• 제목/요약/키워드: summer fallow

검색결과 14건 처리시간 0.018초

겨울논 유채와 보리 재배시 전과정평가 방법을 이용한 환경영향 비교 평가 (Comparative Evaluation for Environmental Impact of Rapeseed and Barley Cultivation in Paddy Field for Winter using Life Cycle Assessment)

  • 홍승길;신중두;박광래;안민실;옥용식;김정규;김석철
    • 유기물자원화
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    • 제24권4호
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    • pp.59-68
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    • 2016
  • 벼 수확 후 겨울철 휴경논에서 유채 재배 시스템의 환경영향을 평가하고 경쟁 작물인 보리 재배 시스템의 환경영향과 비교 분석하기 위하여 전과정 평가방법을 적용하였다. 투입물질에 대한 자료를 수집하고 유채 및 보리 1 ton을 기능단위로 하여 분석하였다. 전과정 영향평가를 위해서는 체계화가 잘 되어있고 규칙적으로 적용된 영향평가 방법인 Eco-indicator 95 방법을 사용하였다. 생산물 1 ton당 발생하는 영향범주별 비교에서는 온실가스 등 6개 영향범주에서 보리보다 유채의 포텐셜이 높게 나타났는데 이 중 화학비료 사용에 의한 환경부하가 전체 발생량의 65-96%를 차지하고 있었다. 부영양화 포텐셜은 오히려 유채보다 보리에서 높게 나타났다. 보리와 유채 재배에서 중금속에 의한 부하가 0.5 Pt로 상대적으로 가장 크게 나타났으나 전체 영향범주값을 합산하게 되면 보리에서 0.78 Pt, 유채에서 0.82 Pt로 나타났다. 시비-수확량 반응 시험에 대한 평가에서 보리는 시비량이 증가할수록 환경부하가 계속 증가하는 것으로 나타났으나 유채는 시비량에 따라 증가하다가 최고 생산량을 보인 R3(80-65-65)에서는 오히려 감소하였다. 이와 같은 결과를 토대로 겨울 휴경논에 유채를 재배할 경우 환경 영향 범주 8개 중 6개 범주에서 기존의 보리를 재배하는 과정에 비해 환경부하량은 더 크다고 할 수 있지만 환경지수값으로 환산하게 되면 휴경지에서 유채와 보리 재배를 통한 환경영향에는 차이가 없을 것으로 판단되었다.

느타리버섯 재배에서 버섯파리의 연중발생패턴과 입체적 분포 (Annual Occurrence Patterns and Three Dimensional Distribution of Mushroom Flies in Pleurotus ostreatus Cultivation Farms)

  • 강민구;김승한;최치완;헨리디즈니;권오석
    • 한국응용곤충학회지
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    • 제56권2호
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    • pp.213-222
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    • 2017
  • 최근 느타리버섯은 연중재배가 보편화되고 있으며, 재배량도 급격히 증가하고 있는 추세이다. 경북지역 느타리버섯 재배사에서 3년에 걸쳐 버섯파리 발생밀도를 조사한 결과 긴수염버섯파리와 버섯벼룩파리가 가장 우점하여 발생하였다. 일반적으로 균사배양기간에는 버섯파리 밀도가 모든 농가에서 낮았지만 1주기 수확후에는 급격히 증가하는 경향을 보였다. 하지만, 여름철에는 배양기간임에도 불구하고 많은 버섯파리가 관찰되었다. 이 현상은 연중재배체계의 보편화로 인해 계절적 선택재배와 달리 버섯파리가 재배사에서 안전하게 월동할 수 있는 서식처를 제공받았기 때문이다. 버섯파리의 생태는 버섯재배환경에 따라 달라질 수 있다. 계절적 선택재배농가와 연중재배농가의 버섯파리 발생패턴 차이를 통해 휴경이 버섯파리 발생밀도 감소에 중요한 역할을 한다는 것을 확인하였다. 버섯재배사 내부의 버섯파리 입체발생분포 조사를 통해 긴수염버섯파리보다 버섯벼룩파리가 빛에 더 민감한 종임을 확인하였다. 또한 2종의 입체적 발생양상은 매우 차이가 있는 것을 확인하였다.

Nitrogen fixation, and growth characteristics of Three Legume cover crops in no-tillage paddy field

  • Cho, Young-Son
    • 한국작물학회지
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    • 제48권4호
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    • pp.308-315
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    • 2003
  • A field experiment was conducted to investigate the performance of three legume species in a zero-tillage, non-fertilized rice field in a temperate zone. Before the experiment for 5 years, from 1995 to 1999, plant growth patterns of three legume species grown as over-wintering (October-May) cover crops on a paddy field were maintained to study N balance and $\textrm{N}_2$ fixation. Decrease in plant density accelerated from after winter to flowering from 1,090, 320, and 5 to 732, 232, and 6 plants $\textrm{m}^{-2}$ in Chinese milk vetch (CMV), white clover (WC), and hairy vetch (HV), respectively. Total dry weights of plants above-ground level were 0.05, 0.11, and 2.43 g $\textrm{plant}^{-1}$. in WC, CMV and HV respectively but steeply increased at ripening up to 0.77, 2.33, and 26 g $\textrm{plant}^{-1}$. The root dry weight of HV and CMV rapidly increased while in WC, root dry weight increased slightly towards flowering. The highest nodule numbers were recorded in CMV to April thereafter WC produced the highest. Nodule size was distributed within 7mm in CMV but it was larger in HV varying from 1 to 10mm. Shoot N (g $\textrm{m}^{-2}$) greatly increased from over-wintering to flowering in CMV, HV and WC and it ranged from 1.66, 0.5 and 1.92 to 12.6, 3.1 and 13.02 g $\textrm{m}^{-2}$, respectively. After wintering, the initial shoot N content (%) was more in CMV. Root N content (%) was constant or slightly decreased in HV and WC. Soil total N in the control plot (clean fallow) was the highest on Mar. 2 then decreased rapidly to flowering. Soil N content was constant in HV plots whereas it was low in WC plots for the entire growth period except just after winter. Maximum nitrogenase activities were 9, 37.8, and 131 mol $\textrm{C}_2\textrm{H}_4$ $\textrm{plant}^{-1}$ $\textrm{hour}^{-1}$. in CMV, HV, and WC, respectively. Nitrogenase activity showed a direct correlation with nodule number, size and fresh weight. As a cover crop preceding a rice crop, CMV is more suited to colder regions due to its earlier ripening characteristics. Hairy vetch and WC are recommended for regions with a mild winter and a long summer owing to their late ripening and great N fixation activity.

Review of the Current Forage Production, Supply, and Quality Measure Standard in South Korea

  • Kim, Jong Duk;Seo, Myeongchon;Lee, Sang Cheol;Han, Kun-Jun
    • 한국초지조사료학회지
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    • 제40권3호
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    • pp.149-155
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    • 2020
  • Cattle feeding in South Korea has been heavily dependent on domestically produced rice straw and imported grain. Around 42% of domestically produced rice straw is utilized for forage, and the remainder is recycled to restore soil fertility. Approximately 35% of round baleages were made with rice straw. However, higher quality hay is desired over rice straw. Due to increasing stockpiles of rice, there has been an economic burden on the government to store the surplus; therefore production of annual forage crops in rice fields has been further promoted in recent years. Hay import from the USA currently constitutes more than 80% of total imported hays. The main imported hays are alfalfa (Medicago sativa), timothy (Phleum pretense), and tall fescue (Festica arundinacea). The estimated forage required for cattle feeding was approximately 5.4 million MT in 2016. Domestically produced forage sates only 43% of that value, while low quality rice straw and imported hay covered the rest of demand by 33% and 20%, respectively. As utilization of domestically produced forage is more desirable for forage-based cattle production, long-term strategies have been necessary to promote domestic production of high quality baleage. One such strategy has been utilizing the fertile soil and abundance of fallow rice fields of western region of S. Korea to produce forage crops. Italian ryegrass (Lolium multiflorum) is the most successfully produced winter annual in the region and is approximately 56% of the total winter annual forage production. Forage sorghums (Sorghum bicolor), sorghum × sudangrass hybrids, and hybrid corn (Zea mays) produce a substantial amount of warm-season forage during summer. Produced forage has been largely stored through baleage due to heavy dew and frequent rains and has been evaluated according to S. Korea's newly implemented baleage commodity evaluation system. The system weighs 50% of its total grading points on moisture content because of its importance in deliverable DM content and desirable baleage fermentation; this has proved to be an effective method. Although further improvement is required for the future of forage production in South Korea, the current government-led forage production in rice fields has been able to alleviate some of the country's shortage for quality hay.