• Title/Summary/Keyword: Decrease temperature

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Evaluation of Soil and Fertilizer Management Techniques Applied by Farmers in Forcing and Semi-forcing Cucumber Cultivation Facilities (오이 촉성재배와 반촉성재배 농가들의 토양 및 시비관리기술 평가)

  • Lee, Ju-Young;Jang, Byoung-Choon;Sung, Jwa-Kyung;Lee, Su-Yeon;Kim, Rog-Young;Lee, Ye-Jin;Park, Yang-Ho;Kang, Sung-Soo;Hyun, Byung-Keun
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.983-991
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    • 2012
  • These days, agricultural products cultivated in facilities occupy the highest percentage of agricultural output price. Specifically cucumbers have been one of the crops that farmers prefer to growing, because their prices were high. However, cucumber crop is sensitive to the soil and environments and it requires the exact crop management. In order to establish cultivation techniques for cucumbers, the current situation of cucumber cultivation was surveyed from ten cucumber farmlands; five farmlands of cucumber cultivation in forcing and five of semi-forcing practicing systems, respectably. The soil conditions were alluvial or valley in soil topology, moderately or poorly drainage in soil drainage classes, coarse loamy in soil texture family. Soil was managed with deep plowing combined with application of basal fertilizers such as compost, rice straw, oil cake, wood chip and chemical fertilizer. The whole soil was prepared in uniformly with rotary. Three major nutrients ($N-P_2O_5-K_2O$)of basal application were 815-464-529 kg $ha^{-1}$ in forcing and 197-135-151 kg $ha^{-1}$ in semi-forcing cultivation. Top dressing of fertilizer was supplied in fertigation system of macro and micro elements in 2~3 day interval with water irrigation. The average yields of cucumbers were $168t\;ha^{-1}$ with 381,000 thousand won $ha^{-1}$ in average gross profit (AGP) in forcing cultivation and $115t\;ha^{-1}$ with 177,000 thousand won $ha^{-1}$ in AGP in semi-forcing cultivation. Cucumber production during the winter season was considered to increase the gross profit because cucumber price tends to stay in high level during this time. The accumulation of soil chemicals like EC, available $P_2O_5$ and exchangeable cations could be controlled by rice straw application. The rice straw application increased soil temperature during the winter season, in exchange of soil air, and in extension of plant roots. In addition, the rice straw application somewhat affected decrease of salts accumulation.

Comparison of Growth Period and Local Climate for 'Hongro' Apple Orchards Located at Different Altitudes in Jangsu-Gun (장수군의 해발고도별 '홍로' 사과원의 미기상 및 생육기 비교)

  • Song, Ju-Hee;Seo, Byung Sun;Choi, Dong Geun;Choi, In Myung;Kang, In-Kyu;Guak, Sunghee
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.15 no.1
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    • pp.1-8
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    • 2013
  • This study was conducted to compare the local climate conditions and growth periods for the apple (Malus domestica 'Borkh') orchards at different altitudes (330, 500, and 670 m) in Jangsu-Gun, Korea. Observation data for the growth period show that the monthly mean air temperatures at the 'Hongro' apple orchard sites decrease with height at the rate of 1.0 to $3.0^{\circ}C$/100 m. The monthly minimum temperatures in April (blooming period for 'Hongro' apple) were 4.3, 2.9, and $0.4^{\circ}C$ at 330, 500, and 670 m, respectively. The monthly mean temperatures in September (i.e., the coloration and maturation period) were 20.6, 18.7, and $14.5^{\circ}C$, respectively. The annual precipitation range varied from 1,234 to 1,439 mm, which tended to increase with height. The heavy rainfall occurred in summer (June to August) and amounted to 827-933 mm. No significant differences in the duration of sunshine were observed amongst the orchards at three different altitudes. The earliest bud break was observed at the 330 m altitude (18 March 2009), which was 4 and 11 days earlier in comparison to those at 500 and 670 m, respectively. The time of full bloom at 330 m was 12 days ahead of that at 670 m. The optimal maturation of fruit (based on skin redness > 80%) was observed between 7 and 10 September at 330 m, 15 and 18 September at 500 m, and 21 and 23 September at 670 m.

Evaluation of the Shear Strength and Stiffness of Frozen Soil with a Low Water Content (함수비가 낮은 동결토의 전단강도 및 강성 평가)

  • Kim, Sang Yeob;Lee, Jong-Sub;Kim, Young Seok;Byun, Yong-Hoon
    • The Journal of Engineering Geology
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    • v.25 no.1
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    • pp.93-102
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    • 2015
  • The characteristics of frozen soils are one of most important factors for foundation design in cold region. The objective of this study is to evaluate the shear strength and stiffness of frozen soils according to the confining conditions during the freezing and shearing phase. A direct shear box is constructed for the frozen specimens and bender elements are mounted on the wall of the shear box to measure shear wave velocities. Specimens are prepared by mixing sand and silt with a silt fraction of 30% in weight and the degree of saturation of 10%, giving a relative density of 60% for all tests. The temperature of the specimens in the freezer is allowed to fall below -5℃, and then direct shear tests are performed. A series of vertical stresses are applied during the freezing and shearing phase. Shear stress, vertical displacement, and shear wave along the horizontal displacement are measured. Experimental results show that in all the tests, shear strength increases with increasing vertical stress applied during the freezing and shearing phases. The magnitude of the increase in shear strength with increasing vertical stress during shearing under fixed vertical stress in the frozen state is smaller than the magnitude of the increase in vertical stress during freezing and shearing. In addition, the change in shear wave velocities varies with the position of the bender elements. In the case of shear waves passing through the shear plane, the shear wave velocities decrease with increasing horizontal displacement. This study provides an evaluation of the properties of shear strength and stiffness of frozen soils under varied confining condition.

Microbial Population of Foodborne Pathogens during Fermentation of Mulberry Wort (오디 발효액의 발효기간 동안 식중독 세균수의 변화)

  • Han, Sanghyun;Ryu, Song Hee;Park, Woonra;Lim, Euna;Kim, Se-Ri;Kim, Won-Il;Yun, Bohyun;Kim, Hyun-Ju;Ryu, Jae-Gee
    • Journal of Food Hygiene and Safety
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    • v.31 no.6
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    • pp.458-464
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    • 2016
  • Mulberry is considered a healthy food for antioxidants and many other beneficial nutrients. However, food safety concerns exist as this commodity scarcely passes through a sanitizing step due to the fragile nature of mulberry fruits. Fermented mulberry wort is one traditional way to utilize and preserve mulberries by mixing with sugars although hygienic practices are not often implemented. The purpose of this study was to investigate the fate of foodborne pathogens in fermented mulberry wort. Microbial population of inoculated E. coli in mulberry wort showed a decreasing pattern as the fermentation progressed. A quicker decrease was observed in the mulberry wort mixed with sugar at 1 to 0.8 ratio (w/w, mulberry: sugar) compared to 1 to 1 ratio, which could be due to the amount of acids generated during the fermentation process. When fully-fermented mulberry wort was contaminated with foodborne pathogens, they all decreased in population although their deceasing patterns varied depending on the species of tested bacteria. Steep deceases in population of inoculated foodborne pathogens were observed when the fermented wort was stored at $30^{\circ}C$ in comparisons to the other storage temperature, 5 and $20^{\circ}C$, regardless of bacterial species. This study necessitates the optimization of a sanitizing process during fermentation and storage of mulberry wort.

Cooking and textural properties of specialty germinated brown rices (기능성 쌀 품종 발아현미의 취반 및 식감특성)

  • Cho, Dong-Hwa;Park, Hye-Young;Lee, Seuk-Ki;Park, Jiyoung;Choi, Hye-Sun;Woo, Koan-Sik;Kim, Hyun-Joo;Sim, Eun-Yeong;Ahn, Eok-Keun;Oh, Sea-Kwan
    • Korean Journal of Food Science and Technology
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    • v.49 no.6
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    • pp.575-583
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    • 2017
  • Germination is a well-known economical technique that has been utilized to enhance the nutritional value of brown rice. Owing to its higher nutritive quality, germinated brown rice has received significant attention in the past decade. In this study, the physicochemical and cooking properties of specialty brown rice (SBR) were analyzed before and after germination. Germination enhanced cooking properties such as water absorption, expanded volume, and increased solid solubility of cooked SBR. The SBR texture measured using tensipresser, was significantly improved by germination. The hardness of cooked SBR was decreased by germination, but stickiness was increased. Pasting analysis of the SBR flours revealed a decrease in all viscosity values (peak viscosity, breakdown, setback, and final viscosity) after germination. However, the gelatinization temperature remains unchanged upon germination. Additionally, amylose content and amylopectin chain length distribution of SBR starch were slightly changed by germination. These results indicate that germination leads to a substantial improvement in the cooking properties and texture of SBR.

A Study on Fuel Quality Characteristics of F-T Diesel for Production of BTL Diesel (BTL 디젤 생산을 위한 F-T 디젤의 연료적 특성 연구)

  • Kim, Jae-Kon;Jeon, Cheol-Hwan;Yim, Eui-Soon;Jung, Choong-Sub;Lee, Sang-Bong;Lee, Yun-Je;Kang, Myung-Jin
    • Journal of the Korean Applied Science and Technology
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    • v.29 no.3
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    • pp.450-458
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    • 2012
  • In order to reduce the effects of greenhouse gas (GHG) emissions, the South Korean government has announced a special platform of technologies as part of an effort to minimize global climate change. To further this effort, the Korean government has pledged to increase low-carbon and carbon neutral resources for biofuel derived from biomass to replace fossil and to decrease levels of carbon dioxide. In general, second generation biofuel produced form woody biomass is expected to be an effective avenue for reducing fossil fuel consumption and greenhouse gas (GHG) emissions in road transport. It is important that under the new Korean initiative, pilot scale studies evolve practices to produce biomass-to-liquid (BTL) fuel. This study reports the quality characteristics of F-T(Fischer-Tropsch) diesel for production of BTL fuel. Synthetic F-Tdiesel fuel can be used in automotive diesel engines, pure or blended with automotive diesel, due to its similar physical properties to diesel. F-T diesel fuel was synthesized by Fischer-Tropsch (F-T) process with syngas($H_2$/CO), Fe basedcatalyst in low temperature condition($240^{\circ}C$). Synthetic F-T diesel with diesel compositions after distillation process is consisted of $C_{12}{\sim}C_{23+}$ mixture as a kerosine, diesel compositions of n-paraffin and iso-paraffin compounds. Synthetic F-T diesel investigated a very high cetane number, low aromatic composition and sulfur free level compared to automotive diesel. Synthetic F-T diesel also show The wear scar of synthetic F-T diesel show poor lubricity due to low content of sulfur and aromatic compounds compared to automotive diesel.

Experimental Studies on Uterine Catecholamines (Catecholamines에 관(關)하여 -제5편(第五編) : 자궁(子宮) catecholamines에 관한 실험적(實驗的) 연구(硏究)-)

  • Lee, Woo-Choo
    • The Korean Journal of Pharmacology
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    • v.19 no.1
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    • pp.37-60
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    • 1983
  • The uterus receives adrenergic terminals from the mesenteric ganglia and considerably large amount of catecholamines have been shown to be contained in this organ. On the other hand, the activities of epinephrine, norepinephrine or adrenergic nerve on uterine motility is so complicated that many controversial results have been reporter. Recently, a large number of reports concerning the changes of uterine catecholamines content have appeared, but little is known about the role of uterine catecholamines in their activities on uterine motility. The present experiments were undertaken to determine the significance of the intrinsic uterine catecholamines in the physiology of uterus. Female albino rabbits weighing approximately 2 kg were employed in this experiment. uterine strip3 were prepared and suspended in a constant temperature $bath(38^{\circ}C)$ containing 100 ml of Locke's solution aerated with 95% oxygen and 5% carbon dioxide. Spontaneous motility was recorded on a smoked drum with an isotonic lever. The catecholamines concentration of the uterus was determined according to the Procedure described of Shore and Olin (1958). Human uterus obtained from patients was also used to determine the catecholam ines content of myometrium. Followings are summarized results. 1) On the non-pregnant rabbit uterine strips, epinephrine and norepinephrine significantly elevated the tonus and stimulated the spontaneous motility. Pretreatment with dichloroisoproterenol(DCI), an adrenergic beta-receptor blocker, enhanced the stimulatory activity of epinephrine or norepinephrine. On the other hand, pretreatment with dibenamine, an adrenergic alpha-receptor blocker, rendered the uterine muscle to exhibit inhibition after the administration of epinephrine or norepinephrine. Following the treatment with both DCI and dibenamine, epinephrine or norepinephrine produced no appreciable effects on the spontaneous motility of the uterus. These results suggest there exist both alpha and beta-adrenergic receptors in the uterine muscle and the response to epinephrine of the former is predominant over that of latter in the non-pregnant uterus of rabbits. The total catecholamines concentration of the non-pregnant uterus was $351\;m{\mu}g/g$ and the fractional concentrations of epinephrine and norepinephrine were $125\;m{\mu}g/g(35.7%)$ and $226\;m{\mu}g/g$ respectively. It is interesting to note that the catecholamines content of uterus was characterized by a high fractional corcentration of epinephrine relative to norepinephrine. 2) On the pregnant rabbit uterine strips, the effects of epinephrine and norepinephrine varied according to the period of pregnancy. The response to epinephrine of adrenergic beta receptor of uterus increased during pregnancy, and the effect of catecholamine was inhibitory in the early pregnancy but became stimulatory as the pregnancy progressed. This stimulating action on the uterine motility was found to occur through the action of norepinephrine. The uterine catecholamines concentration was markedly reduced during pregnancy. The catecholamines concentration was started to decrease in the early pregnancy, reached the lowest level in the mid-pregnancy and then started to increaae again in the late pregnancy when the total catecholamines content became the highest level of all. This increase of catefholamines in late pregnancy was chiefly due to the increase of norepinephrine. These results suggest that the uterine motility may be related to the catecholamines content, especially norepinephrine content in the uterus. 3) Bilateral oophorectomy of rabbits results in a marked shrink of the uterus in size. The spontaneous motility of the uterine segment of these animals was very weak and irregular. Norepinephrine produced inhibitory effect, whereas epinephrine was stimulatory or inhibitory effect on the uterine segment. The total catecholamines tontent in whole uterus was markedly reduced. The injection of estrogen into the oophorectornized rabbit increased the weight of uterus to approximately three times of that of oophorectornized animal. The apontaneous motility and the response to epinephrine and norepinephrine of the uterine segment were greatly enhanced. Both epinephrine and norepinephrine produced a marked stimulatory effects of the uterine motility. The uterine content of catecholamines, particularly epinephrine, was markedly increased. The injection of progesterone into the oophorectornized rabbit increaeed the weight of uterus to approximately 2.5 times of that of eophorectornized animal. The spontaneous motility of the uterine segment was weak and irregular. Epinephrine produced stimulatory effect at high concentrations but norepinephrine always prcdnced inhibitory effect on the uterine segment. The uterine content of catecholamines, particularly of norepinephrine, was markedly reduced. These results suggested that ovarian hormones play an important role not only on the growth and spontaneous norepinephrine of uterus but also on the catecholamines content and responee to epinephrine and norepinephrine of the uterus. 4) The intraperitoneal injection of reserpine(3 mg/kg) into the non-pregnant, pregnant and oophorectornieed rabbits markedly decreased the uterine content of catecholamines, particularly of the norepinephrine. The stimulatory response to epinephrine and. norepinephrine of the uterine segment of these reserpinized ratbits was markedly reduced whereas the inhibitory response to these catecholamines was enhanced. This finding further support the close relationship between the uterine catecholamines content and uterine response to epineptrire and norepinephrine. 5) In the human uterus, the concentration of epinephrine was actrally greater than that of norepinephrine and it was significantly greater during the proliferative phase of the menstrtal cycle. In the human pregnant uterus, the concentrations of toth epinephrine and ncrefinephrine were markedly reduced and showed about 45 percent rednction after 6-8 weeks of ectopic Pregnancy. At full term ana during labor, the concentrations of epinephrine and norepinephrine at placental sites were less than those found in the non-pregnant group. Of interest was the finding that the norepinephrine concentration of uterus from toxemic patients was two and half times higher than that of lower uterine segment of the nontoxemic pregnant individuals. Also the epinephrine concentraticn was slightly increaeed.

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Effects of Sodium Sulfite and Extrusion on the Nutritional Value of Soybean Products for Nursery Pigs

  • Burnham, L.L.;Kim, I.H.;Kang, J.O.;Rhee, H.W.;Hancock, J.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.11
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    • pp.1584-1592
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    • 2000
  • Three hundred nursery pigs were used in two growth assays (avg initial BW of 6.5 and 6.0 kg, respectively) to determine the effects of sodium sulfite ($Na_2SO_3$) as an extrusion aid for soy products used in diets for weanling pigs. In Exp. 1, treatments were arranged as $3{\times}2$ factorial with main effects of soy product [soybean meal (SBM), extruded SBM, and dry-extruded whole soybeans (DEWS)] and concentration of $Na_2SO_3$ (0 and 10 g/kg of soy product). The extruded SBM and DEWS treatments were processed in a dry extruder ($Insta-Pro^{(R)} $, Triple F Nutrition, Des Moines, IA) with barrel temperatures and throughputs of $169^{\circ}C$ and 578 kg/h, and $147^{\circ}C$ and 598 kg/h, respectively. All diets were formulated to 3.5 Mcal/kg DE, with 0.92% lysine for d 0 to 14, and 0.76% lysine for d 14 to 28. For d 0 to 14, there was a tendency for pigs fed diets with $Na_2SO_3$ to have greater ADG (p<0.08), and pigs fed SBM to have greater ADFI (p<0.02), thus pigs fed the extruded soy products has 15% greater gain/feed than those fed SBM (p<0.007). For d 14 to 28, there were no differences in ADG or gain/feed among pigs fed diets with SBM and those fed diets with the extruded soy products (p>0.15). However, pigs fed DEWS had greater ADG than pigs fed extruded SBM, and pigs fed $Na_2SO_3$ had greater ADG and ADFI compared to those not fed $Na_2SO_3$ (p<0.02 and 0.08, respectively). The positive response in ADG and gain/feed to the addition of $Na_2SO_3$ resulted with SBM and extruded SBM treatments, and not with DEWS (interaction effect, p<0.04). Overall (d 0 to 28), pigs fed DEWS had greater ADG (p<0.01) and gain/feed (p<0.08) than pigs fed extruded SBM. Also pigs fed diets with $Na_2SO_3$ had greater ADG, ADFI, and gain/feed compared to those fed diets without $Na_2SO_3$ (p<0.002, 0.04, and 0.04, respectively). Exp. 2 was designed as a $2{\times}3$ factorial with main effects of soy product (SBM and DEWS) and concentration of $Na_2SO_3$ (none, 7.5, and 15.0 g/kg of soy product). As in Exp. 1, all diets were formulated to 3.5 Mcal/kg DE, with 0.92% lysine for d 0 to 13, and 0.76% lysine for d 13 to 53. At a constant processing temperature (148 to $149^{\circ}C$, $Na_2SO_3$ increased throughput of the extruder (578, 595, and 602 kg/h for the 0, 7.5, and 15.0 g/kg additions, respectively). For d 0 to 13, treatment had no effect on ADG or ADFI, but gain/feed decreased for pigs fed SBM with increasing concentrations of $Na_2SO_3$, and increased for pigs fed DEWS with increasing concentrations of $Na_2SO_3$ (SBM vs DEWS sulfite quadratic interaction, p<0.03). For d 13 to 35, pigs fed DEWS had greater ADG (p<0.01) and gain/feed (p<0.001) than pigs fed SBM. Also, ADFI decreased and gain/feed increased with increasing concentrations of $Na_2SO_3$ (linear effects, p<0.04 and 0.01, respectively). Overall, pigs fed the diets with DEWS had greater ADG and gain/feed than pigs fed SBM (p<0.003 and 0.002, respectively), and $Na_2SO_3$ tended to decrease ADFI and increase gain/feed (linear effects, p<0.07 and 0.06, respectively). In conclusion, pigs fed DEWS had greater rate and efficiency of gain than pigs fed SBM. Also, adding $Na_2SO_3$ prior to extrusion increased yield and feed efficiency.

Food Composition of Crab(Charybdis japonica) Preserved in Brine (민꽃게(Charybdis japonica)장의 식품 성분)

  • Park, IL-Woong;Kim, Hyun-Su;Choe, Kyu-Hong;Choe, Sun-Nam;Kim, Jung-Bae;Lim, Sung-Han
    • Journal of Fisheries and Marine Sciences Education
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    • v.20 no.1
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    • pp.95-106
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    • 2008
  • Pickled crabs made using Charybdis japonica are becoming part of our dietary habits. Yet research on this food is disappointingly scarce. It is generally accepted that the original food composition of pickled crabs defies scrutiny because various seasonings are added to soy for the production of pickled crabs in most regions. Accordingly, this study attempted to measure the food composition of the Charybdis japonica preserved in brine according to different storage days (10, 15, 20, 25, and 30 days) and different temperatures ($5{^{\circ}C}$, $15{^{\circ}C}$, and ambient temperature). It was found that Charybdis japonica is comprised of moisture (77.5%), ash (2.3%), crude protein (19.7%), and crude lipid (0.5%). The content of crude protein and crude lipid during the storage period tended to decrease over time.

Fertilizer demand estimated in aspect of crop nutrition (작물영양면(作物營養面)에서 본 비료(肥料)의 수요전망(需要展望))

  • Park, Hoon;Park, Young Sun
    • Korean Journal of Soil Science and Fertilizer
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    • v.9 no.3
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    • pp.165-181
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    • 1976
  • Fertilizer(N,P,K) demand for crop production in 1980, 1990 and 2000 was estimated according to the two proposed models, one of which is fertilizer use efficiency model expressed in $Fn=(Y/E){\cdot}(1-Cs)Eu$, where Fn:fertilizer demand, Y:Crop production estimated, E:nutrient efficiency, Cs:fraction of natural resource nutrient in plant, Eu:fertilizer use efficiency and the other fertilization efficiency model expressed in Fn=Y(1-Cys)/Fe, where Cys:fraction of yield without fertilizer, Fe:fertilization efficiency. Total crop uptake of nutrient and its noncycling portion were estimated as criteria for fertilizer demand and nutrient maintenance. Total crop uptake of N,P,K was 600,000 M/T in 1965 700,000 M/T in 1974 and estimated to 880,000 M/T in 1980, 1,170,000 M/T in 1990 and 1,410,000 M/T in 2000. Fertilizer demand appeares to be about 90% of total crop uptake according to fertilizer use efficiency model and about 87% according to fertilization efficiency model. The noncycling nutrient was about 29% of total crop uptake. Fertilizer demand was almost same to the uptake amount in nitrogen, 1.5 times of uptake in phosphorus and half of uptake in potassium. Varietal development, improvement of soil fertility and cultivation method and development of fertilizer forms appears to decrease fertilizer demand by increasing efficiency term in two models while environmental stress such as low temperature appears to give reverse effect resulting in higher fertilizer demand. Fertilizer consumption in 1974 seemed to be unreasonably high especially in nitrogen and phosphorus and thus the effective use of fertilizer appeared as an urgent problem considering that large fields are still remained in lower fertility.

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