• 해양환경안전학회지
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• 제23권7호
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• pp.885-892
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• 2017

2017년 추계에 남해 전선역을 파악하고, 알칼리 인산분해 효소(Alkaline Phosphatase; APase) 활성을 이용하여 제한 영양염과 제한 영양염의 시간적인 변화를 평가하였다. 전선역이 형성된 인근해역의 경우, 용존무기인(dissolved inorganic phosphorus; DIP)의 농도와 용존무기질소(dissolved inorganic nitrogen; DIN): DIP 비가 각각 $0.2{\mu}M$ 이하와 최대 23.2로, DIP가 제한된 환경임에도 불구하고 Chlorophyll a(Chl.-a)가 $0.2{\mu}g/L$로 높은 생물생산력을 보였다. APase와 DIP는 중요한 역의 상관관계(r = -0.81; P<0.001)를 보여, DIP가 제한되어진 해역임을 알 수 있었으며, APase와 Chl-a 관계는 APase의 60 %가 식물플랑크톤, 40 %가 박테리아 기원인 것으로 평가되었다. 용존태 APase와 입자태 APase의 분포로부터 전선역은 장기간 DIP가 제한된 해역이며, 그 외의 해역은 최근에 DIP 제한이 해소된 것으로 판단되었다. 따라서 전선역에서 APase와 같이 가수분해효소의 측정은 제한 영양염의 시공간적인 변화 특성을 평가할 수 있으며, 전선역에서 생지화학 순환의 이해를 높일 수 있을 것으로 생각된다.

• 한국해양학회지:바다
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• 제9권4호
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• pp.153-163
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• 2004

In order to estimate the nutrient flux of the Seomjin River into the coastal waters of South Sea, and to understand the estuarine reactions during mixing between river water and seawater, we collected surface water along the salinity gradient in the Seomjin River estuary from Mar. 1999 to Apr. 2001. We found that nitrate and silicate were delivered by fluvial input, while phosphate was, supplied from disposed wastes in the Gwangyang Bay. Mean annual flux of dissolved inorganic nitrogen (DIN), phosphate and silicate into the Gwangyang Bay was estimated 10.9 molesㆍsec$^{-1}$(4,820 tonnesㆍyr$^{-1}$), 0.07 molesㆍsec$^{-1}$(68 tonnesㆍyr$^{-1}$), 13.3 molesㆍsec$^{-1}$(11,747 tonnesㆍy$^{-1}$), respectively. An evident removal of phosphate, silicate and ammonium at the mid-salinity zone during the dry season was attributed to the active uptake of phytoplankton, and consequently nutrient flux into the Gwangyang Bay was low. Whereas, during the flood season in summer, conservative or additional distribution of the nutrients was observed in the estuary. As a rsult nutrient flux into the Gwangyang Bay was maintained high. High concentrations of chlorophyll a and the active removal of nutrient during the dry season at the mid-salinity zone suggest that nutrient distribution in the Seomjin River estuary was mainly controlled by biological processes and nutrient fluxes into the Gwangyang Bay might be significantly modified of by the primary production.

• Weed & Turfgrass Science
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• 제2권1호
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• pp.82-87
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• 2013

본 연구는 한국잔디의 재배기간 동안 생육 및 무기성분 축적량을 조사하여 한국잔디의 재배전략을 수립하는데 기초자료로 활용하고자 수행하였다. 한국잔디의 경우 다른 작물과 달리 시비와 잔디깎기 등과 같은 관리에 따라 생장 및 무기양분 축적에 차이가 있었다. 잔디깎기로 인해 부위별로 무기양분이 손실되는 양에 비해 축적되는 양이 적었다. 무기양분 축적 차이는 있었으나 K, Ca, Mg은 N과 비슷한 양상을 보였으며, 무기양분의 축적 순서는 N > K > P > Ca > Mg 이었다. 이와 같은 한국잔디의 무기양분 축적 및 흡수특성은 재배의 기초로서 시비량의 결정이나 토양관리 면에서 각 무기양분에 대한 요구성과 서로 밀접한 관계가 있다. 한국잔디의 생육 및 밀도율 향상에 따른 생산량을 늘리기 위해서는 생육시기별 무기양분 축적 파악을 통해 생육시기에 맞추어서 효율적으로 양분을 공급하는 것이 바람직하므로 그에 따른 기초 연구가 필요할 것으로 판단되었다.

• Asian-Australasian Journal of Animal Sciences
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• 제19권1호
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• pp.61-66
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• 2006

This experiment was conducted to evaluate the effects of different selenium (Se) products (inorganic, organic A, organic B) added at two supplemental dietary Se levels (0.1 and 0.3 mg/kg) on growth performance, nutrient digestibility and Se retention in growing-finishing pigs. A $3{\times}2$ factorial arrangement of treatments was used in a RCB design, with a non-Se-fortified basal diet serving as the negative control. A total of 56 crossbred pigs (28 male and 28 female pigs) initially weighing an average $28.45{\pm}0.53kg$ BW were allotted to each treatment with four pigs per pen on the basis of sex and weight. Two pigs per pen were selected and bled from the anterior vena cava at 3- weekly intervals to analyze Se concentration. In the growing phase (0-6 weeks), increased ADFI was observed when pigs were fed organic Se compared to those fed the control diet or inorganic Se treatment (p<0.05). Pigs fed inorganic Se had a great ADFI than pigs fed organic Se (p<0.05) in the late finishing phase (7-12 weeks), although there were no differences in whole period ADFI between organic or inorganic Se products. During 12 weeks of the whole experimental period, serum Se concentration increased linearly when dietary Se level increased regardless of Se products (p<0.05). Both dietary Se source (p<0.05) and Se level (p<0.01) influenced the Se concentration of various pig tissues at end of this experiment and Se content was the highest in the kidney. For the determination of nutrient digestibility, a metabolic trial was conducted in 3 replicates in randomized complete block (RCB) design. A total of 21 barrows ($50.21{\pm}0.62kg$ of average BW) were used in the metabolic study. Selenium supplementation had no effect on nutrient digestibility except for crude protein. Crude protein digestibility increased with dietary supplementation of organic Se (A) compared with other forms of Se products or control diet (p<0.05). Consequently, this experiment indicated that dietary Se products and levels had no effect on growth performance of pigs. Se concentration in tissues and serum was increased in proportion to dietary Se level, especially when organic Se was provided. Although pigs were fed organic forms of Se, bioavailability of organic forms varied among products, consequently bioactivity of organic products to the animals should be evaluated before practical application in animal feed.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.252-261
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• 2006

Four experiments were conducted to investigate the effect of organic or inorganic acid supplementation on the growth performance, nutrient digestibility, intestinal measurements and white blood cell counts of weanling pigs. In growth trial (Exp I), a total of 100 crossbred pigs ({$Landrace{\times}Yorkshire$}${\times}$Duroc), weaned at $23{\pm}2$ days of age and $7.25{\pm}0.10kg$ average initial body weight (BW), were allotted to 5 treatments by body weight and sex in a randomized complete block (RCB) design. Three different organic acids (fumaric [FUA], formic [FOA] or lactic acid [LAA]) and one inorganic acid (hydrochloric acid [SHA]) were supplemented to each treatment diet. Each treatment had 5 replicates with 4 pigs per pen. During 0-3 wk, average daily gain (ADG), average daily feed intake (ADFI) and feed efficiency (G/F ratio) were not significantly different among treatments. However, pigs fed LAA or SHA diet showed improved ADG by 15 or 13% respectively and 12% greater ADFI in both treatments compared to CON diets. Moreover, compared to organic acid treatments, better ADG (p = 0.07) and ADFI (p = 0.09) were observed in SHA diet compared to pigs that were fed the diet containing organic acids (FUA, FOA or LAA). However, during 4-5 wk, no differences in ADG, ADFI and G/F ratio were observed among treatments. Overall, ADG, ADFI and G/F ratio were not affected by acidifier supplementation. Although it showed no significant difference, pigs fed LAA or SHA diets showed numerically higher ADG and ADFI than pigs fed other treatments. In metabolic trial (Exp II), 15 pigs were used to evaluate the effect of acidifier supplementation on nutrient digestibility. The digestibility of dry matter (DM), crude protein (CP), crude fat (CF), crude ash (CA), calcium (Ca) and phosphorus (P) was not improved by acidifier supplementation. Although the amount of fecal-N excretion was not different among treatments, that of urinary-N excretion was reduced in acidsupplemented treatments compared to CON group (p = 0.12). Subsequently, N retention was improved in acid-supplemented groups (p = 0.17). In anatomical trial (Exp III), the pH and $Cl^-$ concentrations of digesta in gastrointestinal (GI) tracts were not affected by acidifier supplementation. No detrimental effect of intestinal and lingual (taste bud) morphology was observed by acidifier supplementation particularly in inorganic acid treatment. In white blood cell assay (Exp IV), 45 pigs were used for measuring white blood cell (WBC) counts. In all pigs after LPS injection, WBC counts had slightly declined at 2 h and kept elevating at 8 h, then returned to baseline by 24 h after injection of lipopolysaccharide (LPS). However, overall WBC counts were not affected by acidifier supplementation. In conclusion, there was no difference between organic and inorganic acidifier supplementation in weanling pigs' diet, however inorganic acidifier might have a beneficial effect on growth performance and N utilization with lower supplementation levels. Furthermore, inorganic acidifier had no negative effect on intestinal measurements and white blood cell counts in weanling pigs. These results suggested that inorganic acidifier might be a good alternative to organic acidifiers in weanling pigs.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.91.2-92
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• 2003

In order to elucidate influence of nutritional status on rice brown spot caused by Cochliobolus miyabeanus, rice cultivation soils and rice straws were collected from paddy fields where ice brown spot occurred severely, moderately, a little and none respectively. Rice plant materials were analyzed to measure inorganic nutrients in rice straws and rice seeds. Analysis of chemical properties of rice paddy soil showed that EC and contents of available phosphate, cation and silicic acid in soil with severe infections were lower than those in healthy soil. This result suggests that amount and holding capacity of nutrient contents in soils collected from paddy field with infection of C. miyabeanus are relatively low compared to those in soils collected from healthy paddy field. Analysis of inorganic nutrients in rice straws showed that amount of macronutrient elements such as silicic acids, available phosphate and total nitrogen, and micronutrients such as copper, iron and zinc in rice straws from paddy field with infection were lower than those in healthy soil. Especially amount of iron and silicic acid were very low in rice straws from paddy field soils with infection Amount of inorganic nutrients such as iron and zinc in rice seeds was the same trend as those of rice straws. These results showed that one of major factors affecting rice brown spot was amount of nutrient contents in soil and rice straw.

• 한국환경과학회지
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• 제13권9호
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• pp.807-817
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• 2004

The modified biochemical oxygen demand (MBOD) were conducted to evaluate the water quality and fertility in the Mangyeong river from november 2002 to april 2003. MBOD method was used to evaluate algal growth potentials and their limiting factors. MBOD depends on the amount of available inorganic nutrient and organic substrate during 5-day incubation in the dark condition at $20^{\circ}C.$ The MBOD assay depends on inorganic nutrients such as phosphorus and nitrogen as well as reduced carbon as called MBOD, MBOD-P, and MBOD-N, respectively. The concentration of pollutants were in the range of 3.08～48.36 mg/L for COD. The concentration of nutrients were in the range of 0.37～111.62 mg/L for dissolved inorganic nitrogen (DIN) and 0.00～1.03 mg/L for dissolved inorganic phosphorus (DIP). The results of MBOD bioassay showed that the MBOD, MBOD-P and MBOD-N values were 15～173 mg $O_2/L,$ 13～165 mg $O_2/L$ and 66～175 mg $O_2/L$ ranges, respectively. The MBOD values are found to be the highest in Iksan River and the lowest in Hari River throughout the Mangyeong River. The relationships of MBOD, MBOD-P and MBOD-N in MBOD method were generally found in MBOD$\risingdotseq$ MBOD-P$\risingdotseq$MBOD-N. But the result of Gosan was appeared to MBOD$\risingdotseq$MBOD-N > MBOD-P. The MBOD-N value was higher 3 to 5 times than the MBOD-P value in the Gosan station. The algal growth potentials expressed as the concentration of chlorophyll-a were maximum 20 times more than algal biomass in the water column.

• 한국해양학회지:바다
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• 제8권2호
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• pp.164-176
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• 2003

하계 진동만에서 얻어진 영양염 DIN(dissolved inorganic nitrogen) 및 DIP(dissolved inorganic phosphate)의 분포는 이들 농도가 만안쪽에서 매우 높은 것이 특징이다. 또 표층(0∼1 m)과 저층(8 m∼bottom)은 만 안쪽이 고농도 이고 중층(1∼8 m)은 상대적으로 낮다. 이러한 영양염의 분포특성을 바람, 조류, 밀도의 수평경도력 및 잔차류를 고려한 생태계모델을 이용하여 조사하였다. 수치실험은 이들 조건들이 영양염에 각기 어떻게 영향을 미치는 가에 주목하여 실시되었다 조석잔차류를 고려한 경우는 전반적으로 관측값보다 저농도의 분포를 보였고, 바람, 조석잔차류 및 밀도의 수평경도력에 의한 효과를 포함한 경우는 보다 관측값에 근접한 결과를 얻었다 이러한 결과는 통계적 분석 방법에서도 잘 뒤받침된다. 본 연구결과는 하계 진동만에서 영양염의 분포변동에 조류효과 뿐만이 아니라 바람에 의한 취송류 및 밀도의 수평경도력에 의해 발생하는 밀도류의 효과가 매우 중요함을 시사한다.

• 한국토양비료학회지
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• 제41권3호
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• pp.158-163
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• 2008

시설재배 수박에 대한 적정 양분함량 기준을 설정하기 위하여 2004년부터 2006년까지 고창에서 시설수박의 엽 중 무기양분함량과 수량을 조사하였다. 그 결과 3년간 조사한 수박 재배 농가 포장을 대상으로 생육단계별 적정 양분함량 범위를 설정하였다. 수박 수량과 생육단계별 엽 중 무기양분함량은 정식후 20일이 가장 유의성 있는 상관을 보였으며 이 때 엽 중 다량원소 적정 함량 범위는 N 5.0~6.3%, P 0.30~0.57%, K 3.5~4.2%, Ca 1.7~3.8%, Mg 0.20~0.42% 이었다. Fe, Mn, Zn, Cu 및 B 등의 미량원소 적정함량 범위는 Fe $96\sim128mg\;kg^{-1}$, Mn $67\sim201mg\;kg^{-1}$, Zn $40\sim60mg\;kg^{-1}$, Cu $6\sim9mg\;kg^{-1}$ 및 B $41{\sim}82mg\;kg^{-1}$ 이었고, 적정 양분함량 범위로 설정한 값의 하한치를 양분 결핍, 상한치를 양분 과잉으로 판단했다. 본 시험연구결과 제시한 수박의 생육단계별 적정 양분함량 범위 기준은 농업현장에서 빈번히 발생하는 수박의 영양장애를 해결하기 위한 양분지표로 사용할 수 있을 것이라 생각된다.

• 한국토양비료학회지
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• 제40권6호
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• pp.471-475
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• 2007

시설재배 멜론에 대한 적정 양분함량 기준을 설정하기 위하여 2004년부터 2006년까지 나주에서 하우스 멜론의 수량 및 잎 중 무기양분함량을 조사하였다. 그 결과 3년간 조사한 멜론 재배 농가 포장을 대상으로 생육단계별 적정 양분함량 범위를 설정하였다. 멜론수량과 관련하여 생육단계별 잎 중 무기양분함량은 정식 후 25일이 가장 유의성 있는 상관을 보였으며 이 때 잎 중 다량원소 적정 범위는 N 3.4~4.8%, P 0.4~0.7%, K 3.4~5.1%, Ca 2.7~4.1%, Mg 0.6~0.8% 이었다. Fe, Mn, Zn, Cu 및 B 등의 미량원소 적정함량 범위는 Fe 102~164, Mn 52~116, Zn 28~98, Cu 7~15 및 B $36{\sim}72mg\;kg^{-1}$ 이었다. 여기에 제시한 멜론의 생육단계별 적정 양분함량 범위 기준은 농업현장에서 빈번히 발생하는 멜론의 영양장애를 해결하기위한 양분지표로 사용할 수 있을 것이다.