• 아시안잔디학회지
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• 제3권2호
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• pp.77-82
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• 1989

This experiment was carried out to determine the value of turfgrass clippings as a source of protein for animal feed. Levels of crude protein(CP) and in vitro dry matter digestibility(JVDMD) were determined for Korean lawngrass (Zoysia Japonica Steud.) under three levels of nitrogen fertilizer ( 0 , 350 and 700kg ha year and three levels of mowing interval between cuts (lO, 20, and 30 days). Sampling was done on the three-year old turffield on which nitrogen and mowing treatments were Imposed. Clippings were collected after mowing, and CP levels were calculated from a measurement of total N(CP = N >< 6.25) l)y Auto-analyser system-2 procedure and IVDMD by Maeng's method which was partly modified with Tilley and Terry's procedure. With the increased nitrogen legime the CP content of leaf clippings varied from 6.6 to 13.6% and that Of stem clippings from 4 to 10.3%. The CP levels of clippings were directly proportional to the N fertilization rate. The highest CP content was recorded in early July when it was 14.1% at 35OkgN ha -and I 18.l%kgN ha-1 with 10-wcek mowing interval. Mowing interval had little effect on the CP content in both leaf and stem clippings. The level of IVDMD in the Korean lawngrass clippings varied with mowing interval. The highest level measured was 47%, hut this varied during the growing season and occurred in the following order : early summer > summer > fall. This experiment has shown that Korean lawngrass clippings can he helpful source of protein for use in some animal feeds and that a high concentration of CP can occur depending upon N fertllizer and that of I VDM I) upon mowing practices.

• 한국토양비료학회지
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• 제46권3호
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• pp.187-192
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• 2013

This study was carried out to investigate the incorporation effect of green manure crops (GMC) such as the hairy vetch on improvement of soil environment in reclaimed land during silage corn cultivation over the past two years. Plots consisted of conventional fertilization (CF) and incorporation of GMC were divided by addition rate of nitrogen fertilizer (100 kg $ha^{-1}$) with 30 - 100% of non nitrogen fertilization (NNF). Soil physico-chemical properties and growth and yield potential of silage corn were examined. The tested soils showed strong alkali and saline properties with low contents of organic matter and available phosphate while contents of exchangeable sodium and magnesium were high. Soil salinity increased during cultivation of summer crop. However, corn was not affected by salt content. The fresh weight of GMC at incorporation time was 18,345 kg $ha^{-1}$. Content of total nitrogen was 3.09% and the C/N ratio was 12.8 at incorporation time. Fresh and dry matter yield of silage corn were higher in the order of N30% reduction, CF, N50% reduction, N70% reduction, N100% reduction and NNF. Fresh and dry matter yield potential of silage corn for N30% reduction were comparable to those of CF. Bulk density of the soil decreased with incorporation of GMC, while porosity was increased. The soil pH decreased while content of exchangeable calcium, available phosphate, and organic matter increased. Also contents of exchangeable sodium and potassium decreased with incorporation of GMC. The data indicate that incorporation of hairy vetch can improve soil physical and chemical properties and reduce nitrogen fertilizer application especially for alkali saline reclaimed soil such as Saemangeum reclaimed land.

• 한국발생생물학회지:발생과생식
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• 제3권1호
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• pp.21-28
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• 1999

흰쥐 난자의 체외수정에 있어서 calcium chelator처리에 따른 피질반응 및 피질과립막의 형성 여부와 피질과립막의 전자현미경적 미세구조를 관찰하고, 수정율 및 단정자수정과 다정자수정 빈도에 미치는 영향을 조사하여 수정기간중 calcium의 역할을 조사하였다. Calcium chelator로는 BAPTA/AM을 사용하였으며, 난자의 미세구조와 피질과립막은 주사전자현미경으로 관찰하였다. 투명대가 제거된 난자의 체외수정 과정에서는 피질반응에 의해 형성된 피질과립막 (cortical granule envelope)이 관찰되었고, calcium chelator (1, 5, 10, $\mu$M BAPTA/AM) 처리후 투명대가 제거 된 난자의 체외수정 에서도 마찬가지로 피질과립막이 관찰되었다. 또한 체외 수정 후 시간의 경과에 따라 피질과립막은 좀 더 발달되는 양상을 나타내었다. 수정율은 calcium chelator 처리군 (59.8, 38.1, 37.0%)이 대조군 (60.6%)에 비해 감소했으나, 단정자수정은 calcium chelator 처리군 (45.0, 47.3, 50.9%)이 대조군 (37.5%)에 비해 증가하였다. 위의 결과들로부터 흰쥐에서 수정시 피질과립막이 형성된다는 것을 밝혔고, 피질반응에 extracellular calcium이 이용됨을 알 수 있다. 또한 난자내의 적정한 free calcium 함량이 수정에 중요한 요인으로 작용하는 것으로 사료된다.

• 한국토양비료학회지
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• 제32권3호
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• pp.254-260
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• 1999

본 연구(硏究)는 호남평야지(湖南平野池) 논토양(土壤)의 대표토양(代表土壤)인 전북통(全北統)에서 벼 무논골뿌림직파물리성개선(直播物理性改善) 및 진단시비(診斷施肥)에 의한 쌀 안정(安定) 증수방법(增收方法)을 구명(究明)하고자 관행(慣行), 진단시비(診斷施肥), 진단시비(診斷施肥)+심경(深耕), 심토파쇄(心土破碎), 진단시비(診斷施肥)(LCU80%) + 심토파쇄(深土破碎), 무질소구(無窒素區) 등(等) 6처리(處理)로 하여 2년간(年間)('97~'98)에 걸쳐 검토(檢討)한 시험결과(試驗結果)를 요약(要約)하면 다음과 같다. 심경(深耕) 및 심토파쇄시(心土破碎時) 관행(慣行)에 비하여 경도(硬度), 용적밀도(容積密度)가 낮아지고 공극률(孔隙率)이 증가(增加)하여 물리성(物理性) 개선효과(改善效果)가 현저하였으며 화학성분중(化學成分中) 유기물(有機物), 인산(燐酸), 가리함량(加里含量)이 크게 증가(增加)하였다. 시비질소(施肥窒素)의 토양중(土壤中) $NH_4-N$ 용출량(溶出量)은 관행대비(慣行對比) 진단시비(診斷施肥) + 사양물리성개선구(士壤物理性改善區)에서 크게 증가(增加)하였으며, 시비질소(施肥窒素)의 흡수량(吸收量)과 이용률(利用率)은 진단시비(診斷施肥)(LCU80% 전량기비(全量基肥))+심토파쇄구(心土破碎區)에서 가장 많았으며 엽색(葉色)과 경엽중(莖葉中) 질소농도(窒素濃度)는 관행(慣行)에 비하여 진단시비(診斷施肥)+토양특리성개선구(土壤特理性改善區)에서 최고분벽기(最高分蘗期)부터 출수기(出穗期)기까지 높았으며 이들 상호간(相互間)의 유의성(有意性)이 인정(認定)되었다. 쌀수량(收量)은 관행(慣行)보다 진단시비(診斷施肥) 6%, 진단시비(診斷施肥) + 심경구(深耕區) 18%가 증수(增收)하였으나 진단시비(診斷施肥)(LCU80% 전량기비(全量基肥))+심토파쇄구(心土破碎區)에서 23%가 증수(增收)되었고 시비효율(施肥效率)도 가장 높았다.

• 한국어류학회지
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• 제31권3호
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• pp.131-140
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• 2019

본 연구는 난과 자치어의 형태 및 생활사가 밝혀지지 않은 G. strigatus의 초기생활사에 대하여 연구하였다. G. strigatus의 친어는 경기도 남양주시의 왕숙천에서 확보하였다. 성숙된 암컷 친어에 HCG (human chorionic gonadotropin)를 10 IU/g의 농도로 주사하여 성숙란을 얻었으며, 습식법으로 인공 수정하였다. 수정란은 불투명한 흰색 원형의 침성점착란으로 직경은 1.66~1.88 mm이었다. 수정란은 수온 $23{\pm}1^{\circ}C$에서 수정 54시간 후 부화가 완료되었으며, 부화자어의 전장은 4.1~4.7 mm로 무색투명하였다. 부화 4일 후 자어는 5.4~5.9 mm로 입과 항문이 열리고 알테미아를 섭식하여 전기자어기로 이행하였다. 부화 10일 후 자어는 7.5~8.6 mm로 척삭말단이 굴곡되고 꼬리지느러미의 기조가 형성되어 중기자어기로 이행하였다. 부화 16일 후 자어는 8.2~9.7 mm로 척색말단의 굴곡이 완료되었고 부레가 두 개로 분할되어 후기자어기로 이행하였다. 부화 38일 후 모든 지느러미의 기조가 정수에 도달하여 치어단계로 이행하였다.

• 한국작물학회지
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• 제37권4호
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• pp.329-334
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• 1992

남부지방의 결명자 재배 체계 확립을 위한 기초자료를 얻고자 비닐 피복과 무피복재배 상태에서 시비량 차이에 따른 생육과 수량의 특성을 검토한 결과는 다음과 같다. 1. 경장, 경직경, 분지수, 1주협수, 협장, 1협립수 등의 모든 형질이 비닐 피복구에서 우수하였으며 이들 생육특성 중에서 경직경, 1주협수, 1협립수 등의 형질은 N-P$_2$O$_{5}$-K$_2$O=8-6-6Kg /10a 구에서 가장 우수하였고 경장, 분권수, 협장은 N-P$_2$O$_{5}$-K$_2$O=8-6-6Kg /10a와 N-P$_2$O$_{5}$-K$_2$O=16-12-12Kg /10a구에서 가장 우수하였다. 2. 천립중과 종실수량 역시 비닐 피복구에서 높았으며 시비량 N-P$_2$O$_{5}$-K$_2$O=8-6-6Kg / 10a구를 기점으로 이보다 감비하거나 증비한 구는 감수하는 경향이었다. 3. 비닐 피복과 무피복 아래에서 시비량 차이에 따른 유용 형질들의 분산분석에서도 유의성이 인정되었다.

• 한국초지조사료학회지
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• 제11권2호
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• pp.97-101
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• 1991

This experiment was carried out to determine the effect of pure mineral nitrogen fertilization on dry matter yield and the amounts of advisable mineral nitrogen on grassland according to its age at the "Federal Institue for Agriculture in the Alps" in Austria. The results obtained were as follows: 1. With only PK-fertilizing average dry matter yields per year were progressively declined during the period of the studies. Compared with the relatively younger grassland(1st-5th year) the DM-yields were decreased by 35% in older grassland (11th-final year). 2. Due to the less reduction of DM-yields by mineral nitrogen application according to the age of grassland. With N-fertilizing the reduction of DM-yields in relatively older grassland was less than that of younger grassland by 11-21%. 3. At 4-and 5-cut systems the nitrogen amounts for the highest marginal yield(the "most efficient" Ndressing rate) per ha and year were distinctly declined in the relatively older grassland. 4. Required efficiencies of mineral nitrogen were not influenced by the age of grassland.he age of grassland.

• 수산해양기술연구
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• 제51권3호
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• pp.370-374
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• 2015

Pacific herring Clupea pallasii eggs were attached to the gill net in Korean coastal waters off Busan. To conservation and management the eggs attached to the gill net, we followed the natural hatching in coastal waters from five days after fertilization to the hatching finished, where the temperature was $9^{\circ}C$. The diameter of fertilized eggs was 1.24-1.55 mm (n= 50), and had a segmented pale yellow yolk, no oil globule. Natural hatching had started by 10 days after fertilization. Mass hatching occurred around 11-12 days after fertilization, most of eggs separated from the gill net. Therefore, when the Pacific herring eggs attached in gill net, should be natural hatching-induced in coastal waters during 12-14 days.

• 한국농공학회지
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• 제42권3호
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• pp.66-75
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• 2000

Effect of reclaimed sewage on the paddy rice culture was examined by field experiment for two consecutive years. The domestic sewage was treated by the constructed wetland and the effluent of the treatment wetland was used for irrigation water. The reclaimed sewage was diluted before irrigation in the first year and it was used without dilution in the second year experiment. Growth components and yields were compared against the control plot where conventional method was applied. And also soil characteristics of the plots before and after reclaimed sewage irrigation were analyzed Generally addition of the reclaimed sewage irrigation didn't affect paddy rice culture adversely and even enhancement was observed. Fertilization was thought to be important factor for rice culture rather than irrigation water quality. Conventional fertilization and reclaimed sewage irrigation which contained high nutrient concentration resulted in better growth and more yield. Unlike widespread concern lodging did not happen even in the case of irrigation with average 90mg/L of T-N and conventional fertilization. Soil characteristics changed after irrigation and significant EC increasing was observed for the reclaimed sewage irrigation plots. From soil analyses salt accumulation could be a more potential problem than nutrients like nitrogen and phosphorus in the use of reclaimed sewage irrigation. Overall reclaimed sewage irrigation was thought to be one of practical alternatives for the ultimate disposal of sewage in rural area.

• 한국토양비료학회지
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• 제46권3호
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• pp.223-229
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• 2013

Sustainability index was calculated to determine the best management for rice productivity under long-term inorganic fertilizer management's practices. It is based on nutrient index, microbiological index and crop index related to sustainability as soil function. Indicators for calculating sustainability index were selected by the comparison of soil properties and rice response in paddy soil with fertilization. Total twenty two indicators were determined to assess nutrient index, microbiological index and crop index in order to compare the effect of different fertilization. The indices were applied to assess the sustainability with different inorganic fertilizer treatments such as control, N, NK, NP, NPK, NPK+Si, and NPK+Compost. The long-term application of compost with NPK was the highest sustainability index value because it increased nutrient index, microbial index and crop index. The use of chemical fertilizers resulted in poor soil microbial index and crop index, but the treatments like NP, NPK, and NPK+Si were maintained sustainability in paddy soil. These results indicate that application of organic and chemical fertilizer could be a good management to improve rice sustainability in paddy soil.