• 한국토양비료학회지
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• 제17권4호
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• pp.381-388
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• 1984

객토원(客土源)을 구(求)하기 어려운 평야지(平野地) 사질답(砂質畓)의 토양개량제(土壤改良劑)로서 객토대체자원(客土代替資源)으로 Zeolite 시용(施用)의 가능성(可能性)을 검토(檢討)하기 위하여 포장시험(圃場試驗)과 실내시험(室內試驗) 결과(結果)를 요약(要約)하면 다음과 같다. 1. 점토함량(粘土含量) 16%인 토양(土壤)에 규산(珪酸)을 적량시용(適量施用)하고 질소(窒素)를 흡착(吸着)시킨 Zeolite 시용(施用)은 벼 생육(生育) 및 수량(收量)에 있어 객토(客土) 40M/T/10a 시용(施用)과 동등(同等)한 효과(效果)가 인정(認定)되었다. 2. 최고수량(最高收量)을 낸 질소시용량(窒素施用量)은 무개량구(無改良區), 객토(客土), Zeolite구(區)에서 각각(各各) 15.0, 18.2, 18.1kg/10a 이었다. 3. 객토구(客土區)와 Zeolite구(區)에서 수확기(收穫期) 질소(窒素) 및 $SiO_2$, 흡수량(吸收量)이 무개량구(無改良區)에 비(比)해 현저(顯著)히 많았다. 4. 토양(土壤), 객토원(客土源) 및 Zeolite의 암모늄 흡착양상(吸着樣相)은 Langmuir 등(等) 온흡착식(溫吸着式)을 따랐고 암모늄 최대흡착(最大吸着)은 각각(各各) 16.7, 20.5, 890mg/10a이었다.

• 한국토양비료학회지
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• 제45권1호
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• pp.86-92
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• 2012

To promote the practical use of livestock manure compost (LC) for paddy rice cultivation, the fertilization efficiency of nutrients in LCs was investigated compared to that of chemical fertilizer. This experiment was conducted at rice field in Hwaseong, Korea, with 6 treatments by each of 3 kinds of tested LCs, cattle manure compost (CaC), swine manure compost (SwC) and chicken manure compost (ChC). The treatments consisted of 3 application levels of LCs and 3 chemical fertilizer treatments having the same application levels with LCs. $NH_4$-N content in soil became higher according to the increase in the urea application rate, while it became lower in LC plots than in urea plots, and statistically had no significant difference among LC plots. There was a close relationship between phosphate fertilization rate and the increment of soil available phosphate content after experiment resulting y = 0.1788x - 6.169 ($R^2=0.9425$) when applied fused superphosphate fertilizer, and y = 0.0662x - 2.689 ($R^2=0.9315$) when applied LC at the equivalent rates to phosphate input (x: phosphate application rate, kg $ha^{-1}$, y: increment in soil available phosphate content, mg $kg^{-1}$). And from these two equations, the correlation on the phosphate application rate between fused superphosphate fertilizer and LC could be obtained as y = 2.7056x - 52.492 (x: $P_2O_5$ application rate of fused superphosphate, kg $ha^{-1}$, y: $P_2O_5$ application rate of LC, kg $ha^{-1}$). Plant height, number of tillers, nutrients uptake by rice, and rice yield showed higher levels in N 100% and N 150% application plots of chemical fertilizers, while every LC plots exhibited lower values and no significant difference among them. Relative nitrogen fertilization efficiencies of LCs compared to urea was 12.3% for CaC, 8.8 for SwC and 24.6 for ChC, respectively.

• 한국토양비료학회지
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• 제47권6호
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• pp.553-557
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• 2014

The steady increase in livestock industry has greatly required the stable production of food and forage crops. As an alternative, rice-forage cropping system has been attempted in several southern areas. The present study was performed to understand whether an application of cattle-manure compost affects soil chemical properties and crop productivity in rice-forage cropping system, rice ${\rightarrow}$ summer oat ${\rightarrow}$ rye, in Jangheong county, south Jeolla province from 2013 to 2014. Treatments was composed of control (no compost), CM1 (compost application before rice transplanting), and CM2 (two-times compost application, before rice transplanting and after rice harvest), and inorganic fertilizers (N, P, and K) were equally dressed in all plots. Yields of rice were not significantly different between treatments, however, oat production was 1.25-fold higher in CM1 and CM2. Nutrient uptake amounts of rye were higher in CM2 than CM1 and control. Total nitrogen in soil was maintained stable level during crop cultivation. And soil organic matter contents in all treatments were increased by crop residue. Available P_2O_5$ and exchangeable K were increased by cattle manure application. Therefore, it suggested that the amount of nutrient by forage crop residue should be considered in rice-forage multiple cultivation.

• 한국물환경학회지
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• 제28권1호
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• pp.10-17
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• 2012

The middle and lower reaches of the Kum River system become stagnant in dry seasons with florishing of phytoplankton. In this study primary productivity of phytoplankton were measured by the C-14 uptake method and the P-I model method at seven main stream sites of the Kum River from the Daechung Dam outet to the river mouth. Nutrients (TN, TP, DIP, TIN) concentrations were measured in the mainstream and tributaries and compared with the variation of assimilation number. The range of primary productivity was $40{\sim}4,558mgC{\cdot}m^{-2}{\cdot}day^{-1}$ and it was higher than those of lentic ecosystems in Korea. Average TN and TP were $4.1mgN{\cdot}L^{-1}$, $70.6mgP{\cdot}m^{-3}$, respectively. Tributaries showed higher nutrient concentrations than the main stream. After two major tributaries merged with the discharging water of the Daechung Dam phyotplankton biomass and productivity increased drastically and remained at the similar eutrophic level through the downstream reach to the river mouth. Both dissolved phosphorus and nitrogen concentrations showed positive correlation with assimilation number of phytoplankton. In conclusion phytoplankton productivity is at the level of eutrophic water and it was higher than usual lentic habitats. Nutrient concentrations are critical factors in controlling productivity in the lower reach of the Kum River.

• 한국환경보건학회지
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• 제22권2호
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• pp.90-95
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• 1996

This study was performed to calculate the degration rate coefficient, operating parameters to meet the effluent standards, and the temperature adjustment coefficients to each parameter of pollution by seasonal variation of concentration and temperature of influent in livestock wastewater treatment by sequencing batch reactor process in field scale. The followings are the conclusions that were derived from this study. 1. In the field, temperature of livestock wastewater in reactor was 20.3$\circ$C in summer and 6.0$\circ$C in winter. The ratio of BOD:TKN: T-P in influent was 100:80:7. BOD loadings in winter and spring were 0.26 and 0.43 kg $BOD/m^3$ day, respectively. Those in summer and fall were 0.25 and 0.13 kg $BOD/m^3$ day, respectively. 2. The degradation rate coefficient for TKN was larger in summer and fall in which temperature was high than that in which temperature was high than that in winter and spring in which concentration was high. On the contrary, the phosphorus uptake rate was larger in winter and spring than that in summer and fall. 3. The hydraulic retention time in winter and spring was longer than that in summer and fall. Especially, in order to meet the standard for TKN of 120 mg/l in winter in which temperature of wastewater was 6.0$\circ$C, as the MLSS concentration was increased from 4, 000 to 7, 000 mg/l, the hydraulic retention time was increased from 212 to 121 hours. But, in order to shorten that less than 121 hours for the economical wastewater treatment, countermeasure to increase temperature of wastewater in the reactor should be considered. 4. the temperature adjustment coefficients for BOD, $COD_{Mn}$, TKN and T-P were 1.0241, 1.0225, 1.0541 and 1.0495, respectively. Namely, the treatment of TKN was most sensitively affected by temperature. For the purpose of the effective removal of nitrogen and phosphorus which are sensitive to temperature, it is necessary to keep the temperature of livestock wastewater more than 20$\circ$C which is the temperature of it in summer.

• Ocean and Polar Research
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• 제30권4호
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• pp.407-418
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• 2008

Seawater samples were collected at discrete depths from five stations across the polar front in the Drake Passage (Antarctic Ocean) by the $20^{th}$ Korea Antarctic Research Program in December, 2006. Nitrate concentrations of seawater increase with depth within the photic zone above the depth of Upper Circumpolar Deep Water (UCDW). In contrast, ${\delta}^{15}N$ values of seawater nitrate decrease with depth, showing a mirror image to the nitrate variation. Such a distinct vertical variation is mainly attributed to the degree of nitrate assimilation by phytoplankton as well as organic matter degradation of sinking particles within the surface layer. The preferential $^{14}{NO_3}^-$ assimilation by the phytoplankton causes $^{15}{NO_3}^-$ concentration to become high in a closedsystem surface-water environment during the primary production, whereas more $^{14}{NO_3}^-$ is added to the seawater during the degradation of sinking organic particles. The water-mass mixing seems to play an important role in the alteration of ${\delta}^{15}N$ values in the deep layer below the UCDW. Across the polar front, nitrate concentrations of surface seawater decrease and corresponding ${\delta}^{15}N$ values increase northward, which is likely due to the degree of nitrate utilization during the primary production. Based on the Rayleigh model, the calculated ${\varepsilon}$ (isotope effect of nitrate uptake) values between 4.0%o and 5.8%o were validated by the previously reported data, although the preformed ${\delta}^{15}{{NO_3}^-}_{initial}$ value of UCDW is important in the calculation of ${\varepsilon}$ values.

• 한국토양비료학회지
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• 제23권3호
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• pp.199-203
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• 1990

1. pH가 6.4인 상토(床土)에 복비시제품(複肥試製品) 시용(施用)으로 생육기간중(生育期間中)의 상토(床土) pH가 4.0~5.4로 유지(維持)되었다. 2. 복비시제품구(複肥試製品區)의 묘생육상황(苗生育狀況)은 단비구(單肥區)에 비(比)하여 건물중(乾物重)과 엽수(葉數)가 많았으며 건물중(乾物重)/초장비(草長比)도 높았고, 묘립고병(苗立枯病)의 발생률(發生率)도 적었다. 3. 묘(苗)의 무기성함량(無機成分含量)은 생육기간(生育初期)에는 단비구(單肥區)에 비하여 복비시제품구(複肥試製品區)가 다소 낮았으나 생육후기(生育後期)에는 높은 경향(傾向)이었다. 4. 복비시제품(複肥試製品)을 1회(回) 전량기비(全量基肥)로 시용(施用)하여 성력재배(省力化栽培)가 가능(可能)하였고, 건묘(健苗)를 육성(育成)할 수 있었다.

• 한국토양비료학회지
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• 제23권2호
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• pp.128-134
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• 1990

예산읍내의 중요시설채소재배지 세부락을 중심으로 작부양식, 시비방법, 토양화학성, 작물의 영양상태와 생육상황을 조사하였다. 토마토의 시듦병 은 토양의 높은 EC와 질소함량 그리고 뿌리흑선충과 밀접하게 관련된것 같다. 칼슘결핍은 토양의 높은 K와 EC 그리고 토마토의 높은 철흡수에 기인하는것 같다. 여름배추는 80%의 생육억제를 보였는데 높은 EC(1.8mmho/cm) 때문이며 근류병(무사마귀명)을 보였는데 토양의 높은 인산함량(1,055 ppm) 때문인것 같다. 열무는 50%의 생육저하를 보였는데 높은 EC(1.6 mmho/cm), K 및 Mg 그리고 염기의 불균형때문으로 보인다. 다섯가지의 복합비료가 기비로 사용되고 질소칼리의 한가지 복비는 염화킬리 및 뇨소와 같이 추비로 사용하였다. 가축분의 다량사용과 매 적부시의 화학비료 다량 사용은 심토까지 과부화를 시켰다.

• 한국토양비료학회지
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• 제45권6호
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• pp.910-919
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• 2012

The role of inorganic nitrogen assimilation in the production of amino acids, organic acids and soluble sugars is one of the most important biochemical processes in plants, and, in order to achieve normally, nitrate uptake and assimilation is essential. For this reason, the characterization of nitrate assimilation and metabolite composition from leaves, roots and xylem sap of tomato (Solanum lycopersicum) was investigated under different nitrate levels in media. Tomato plants were grown hydroponically in liquid culture under five different nitrate regimes: deficient (0.25 and 0.75 mM $NO_3{^-}$), normal (2.5 mM $NO_3{^-}$) and excessive (5.0 and 10.0 mM $NO_3{^-}$). All samples, leaves, roots and xylem sap, were collected after 7 and 14 days after treatment. The levels of amino acids, soluble sugars and organic acids were significantly decreased by N-deficiency whereas, interestingly, they remained higher in xylem sap as compared with N-normal and -surplus. The N-excessive condition did not exert any significant changes in metabolites composition, and thus their levels were similar with N-normal. The gene expression and enzyme activity of nitrate reductase (NR), nitrite reductase (NIR) and glutamine synthetase (GS) were greatly influenced by nitrate. The data presented here suggest that metabolites, as a signal messenger, existed in xylem sap seem to play a crucial role to acquire nitrate, and, in addition, an increase in ${\alpha}$-ketoglutarate pathway-derived amino acids under N-deficiency may help to better understand plant C/N metabolism.

• 한국작물학회지
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• 제39권6호
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• pp.556-563
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• 1994

작물의 영양생장기에 처리된 산성비에 대한 내성과 피해양상을 알기 위하여 벼, 옥수수, 콩, 팥, 고추, 토마토, 참깨, 밀, 보리, 배추, 무, 상추, 시금치 등 13개 작물을 파종 후 20일에 인공산성비 (pH 3.0, 4.5, 6.0)를 10mm씩 2일 간격으로 15회 처리한 후 작물의 형태적 및 생리적 변화를 조사분석한 결과를 요약하면 다음과 같다. 1. pH가 3.0이상일 때 인공산성비 처리에 의한 가시적 피해는 없었다. 2. 전자현미경상 조직의 피해는 없었으나 참깨, 콩, 팥의 엽록체내에 염색정도가 옅은 지질과립이 나타났다. 3. 엽신의 엽록소 함량은 팥에서는 증가하였으나, 벼, 토마토, 시금치에서는 감소되었고, 다른 작물은 인공산성비 처리간에 차이가 없었다. 4. 광합성은 팥에서 증가되었고, 배추와 보리에서는 감소하였으나 다른 작물은 인공산성비의 영향이 없었다. 5. pH 2.0의 인공산성비를 처리하였을 때 가시적 피해가 적은 작물은 벼, 옥수수, 참깨, 토마토, 밀, 보리 등이었으며, 피해가 큰 작물은 팥, 고추, 콩, 배추, 상추, 무, 시금치 등이었다.