• Title/Summary/Keyword: Carbon/carbon

Search Result 26,591, Processing Time 0.057 seconds

Environmental Management of Marine Cage Fish Farms using Numerical Modelling (수치모델을 이용한 해상어류가두리양식장의 환경관리 방안)

  • Kwon, Jung-No;Jung, Rae-Hong;Kang, Yang-Soon;An, Kyoung-Ho;Lee, Won-Chan
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.10 no.4
    • /
    • pp.181-195
    • /
    • 2005
  • To study the effects of aquaculture activity of marine cage fish farms on marine environment, field researches including hydrography, sediment, benthos and trap experiment at the marine cage fish farms(Site A) around estuaries of Tongyeong city were carried out during June $26\~27$, 2003. A simulation using numerical model-DEPOMOD was conducted to predict the solid deposition from fish cage and to assess the probable solid deposition, and the efficiency of environmental management of marine cage fish farms was studied. The marine cage fish farms cultured mainly common sea bass (Lateolabrax japonicus), red seabream (Pagrus major), striped breakperch (Oplegnathus fasciatus) and black rockfish(Sebastes schlegeli), and total amount of cultured fish of the Site A were 23.1MT. The amount of husbandry fish by unit area(and volume) of the fish cage was $43.0kg\;m^{-2}(6.1kg\;m^{-3})$. The daily mean amounts of food fed by unit biomass and cage area were $30.8g\;kg^{-1}day^{-1},\;1.32kg\;m^{-2}day^{-1},$ respectively, at the Site A. The concentration of ORP of the sediment below the center at the Site A was -334.6 mV and the concentrations of AVS, COD, Carbon and Nitrogen were $0.43mg\;g^{-1}dry,\;17.75mg\;g^{-1}dry,\;10.19mg\;g^{-1}dry\;and\;3.49mg\;g^{-1}dry$, respectively. Capitella capitata was dominant benthic species which occupied $57.8\%$ of total species, and the Infaunal Trophical Index(ITI) was marked below 20 within 20 m distance from the edge of the Site A. The result of trap experiment, the solid deposition from the Site A was $34,485g\;m^{-2}yr^{-1}$ at 0 m from the center of the cage and $18,915g\;m^{-2}yr^{-1}$ at 42 m. From a model simulation, it was estimated that using a model simulation, the proportion of unfed food was $40\%$ at the Site A and the annual total amount of solid deposition was 63,401 accounting for $24.4\%$ of the annual total food fed at the Site A. The area solid deposition settled was estimated to be $8,450m^2$, which was about 16 times of the total area of fish cage at the Site A. And concerning ITI and abundance of benthos, the model predicted that sustainable solid flux at the Site A was below $10,000gm^{-2}yr^{-1}$. The percentage of food wasted was main element of solid deposition at the marine cage fish farms, and for minimizing solid deposition it is necessary to increase the efficiency of the food uptake. Based on the result of the model simulation, if the percentage of food wasted decreases to $10\%$ from the current $40\%$, then the solid deposition could decrease to a half. In addition, it was predicted that if farmers use EP pellets as food fed instead of MP and fish trash, solid deposition could decrease by $57\%$. Also this study proposes that the cage facility ratio of the licensed area be decreased to less than $5\%$ to minimize the sediment pollution.

Taxonomical Classification and Genesis of Jeju Series in Jeju Island (제주도 토양인 제주통의 분류 및 생성)

  • Song, Kwan-Cheol;Hyun, Byung-Geun;Moon, Kyung-Hwan;Jeon, Seung-Jong;Lim, Han-Cheol;Lee, Shin-Chan
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.43 no.2
    • /
    • pp.230-236
    • /
    • 2010
  • Jeju Island is a volanic island which is located about 96 km south of Korean Peninsula. Volcanic ejecta, and volcaniclastic materials are widespread as soil parent materials throughout the island. Soils on the island have the characteristics of typical volcanic ash soils. This study was conducted to reclassify Jeju series based on the second edition of Soil Taxonomy and to discuss the formation of Jeju series in Jeju Island. Morphological properties of typifying pedon of Jeju series were investigated, and physico-chemical properties were analyzed according to Soil survey laboratory methods manual. The typifying pedon has dark brown (10YR 3/3) silt clay loam A horizon (0~22 cm), strong brown (7.5YR 4/6) silty clay BAt horizon (22~43 cm), brown (7.5YR 4/4) silty clay Bt1 horizon (43~80 cm), brown (7.5YR 4/6) silty clay loamBt2 horizon (80~105 cm), and brown (10YR 5/4) silty clay loam Bt3 horizon (105~150 cm). It is developed in elevated lava plain, and are derived from basalt, and pyroclastic materials. The typifying pedon contains 1.3~2.1% oxalate extractable (Al + 1/2 Fe), less than 85%phosphate retention, and higher bulk density than 0.90 Mg $m^{-3}$. That can not be classified as Andisol. But it has an argillic horizon from a depth of 22 to 150 cm, and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. That can be classified as Ultisol, not as Andisol. Its has 0.9% or more organic carbon in the upper 15 cm of the argillic horizon, and can be classified as Humult. It dose not have fragipan, kandic horizon, sombric horizon, plinthite, etc. in the given depths, and key out as Haplohumult. A hoizon (0~22 cm) has a fine-earth fraction with both a bulk density of 1.0 Mg $cm^{-3}$ or less, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0. Thus, it keys out as Andic Haplohumult. It has 35% or more clay at the particle-size control section, and has thermic soil temperature regime. Jeju series can be classified as fine, mixed, themic family of Andic Haplohumults, not as ashy, thermic family of Typic Hapludands. In the western, and northern coastal areas which have a relatively dry climate in Jeju Island, non Andisols are widely distributed. Mean annual precipitation increase 110 mm, and mean annual temperature decrease $0.8^{\circ}C$ with increasing elevation of 100m. In the western, and northern mid-mountaineous areas Andisols, and non Andisols are distributed simultaneously. Jeju series distributed mainly in the western and northern mid-mountaineous areas are developed as Ultisols with Andic subgroup.

The Clinical Effects of Normocapnia and Hypercapnia on Cerebral Oxygen Metabolism in Cardiopulmonary Bypass (체외순환 시 뇌대사에 대한 정상 탄산분압과 고 탄산분압의 임상적 영향에 관한 비교연구)

  • 김성룡;최석철;최국렬;박상섭;최강주;윤영철;전희재;이양행;황윤호
    • Journal of Chest Surgery
    • /
    • v.35 no.10
    • /
    • pp.712-723
    • /
    • 2002
  • Substantial alterations in cerebral blood flow(CBF) are known to occur during cardiopulmonary bypass(CPB). Many investigators have speculated that these changes may be responsible for both minor and major cerebral damages after CPB. More recently, these changes in CBF have been observed to be intimately related to the arterial carbon dioxide tension(Pa$CO_2$) maintained during CPB. The present study was prospectively designed to investigate the clinical effects of normocapnic and hypercapnic CPB on the cerebral oxygen metabolism in cardiac surgery Material and Method: Thirty-six adult patients scheduled for elective cardiac surgery were randomized to either normocapnic group (Pa$CO_2$35~40 mmHg, n=18) or hypercapnic group(Pa$CO_2$, 45~55 mmHg, n=18) with moderately hypothermic nonpulsatile CPB(nasopharyngeal temperature of 29~3$0^{\circ}C$). In each patient, middle cerebral artery blood flow velocity( $V_{MCA}$), cerebral arteriovenous oxygen content difference (C(a-v) $O_2$), cerebral oxygen extraction(COE), cerebral metabolic rate for oxygen(CMR $O_2$), cerebral oxygen transport( $T_{E}$ $O_2$), $T_{E}$ $O_2$/CMR $O_2$ ratio, cerebral desaturation(internal jugular bulb blood oxygen saturation $\leq$ 50%), and arterial and jugular bulb blood gas were evaluated throughout the operation. Postoperative neuropsychologic complications were assessed in all patients. All variables were compared between the two groups. Result: VMCA(169.13 $\pm$ 8.32 vs 153.11 $\pm$8.98%), TE $O_2$(1,911.17$\pm$250.14 vs 1,757.40$\pm$249.56), $T_{E}$ $O_2$,/CMR $O_2$ ratio(287.38$\pm$28.051 vs 246.77$\pm$25.84), $O_2$ tension in internal jugular bulb (41.66$\pm$9.19 vs 31.50$\pm$6.09 mmHg), and $O_2$saturation in internal jugular bulb(68.97$\pm$10.96 vs 58.12$\pm$12.11%) during CPB were significantly lower in normocapnic group(p=0.03), whereas hypercapnic group had lower C(a-v) $O_2$(3.9$\pm$0.3 vs 4.9$\pm$0.3 mL/dL), COE(0.3$\pm$0.03 vs 0.4$\pm$0.03), CMR $O_2$(5.8 $\pm$0.5 vs 6.8$\pm$0.6), and arterial blood pH(7.36$\pm$0.09 vs 7.46$\pm$0.07, p=0.04) during CPB. Hypercapnic group had lower incidence of cerebral desaturation than normocapnic group(3 vs 9 patients, p=0.03). Duration of the neuropsychologic complication(delirium) were shorter in hypercapnic group than in normocapnic group(36 vs 60 hrs, p=0.009). Conclusion: These findings suggest that hypercapnic CPB may have salutary effects on the cerebral oxygen metabolism and postoperative neurologic outcomes in cardiac surgery.surgery.

A Critical Evaluation of the Correlation Between Biomarkers of Folate and Vitamin $B_{12}$ in Nutritional Homocysteinemia (엽산과 비타민 $B_{12}$ 결핍에 의한 호모시스테인혈증 흰쥐의 조직내 비타민 지표간의 상관관계 분석)

  • Min, Hye-Sun;Kim, Mi-Sook
    • Journal of Nutrition and Health
    • /
    • v.42 no.5
    • /
    • pp.423-433
    • /
    • 2009
  • Folate and vitamin $B_{12}$ are essential cofactors for homocysteine (Hcy) metabolism. Homocysteinemia has been related with cardiovascular and neurodegenerative disease. We examined the effect of folate and/or vitamin $B_{12}$ deficiency on biomarkers of one carbon metabolism in blood, liver and brain, and analyzed the correlation between vitamin biomarkers in mild and moderate homocysteinemia. In this study, Sprague-Dawley male rats (5 groups, n = 10) were fed folatesufficient diet (FS), folate-deficient diet (FD) with 0 or 3 g homocystine (FSH and FDH), and folate-/vitamin $B_{12}$-deficient diet with 3 g homocystine (FDHCD) for 8 weeks. The FDH diet induced mild homocysteinemia (plasma Hcy 17.41 ${\pm}$ 1.94 nmol/mL) and the FDHCD diet induced moderate homocysteinemia (plasma Hcy 44.13 ${\pm}$ 2.65 nmol/mL), respectively. Although liver and brain folate levels were significantly lower compared with those values of rats fed FS or FSH (p < 0.001, p < 0.01 respectively), there were no significant differences in folate levels in liver and brain among the rats fed FD, FDH and FDHCD diet. However, rats fed FDHCD showed higher plasma folate levels (126.5 ${\pm}$ 9.6 nmol/L) compared with rats fed FD and FDH (21.1 ${\pm}$ 1.4 nmol/L, 22.0 ${\pm}$ 2.2 nmol/L)(p < 0.001), which is the feature of "ethyl-folate trap"by vitamin $B_{12}$ deficiency. Plasma Hcy was correlated with hepatic folate (r = -0.641, p < 0.01) but not with plasma folate or brain folate in this experimental condition. However, as we eliminated FDHCD group during correlation test, plasma Hcy was correlated with plasma folate (r = -0.581, p < 0.01), hepatic folate (r = -0.684, p < 0.01) and brain folate (r = -0.321, p < 0.05). Hepatic S-adenosylmethionine (SAM) level was lower in rats fed FD, FDH and FDHCD than in rats fed FS and FSH (p < 0.001, p < 0.001 respectively) and hepatic S-adenosylhomocysteine (SAH) level was significantly higher in those groups. The SAH level in brain was also significantly increased in rats fed FDHCD (p < 0.05). However, brain SAM level was not affected by folate and/or vitamin $B_{12}$ deficiency. This result suggests that dietary folate- and vitamin B12-deficiency may inhibit methylation in brain by increasing SAH rather than decreasing SAM level, which may be closely associated with impaired cognitive function in nutritional homocysteinemia.

Relationship of Compliance and Oxygen Transport in Experimental Acute Respiratory Failure during Positive End-Expiratory Pressure Ventilation (실험적 급성호흡부전에서 호기말양압에 의한 폐유순도와 산소운반의 변화 및 상관관계 - 호흡부전의 기전에 따른 차이 -)

  • Lee, Sang-Do;Yoon, Se-Jin;Lee, Bok-Hee;Han, Sung-Koo;Shim, Young-Soo;Kim, Keun-Youl;Han, Yong-Chol
    • Tuberculosis and Respiratory Diseases
    • /
    • v.40 no.1
    • /
    • pp.6-15
    • /
    • 1993
  • Background: Positive end, expiratory pressure (PEEP) has become one of the standard therapies for adult respiratory distress syndrome (ARDS). Total static compliance has been proposed as a guide to determine the size of PEEP ('best PEEP') which is of unproven clinical benefit and remains controversial. Besides increasing functional residual capacity and thus improving oxygenation, PEEP stimulate prostacyclin secretion and was proposed for the treatment of acute pulmonary embolism. But little is known about the effect of PEEP on hemodynamic and gas exchange disturbances in acute pulmonary embolism. Methods: To study the validity of total static compliance as a predictor of 'best PEEP' in ARDS and acute pulmonary embolism, experimental ARDS was induced in mongrel dog with oleic acid and acute pulmonary embolism with autologous blood clot. Then hemodynamic and gas exchange parameters were measured with serial increment of PEEP. Results:In ARDS group, total static compliance and oxygen transport were maximal at 5 cm$H_2O$, and decreased thereafter (p<0.05). With increment of PEEP, arterial oxygen tension ($PaO_2$) and arterial carbon dioxide tension ($PaCO_2$) increased and cardiac output and physiological shunt decreased. In pulmonary embolism group, total static compliance, oxygen transport, physiological shunt and cardiac output decreased and $PaO_2$ and $PaCO_2$ increased with increment of PEEP (p<0.05). Comparing the change induced by increment of PEEP by 1 cm$H_2O$ in ARDS group with that in pulmonary embolism group, there was no significant difference between two groups except cardiac output which decreased more in pulmonary embolism group (p<0.05). In ARDS group, oxygen transport and total static compliance increased after PEEP application, and total static compliance was maximal at the PEEP level where oxygen transport was maximal. However in pulmonary embolism group, oxygen transport and total static compliance decreased after application of PEEP. There was significant correlation between change of total static compliance and change of oxygen transport in both groups. Conclusion: In both ARDS and acute pulmonary embolism, it can be concluded that total static compliance is useful as a predictor of 'best PEEP'.

  • PDF

The Patterns of CH4 and N2O fluxes from used Litter Stockpile from Korean Native Cattle (Hanwoo) (사용한 한우 깔짚에서 배출되는 CH4 및 N2O의 배출 특성)

  • Park, Kyu-Hyun;Choi, Dong-Yoon;Yoo, Yong-Hee
    • Journal of Animal Environmental Science
    • /
    • v.18 no.3
    • /
    • pp.145-150
    • /
    • 2012
  • This study was conducted to measure methane ($CH_4$) and nitrous oxide ($N_2O$) emissions from the 6 month old litter stockpile used for korean native cattle (Hanwoo) from August 3, 2007 to October 4, 2007. Daily mean $CH_4$ emissions was peaked to 273.013 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}1.047{\mu}g\;m^{-2}\;s^{-1}$) on first day and then gradually decreased to 2.309 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.061{\mu}g\;m^{-2}\;s^{-1}$) at the end of this experiment. Daily mean $N_2O$ emissions was as little as 0.269 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.018{\mu}g\;m^{-2}\;s^{-1}$) on first day, but exponentially increased up to 3.569 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.454{\mu}g\;m^{-2}\;s^{-1}$) on 43rd day and then slowly decreased to 1.888 ${\mu}g\;m^{-2}\;s^{-1}$ (SE : ${\pm}0.012{\mu}g\;m^{-2}\;s^{-1}$) at the end of this experiment. Carbon dioxide equivalent ($CO_2$-eq), calculated by global warming potentials of $CH_4$ or $N_2O$, of $CH_4$ on first day occupied approximately 99% of sum of $CO_2$-eq of $CH_4$ and $N_2O$. Methane emissions decreased and $N_2O$ emissions increased so that $CO_2$-eq ratio of $CH_4$ to $N_2O$ was 50:50 on 34th day. The effect of $N_2O$ on the ratio was increase thereafter. The ratio of daily mean $CH_4$ and $N_2O$ emissions to daily error of the mean was calculated to find daily fluctuation of $CH_4$ and $N_2O$ emissions. The ratio of $CH_4$ was less than 1.0% till 11th day but increased to 10.9% on 57th day. The ratio of $N_2O$ (0.4%~51.0%) was higher than that of $CH_4$, showing high in early stage and then gradually decrease, which was different from the pattern of $CH_4$. The ratio of daily mean emissions to daily error of the mean was little in case of active $CH_4$ or $N_2O$ generation period, which would be caused by the temporal and spatial heterogeneity of composting process. Hence more air supply on early stage to decrease $CH_4$ generation and proper turning to reduce spatial heterogeneity are needed to mitigate greenhouse gas emissions.

Research and Development Trends on Omega-3 Fatty Acid Fortified Foodstuffs (오메가 3계 지방산 강화 식품류의 연구개발 동향)

  • 이희애;유익종;이복희
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.26 no.1
    • /
    • pp.161-174
    • /
    • 1997
  • Omega-3 fatty acids have been major research interests in medical and nutritional science relating to life sciences since after the epidemiologic data on Green3and Eskimos reported by several researchers clearly showed fewer per capita deaths from heart diseases and a lower incidence of adult diseases. Linolenic acid(LNA) is an essential fatty acid for human beings as well as linoleic acid(LA) due to the fact that vertebrates lack an enzyme required to incorporate a double bond beyond carbon 9 in the chain. In addition the ratio of omega-6 and 3 fatty acids seems to be important in terms of alleviation of heart diseases since LA and LNA competes for the metabolic pathways of eicosanoids synthesis. High consumption of omega-3 fatty acids in seafoods may control heart diseases by reducing blood cholesterol, triglyceride, VLDL, LDL and increasing HDL and by inhibiting plaque development through the formation of antiaggregatory substances like PGI$_2$, PGI$_3$ and TXA$_3$ metabolized from LNA. Omega 3 fatty acids also play an important role in neuronal developments and visual functioning, in turn influence learning behaviors. Current dietary sources of omega-3 fatty acids are limited mostly to seafoods, leafy vegetables, marine and some seed oils and the most appropriate way to provide omega-3 fatty acids is as a part of the normal dietary regimen. The efforts to enhance the intake of omega-3 fatty acids due to several beneficial effects have been made nowadays by way of food processing technology. Two different ways can be applied: one is add Purified and concentrated omega-3 fatty acids into foods and the other is to produce foods with high amounts of omega-3 fatty acids by raising animals with specially formulated feed best for the transfer of omega-3 fatty acids. Recently, items of manufactured and marketed omega-3 fatty acids fortified foodstuffs are pork, milk, cheese, egg, formula milk and ham. In domestic food market, many of them are distributed already, but problem is that nutritional informations on the amounts of omega-3 fatty acids are not presented on the labeling, which might cause distrust of consumers on those products, result in lower sales volumes. It would be very much wise if we consume natural products, result in lower sales volumes. It would be very much wise if we consume natural products high in omega-3 fatty acids to Promote health related to many types of adult diseases rather than processed foods fortified with omega-3 fatty acids.

  • PDF

Difference in Chemical Composition of PM2.5 and Investigation of its Causing Factors between 2013 and 2015 in Air Pollution Intensive Monitoring Stations (대기오염집중측정소별 2013~2015년 사이의 PM2.5 화학적 특성 차이 및 유발인자 조사)

  • Yu, Geun Hye;Park, Seung Shik;Ghim, Young Sung;Shin, Hye Jung;Lim, Cheol Soo;Ban, Soo Jin;Yu, Jeong Ah;Kang, Hyun Jung;Seo, Young Kyo;Kang, Kyeong Sik;Jo, Mi Ra;Jung, Sun A;Lee, Min Hee;Hwang, Tae Kyung;Kang, Byung Chul;Kim, Hyo Sun
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.34 no.1
    • /
    • pp.16-37
    • /
    • 2018
  • In this study, difference in chemical composition of $PM_{2.5}$ observed between the year 2013 and 2015 at six air quality intensive monitoring stations (Bangryenogdo (BR), Seoul (SL), Daejeon (DJ), Gwangju (GJ), Ulsan (US), and Jeju (JJ)) was investigated and the possible factors causing their difference were also discussed. $PM_{2.5}$, organic and elemental carbon (OC and EC), and water-soluble ionic species concentrations were observed on a hourly basis in the six stations. The difference in chemical composition by regions was examined based on emissions of gaseous criteria pollutants (CO, $SO_2$, and $NO_2$), meteorological parameters (wind speed, temperature, and relative humidity), and origins and transport pathways of air masses. For the years 2013 and 2014, annual average $PM_{2.5}$ was in the order of SL ($${\sim_=}DJ$$)>GJ>BR>US>JJ, but the highest concentration in 2015 was found at DJ, following by GJ ($${\sim_=}SJ$$)>BR>US>JJ. Similar patterns were found in $SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$. Lower $PM_{2.5}$ at SL than at DJ and GJ was resulted from low concentrations of secondary ionic species. Annual average concentrations of OC and EC by regions had no big difference among the years, but their patterns were distinct from the $PM_{2.5}$, $SO{_4}^{2-}$, $NO_3{^-}$, and $NH_4{^+}$ concentrations by regions. 4-day air mass backward trajectory calculations indicated that in the event of daily average $PM_{2.5}$ exceeding the monthly average values, >70% of the air masses reaching the all stations were coming from northeastern Chinese polluted regions, indicating the long-range transportation (LTP) was an important contributor to $PM_{2.5}$ and its chemical composition at the stations. Lower concentrations of secondary ionic species and $PM_{2.5}$ at SL in 2015 than those at DJ and GJ sites were due to the decrease in impact by LTP from polluted Chinese regions, rather than the difference in local emissions of criteria gas pollutants ($SO_2$, $NO_2$, and $NH_3$) among the SL, DJ, and GJ sites. The difference in annual average $SO{_4}^{2-}$ by regions was resulted from combination of the difference in local $SO_2$ emissions and chemical conversion of $SO_2$ to $SO{_4}^{2-}$, and LTP from China. However, the $SO{_4}^{2-}$ at the sites were more influenced by LTP than the formation by chemical transformation of locally emitted $SO_2$. The $NO_3{^-}$ increase was closely associated with the increase in local emissions of nitrogen oxides at four urban sites except for the BR and JJ, as well as the LTP with a small contribution. Among the meterological parameters (wind speed, temperature, and relative humidity), the ambient temperature was most important factor to control the variation of $PM_{2.5}$ and its major chemical components concentrations. In other words, as the average temperature increases, the $PM_{2.5}$, OC, EC, and $NO_3{^-}$ concentrations showed a decreasing tendency, especially with a prominent feature in $NO_3{^-}$. Results from a case study that examined the $PM_{2.5}$ and its major chemical data observed between February 19 and March 2, 2014 at the all stations suggest that ambient $SO{_4}^{2-}$ and $NO_3{^-}$ concentrations are not necessarily proportional to the concentrations of their precursor emissions because the rates at which they form and their gas/particle partitioning may be controlled by factors (e.g., long range transportation) other than the concentration of the precursor gases.

The Effects of Environment-Friendly Agricultural Materials on Soil and the Quality of 'Niitaka' pear's Orchad (친환경농자재 처리가 배과수원 토양 및 과실품질에 미치는 영향)

  • Yoon, Seong-Tak;Xu, Zhen-Yu;Zhang, Qing-Yu;Kim, Tae-Ho;Nam, Jung-Chang;Park, Sang-Hun;Kwak, No-Il;Mun, Su-Hak;Lee, Hyuk-Jae;Choi, Jin-Ho
    • Korean Journal of Organic Agriculture
    • /
    • v.18 no.4
    • /
    • pp.613-626
    • /
    • 2010
  • Coming with the well-being era, consumer's demand for safe agricultural products is increasing. It is urgent to develop an environment-friendly pear production system. Accordingly, this study was conducted to develop an environment-friendly pear production system by using several environment-friendly agricultural materials which is known to be effective in agricultural production. In the effects of environment-friendly agricultural materials on the soil chemical characteristics in pear orchard, the content of total carbon, organic matter, Ca and Mg increased a little respectively compared with those of 2008, and 2nd treatment showed the highest EC and Mg content in the soil among treatments. The content of leaf N, P and Ca in 2009 decreased compared with those of 2008, while Mg content showed no difference between 2008 and 2009 years. Average pear weight in 2009 was 31g higher than that of 2008 (682g) and 2nd treatment showed the highest pear weight (738g) among treatments. The average sugar content was higher in 2009 (12.6$^{\circ}Bx$) compared with that of 2008 (12.2$^{\circ}Bx$) and the plot of 2nd treatment highest sugar content (12.6$^{\circ}Bx$) among treatments. There were no difference in hunter value of L among treatments, but hunter value of a showed higher 1.62 in 2009 than that of 2008 (3.73). The highest of gumminess and cohesiveness of fruits were obtained from 1st treatment and adhesiveness and chewiness of fruits were obtained from 3rd and 1st treatment respectively. Firmness of fruit increased a little in 2009 compared with that of 2008, while the highest firmness was obtained from 3rd treatment with 1.63kg/5mm$\oint$ among treatments. Phosphate content in the peel of 'Niitaka' pear of fruit skin in 2009 (0.97g/kg) showed 0.06g/kg more content than that of 2008 (0.91g/kg), while the highest content was obtained from 3rd treatment (1.15g/kg). Potassium content in the peel of 'Niitaka' pear in 2009 was 8.20g/kg, which is 0.06g/kg more content than that of 2008 (7.82g/kg) and the highest content was obtained from 1st treatment (8.34g/kg) among treatments. The highest nitrogen content in the flesh of 'Niitaka' pear was obtained from 3rd treatment (4.32mg/g), while it was the lowest in control plot (3.10mg/g). Phosphate content in the flesh of 'Niitaka' pear in 2009 (8.20g/kg) showed 0.06g/kg more content than that of 2008 (7.82g/kg), while the highest content was obtained from 1st treatment (8.34g/kg). There were no difference of the potassium content in the fruit peel of 'Niitaka' pear between years, but 1st treatment showed the highest content (11.81g/kg) among treatments, while the lowest was obtained from the control plot (10.83g/kg).

Quality Properties of Chonggak Kimchi Fermented at different Combination of Temperature and Time (발효 온도와 시간 조합을 달리한 총각김치의 품질 특성)

  • Kang, Jeong-Hwa;Kang, Sun-Hee;Ahn, Eun-Sook;Chung, Hee-Jong
    • Journal of the Korean Society of Food Culture
    • /
    • v.18 no.6
    • /
    • pp.551-561
    • /
    • 2003
  • To determine the conditions of the fermentation and storage for Chonggak kimchi in kimchi refrigerator, prepared Chonggak kimchi took into kimchi refrigerators which were controlled at four different modes of the fermented temperature and time, and fermented and kept for 16 weeks. The pH in Chonggak kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ dropped greater than all of kimchi fermented at other combinations, and the changes of pH at any combinations were not greater than those in Baechu kimchi, because pH in Chonggak kimchi did not dropped below 4.5. Acidities in Chonggak kimchi were greatly increased at higher temperature. The acidity in Chonggak kimchi during the first week of fermentation was lower than that in Baechu kimchi and then it was rather higher because of the addition of waxy rice paste. In texture, puncture force of Chonggak kimchi was decreased slowly until 8 weeks of fermentation and then did not changed much and the highest values showed in Chonggak kimchi stored directly at $-1^{\circ}C$ without any fermentation. In sensory evaluation, the scores for the carbonated flavor and the sourness were the highest in Chonggak kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$, but the lowest in Chonggak kimchi stored directly at $-1^{\circ}C$ without any fermentation because of some undesirable flavors. The lowest hardness showed in Chonggak kimchi fermented at highest temperature and the best hardness was in Chonggak kimchi fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$. The appearance was the best in Chonggak kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ and the worst was in Chonggak kimchi stored directly at $-1^{\circ}C$ without any fermentation. The overall acceptability of Chonggak kimchi fermented at $20^{\circ}C$ for 24 hours/stored at $-1^{\circ}C$ was good after 4 weeks of fermentation, but in Chonggak kimchi fermented at $5^{\circ}C$ for 3 days or 6 days/stored at $-1^{\circ}C$ it was good after 6 weeks. Total microbial counts in most of Chonggak kimchi were reached to a maximum number within 7 days, and then decreased similarly at all modes. Leuconostoc spp. and Lactobacillus spp. increased to maximum number of $1.48{\times}10^9\;and\;5.62{\times}10^9$, respectively, in Chonggak kimchi fermented for 7 days. Yeast counts showed a increasing trend not depends on fermenting temperature and they were lower counts than those in Baechu kimchi. Waxy rice paste which added to Chonggak kimchi resulted in increasement of glucose as a carbon source and stimulated to reproduce the microbes in Chonggak kimchi.