by the least squre difference test. 3. The evapotranspiration of the crops in the mid-season stage showed maximum among the growing stages, and the average daily evapotranspiration by the crops over the growing seasons of cabbage, crisphead lettuce, Chinese cabbage, summer cucumber, tornato, salary and autumn cucumber was 4.18mm, 4.77mm, 3.9qrnm, 5.68mnn, joonim, 4.26mm and 3.3qrnn, respectively. 4. From the investigated soil moisture extration pattern(SMEP) of the crisphead lettuce, cucumber and tomato, the proportion of the first layer in the initial stage showed over so%, and the SMEP of the lowest fourth layer during the late-season stage in the experiment cabbage and Chinese cabbage was 15.8% and 16.9, respectively, with showed that the root elongated th the lowest soil layer. 5. The total available moisture(TAM) of clay loam was 21.2-23.3mm and that of sandy loam was 16.1 - 19.0mm under the optimum irrigation point of pF. 2.0, and the total readily available moisture( TRAM) of the crops cultivated in the clay loam soil was larger than that cultivated in the sandy loam soil, and the TRAM during the mid-and late-season were larger than that of the inital and crop development stage. 6. The estimated evapotranspration by the corrected Pennam equation, whkh corrected the constant of the wind function in the modified Penman equation, was nearly agreed with the actually measured evaporanspiration of grass. 7. Among the several evaportranspiration estimation methods, the evapotranspiration es- timated by the corrected Pennam equation was closed to the actual evapotranspiration of reference crop (grass) evapotranspiration, therefore it is suggested to use the corrected Penman equation to determine the duty of water of corps. 8. The average crop coefficient (Kc) of cabbage by the corrected Penman equation was 0.94 and that of crisphead lettuce, summer cucumber, tomato, salary, Chinese cabbage and autumn cucumber was 1.07, 1.22, 1.02, 1.01, 1.35, 1.09, respectively 9. The estimated total evapotranspiration of cabbage in the project area( Chungju) by the corrected Penman equation was 223.9mm and that of crisphead lettuce, Chinese cabbage, summer cucumber, tomato, salary and auturun cucumber was 215.7mm, 205.9mm, 359.Omrn, 300.9mm, 332.lmm and 202.7mm, respectively. 10. The net duty of water per one time of the crops cultivated in the sandy loam soil, and the net duty of water per one time in the mid-season & late-season showed larger than that of the initial stage. 11. The shortest irrigation interval of cabbage in the project area was 4.2 days, and that of crisphead lettuce, Chinese cabbage, cucumber, tomato and salary was 1.2days, 2.3days, 1.8days, 2.2days and 2.7days, respectively.

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