• 한국토양비료학회지
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• 제44권1호
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• pp.146-159
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• 2011

The continuous increase in the production of metals and their subsequent release into the environment has lead to increased concentration of these elements in agricultural soils. Because microbes are involved in almost every chemical transformations taking place in the soil, considerable attention has been given to assessing their responses to metal contaminants. Short-term and long-term exposures to toxic metals have been shown to reduce microbial diversity, biomass and activities in the soil. Several studies show that microbial parameters like basal respiration, metabolic quotient, and enzymatic activities, including those of oxidoreductases and those involved in the cycle of C, N, P and other elements, exhibit sensitivity to soil metal concentrations. These have been therefore, regarded as good indices for assessing the impact of metal contaminants to the soil. Metal contamination has also been extensively shown to decrease species diversity and cause shifts in microbial community structure. Biochemical and molecular techniques that are currently being employed to detect these changes are continuously challenged by several limiting factors, although showing some degree of sensitivity and efficiency. Variations and inconsistencies in the responses of bioindicators to metal stress in the soil can also be explained by differences in bioavailability of the metal to the microorganisms. This, in turn, is influenced by soil characteristics such as CEC, pH, soil particles and other factors. Therefore, aside from selecting the appropriate techniques to better understand microbial responses to metals, it is also important to understand the prevalent environmental conditions that interplay to bring about observed changes in any given soil parameter.

• 한국환경농학회지
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• 제27권4호
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• pp.456-459
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• 2008

Quality of rice grain changes during dry storage with internal physiological changes and external injury by organism. Storage rice changes by condition with respiration via variable temperature, hydrolysis enzyme reaction, lipid peroxidation occurs with change of palatability. During dry storage, physiological change with protein variation pattern was examined by image analysis on proteomic technology. Analysis revealed that protein activity had no change store at room temperature and store at $40^{\circ}C$, but decreased store at $60^{\circ}C$. Analysis of variable hydrophobic protein pattern revealed that protein activity of beta-tubulin, protein disulfide isomerase, vacuolar ATPase b subunit, globulin was not significantly decreased all dry and store condition. However, heat shock protein 70, and glutathione transferase was significantly decreased when rice dried at $60^{\circ}C$ compared with room temperature and $40^{\circ}C$ dry condition.

• 한국작물학회지
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• 제23권3호
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• pp.5-11
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• 1978

Since 1970, herbicides have been widely used in the crop production, especially in paddy field in Korea. In 1978, both preemergence and postemergence type herbicides are applied in the approximately 70% of total paddy field and 15% of upland to control weeds. Most herbicides control annual weeds effectively, but perennials have been problems in the paddy field. Under upland conditions, effectiveness of herbicides varies depending on many environmental conditions (soil moisture, soil physical properties, temperature, etc.) as well as uniform application of appropriate amounts of herbicides. In Korea, many research works have been concentrated on the screening of new herbicides in terms of herbicide effectiveness and yield or phytotoxicity of crops, and especially on the paddy field. However, physiological aspects of herbicidal action in plant and interaction of herbicides with the environments have not been studied approximately. Therefore, researches on the uptake of herbicides and the influence of herbicides on the physiological phenomena such as photosynthesis, respiration, nutrient uptake etc., to control troublesome perennial weeds in the paddy field are needed in future. Also some researches are needed to improve effectiveness of herbicirdes under upland conditions.

• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2005년도 추계 학술발표논문집
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• pp.11-14
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• 2005

• 한국응용곤충학회지
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• 제15권4호
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• pp.169-178
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• 1976

솔잎혹파리 (Thecodiplosis japonensis Uchi. et Inouye)의 충영속 유충과 충영을 탈출하여 낙하한 토중의 유충을 대상으로 체액을 분석, 측정코저 종이 크로마토그라피법, micro-Kjeldahl법, 박층 크로카토그라피 법, 왈부르그 검압계법, Bessey-Lowry법과 Reitman-Frankel법으로 측정 또는 분석하였다. 충영과 유충과 토중의 유충에 따라 유리 아미노산, 총 질소함량의 변화, 탄수화물의 변화, 지질의 종류와 변화, 호흡능, phosphatase, GOT, ?의 활성도가 측정되었다. 유리 아미노산, 총 질소함량, 지질함량, 호흡능, acid phosphatase의 황성, GPT의 활성은 충영속의 유충에서 토중의 유충으로 진행함에 따라 감소하는 경향을 나타냈다. 그러나 trehalose의 함량과 alkaline phosphatase의 활성은 증가하는 경향을 나타냈다.

• 한국토양비료학회지
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• 제6권4호
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• pp.239-244
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• 1973

대두(大豆)의 안산(燐酸) 감수성(感受性)과 관련(關聯) 엽(葉)의 광합성(光合性)-호흡평형점(呼吸平衡點)과 유리(遊離) 아미노산에 대(對)한 질소원(窒素源)의 영향(影響)을 조사(調査)하였다. 유리(遊離) 아미노산 함량(含量)은 암모니움 태(態)에서 최고(最高)였고 요소태(尿素態)에서 최저(最低)였다. glycine, serine, alanine과 특히 histidine이 암모니움태(態)에서 높았다. aspartic acid 는 초산태(硝酸態)에서 높았다. 광합성(光合性)-호흡평형점(呼吸平衡點)은 감수성(感受性) 품종(品種)에서 높고 초산태(硝酸態)에서 보다 암모니움태(態)에서 높았다. 감수성(感受性) 품종(品種)에서 과잉흡수(過剩吸收)된 암모니움을 광합성(光合性) 회로(回路)에서 중간대사물(中間代謝物)을 탈취(脫取)하여 조해(阻害)하고 오탄당(五炭糖) 회로(回路)와 광호흡회로(光呼吸回路)가 활발(活發)해지며 인산감수성품종(燐酸感受性品種)에서는 이러한 현상이 더욱 조장(助長)되는 것으로 나타났다.

• Journal of Ginseng Research
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• 제4권1호
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• pp.104-120
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• 1980

The effects of temperature on transpiration, chlorophyll content, frequency and aperture of stomata, and leaf temperature of Panax ginseng were reviewed. Temperature changes of soil and air under spade roof were also reviewed. Growth responses of responses of ginseng plant at various temperature were assessed in relation to suseptibillity of ginseng plants. Reasonable management of ginseng fields was suggested based on the response of ginseng to various temperatures. Stomata frequency may be increased under high temperature during leaf$.$growing stage. Stomata aperture increased by high temperature but the increase of both frequency and aperture appears not enough for transpiration to overcome high temperature encountered during summer in most fields. Serial high temperature disorder, i.e high leaf temperature, chlorophyll loss, inhibition of photosynthesis, increased respiration and wilting might be alleviated by high humidity and abundant water supply to leaf. High air temperature which limits light transmission rate inside the shade roof, induces high soil temperature(optimum soil temperature 16∼18$^{\circ}C$) and both(especially the latter) are the principal factors to increase alternaria blight, anthracnose, early leaf fall, root rot and high missing rate of plant resulting in poor yield. High temperature disorder was lessen by abundant soil water(optimum 17∼21%) and could be decreased by lowering the content of availability of phosphorus and nitrogen in soil consequently resulting in less activity of microorganisms. Repeated plowing of fields during preparation seems to be effective for sterilization of pathogenic microoganisms by high soil temperature only on surface of soils. Low temperature damage appeared at thowing of soils and emergence stage of ginseng but reports were limited. Most limiting factor of yield appeared as physiological disorder and high pathogen activity due to high temperature during summer(about three months).

• 대기
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• 제28권4호
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• pp.393-402
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• 2018

This study investigated future changes in the Arctic permafrost features and related biogeochemical alterations under global warming. The Community Land Model (CLM) with biogeochemistry (BGC) was run for the period 2005 to 2099 with projected future climate based on the Special Report on Emissions Scenarios (SRES) A2 scenario. Under global warming, over the Arctic land except for the permafrost region, the rise in soil temperature led to an increase in soil liquid and decrease in soil ice. Also, the Arctic ground obtained carbon dioxide from the atmosphere due to the increase in photosynthesis of vegetation. On the other hand, over the permafrost region, the microbial respiration was increased due to thawing permafrost, resulting in increased carbon dioxide emissions. Methane emissions associated with total water storage have increased over most of Arctic land, especially in the permafrost region. Methane releases were predicted to be greatly increased especially near the rivers and lakes associated with an increased chance of flooding. In conclusion, at the end of $21^{st}$ century, except for permafrost region, the Arctic ground is projected to be the sink of carbon dioxide, and only permafrost region the source of carbon dioxide. This study suggests that thawing permafrost can further to accelerate global warming significantly.

• 한국농림기상학회지
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• 제11권3호
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• pp.87-99
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• 2009

2006년 광릉 활엽수림지역에서 관측된 자료를 활용하여 수정된 토양-식생-대기 모델을 보정하고 연간 순생태 교환량의 계절변동성에 대한 모델의 모의 능력을 평가하고 탄소교환을 조절하는 주요 인자에 대하여 조사하였다. 수정된 토양-식생-대기 모델(mSPA model)을 1000 LST부터 1400 LST까지 관측된 낮 시간의 평균 순 생태 교환량(Net ecosystem exchange)을 모의하도록 보정한 후 총 일차 생산량(Gross primary productivity)을 계산하는데 사용하였고 생태 호흡량(Ecosystem respiration)은 관측지에서 개발된 경험식을 사용하여 추정하였다. 모델 결과는 여름철에 낮 시간의 평균 기공 전도도는 일사량과 매우 높은 상관성이 있음을 나타내었고 수증기 포차는 기공전도도의 변화에 큰 영향을 미치지는 않음을 보였다. 모델은 성장기간에 두 개의 극대값을 갖는 관측된 순 생태교환량의 계절 변동성을 모의하였다. 모델에서 계산된 연간 총 생산량과 생태호흡량, 그리고 순 생태 교환량은 각각 $964gC\;m^{-2}\;yr^{-1}$, $733gC\;m^{-2}\;yr^{-1}$ 그리고 $-231gCm\;^{-2}\;yr^{-1}$이었다. 관측값에 기반하여 산정된 연구결과와 비교할 때 모델 추정값이 약 $140gC\;m^{-2}\;yr^{-1}$ 더 많은 탄소 흡수를 보였다. 복잡한 지형에서 연간 생태 교환량 추정의 불확실성에 대하여 논의하였다.

• 한국토양비료학회지
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• 제14권4호
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• pp.224-229
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• 1982

울릉도자생(鬱陵島自生) 섬바디의 광합성(光合成) 및 호흡(呼吸)에 대(對)한 광도(光度) 및 온도(溫度)의 영향(影響)을 조사(調査)하였다. 1. 광합성(光合成)의 광포화점(光飽和点) 및 광보상점(光補償点)은 $20^{\circ}C$에서 각각(各各) 34~38klux와 4~6klux이고 광포화점(光飽和点)에서의 광합성속도(光合成速度)(호흡량(呼吸量)을 제(除)한)는 9~12mg $CO_2/dm^2/hr.$이었다. 2. 광합성적온(光合成適溫)은 $20^{\circ}C$이고 2온도범위($20{\sim}30^{\circ}C$, $30^{\circ}C{\sim}400^{\circ}C$)에서 광합성(光合成)의 $Q_{10}$치(値)는 0.8 및 0.9이고 호흡(呼吸)의 $Q_{10}$치(値)는 1.6 및 1.7이었다. 3. 자생지(自生地)의 환경조건(環境條件)에 적응(適應)하여 해발고도(海拔高度)가 높은 장소(場所)에서 자생(自生)한 식물본의 광보상점(光補償点)이 낮았다. 이상(以上)의 결과는 우리나라의 본과 가을이 섬바디생육(生育)에 적합(適合)함을 알 수 있고 하절기(夏節期)의 생육(生育)이 저조할 것임으로 다른 목초(牧草)와의 혼식재배(混植栽培)가 이상적(理想的)이라고 생각된다.