• 한국유기농업학회지
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• 제24권2호
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• pp.221-234
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• 2016

본 연구는 벼에 돈분액비와 화학비료를 연용하여 살포하였을 때 돈분액비가 벼의 수량과 미질 및 토양 화학성에 미치는 영향을 구명하고자 2012년부터 3년간 수행하였다. 시험은 강원도 철원군 농가 포장에서 오대벼를 공시하여 실시하였다. 시비는 돈분액비를 질소 검정시비량을 기준으로 하여 100%에 해당하는 양을 처리하였으며, 화학비료 처리구와 비교하였다. 돈분액비의 시용년수에 따른 벼의 분얼수 및 초장은 돈분액비 1년 시용구와 화학비료 사이에 유의한 차이를 나타내지 않았다. 돈분액비 3년 시용구의 분얼수는 화학비료 시용구보다 많았다. 쌀의 수량은 돈분액비 1년 시용구가 화학비료 대비 7% 감소하였다. 그러나 돈분액비 3년 연속 시용구에서 $495kg\;10a^{-1}$의 수량을 얻어 화학비료 대비 8% 증수하였다. 돈분액비로 벼를 3년 재배하였을 때 쌀의 단백질 함량은 7.01%로 대조구인 화학비료 시용구 보다 높은 수준이었다. 아밀로스 함량은 15.5~17.0%로 처리구별 유의성은 없었다. 식미치를 Toyo 식미계를 이용하여 조사한 결과 돈분액비 100% 처리구의 식미치가 65.3%로 화학비료 시용구보다 낮은 수준이었다. 쌀의 품위 특성에서 돈분액비 100% 처리구의 완전미 비율은 78.7%로 낮았으며, 불완전미의 비율을 높인 주 원인은 분상질립, 피해립의 비율이 높았기 때문이었다. 3년간 돈분 액비를 계속 사용한 결과, 화학비료 처리에 비해 토양 중 칼륨과 아연의 함량이 높았으나 다른 중금속 함량도 관행 화학비료 처리와 크게 다르지 않았다. 이상의 결과를 미루어 볼 때 돈분액비의 3년 시용시 돈분 액비의 연용이 쌀의 수량성에 나쁜 영향을 미치지는 않을 것으로 판단되지만 쌀의 단백질 함량이 증가하고 Toyo 식미치와 완전미 비율은 감소하는 결과를 얻었다. 돈분액비 3년 시용 후 토양의 칼륨 축적이 되므로 토양검정에 의한 액비 적량시용이 요구된다.

• 환경정책연구
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• 제5권2호
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• pp.27-47
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• 2006

토양오염실태조사 및 특정토양오염관리대상시설 부지 등에서 토양오염조사의 효율을 획기적으로 높일 수 있는 정책제안의 마련을 시도하였다. 우리나라 정부기관에서 토양이 오염된 부지를 찾아 내는 조사효율이 2% 정도로 매우 낮은바, 이에 대한 근본적인 요인 분석과 더불어, 토양오염조사에 관한 미국, 영국, 독일, 네덜란드, 일본의 법 제도 비교 분석을 통해 다음의 네 가지 정책방향을 제안하였다. 첫째, 토양오염 의혹부지에 대한 이해당사자로 하여금 적극적으로 당해 부지의 토양오염 여부를 조사할 수 있도록 책임법규로서의 토양환경보전법의 기능을 보완하고 강화해야 한다. 둘째, 토양오염실태 조사 및 토양오염관리대상시설과 관련된 토양오염조사가 적극적으로 이루어질 수 있도록 토양오염조사체계를 획기적으로 개선해야 한다. 토양오염 의혹부지에 관련된 이해당사자가 민원을 제기하고, 토양오염조사 결과에 대해 인센티브를 얻고 책임을 질 수 있는 민간 환경전문업체가 토양오염조사를 수행할 수 있는 새로운 토양오염조사체계를 고려해야 한다. 셋째, 토양오염신고 제도의 강화이다. 현행 토양오염신고 제도의 의무화를 고려할 수 있다. 나아가서는 일정 규모의 토양오염 이상에 대해서는 이로부터 영향을 받을 수 있는 주민 등이 이를 인식할 수 있도록 공시하는 것도 고려해 볼 수 있다. 넷째, 토양이 오염된 부지를 찾음으로써 인센티브를 얻을 수 있는 민간 환경전문업체가 토양환경 평가의 수행기관으로 포함되는 것이다.

• 한국토양비료학회지
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• 제48권6호
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• pp.641-647
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• 2015

Monitoring of soil fertility by long-term application of fertilizers is necessary to improve the fertility of soil and the productivity of crop. The objective of this study was conducted to investigate the changes of exchangeable Mg by continuous application of fertilizers from 1969 to 2014. The treatments were no fertilization (No fert.) and fertilization (NPK, NPK+C, NPK+S, and NPK+CS). The concentration of exchangeable Mg in No fert., NPK+C, and NPK+S treatments tended to increase from 1965 to 1975, but decrease gradually from 1976 to 1987, and increase again after 1988. Based on these, the changes of exchangeable Mg were divided into period I ('69 ~'75), period II ('76~'87), and period III ('88~'14). Especially, exchangeable Mg decreased in the period II. This was presumed that a significant amount of Mg from topsoil were leached into subsoil by break of plow pan and some of subsoil was incorporated into topsoil according to change of plowing depth by replacement of tillage machinery. It could be possible that exchangeable Mg in NPK, NPK+S, and NPK+CS was accumulated in the depth of 15~20 cm. For the period III, exchangeable Mg in No fert., NPK, NPK+C, NPK+S, and NPK+CS treatments increased at rates of 0.013, 0.018, 0.015, 0.023, and $0.024cmolckg^{-1}{\cdot}yr^{-1}$ respectively. Exchangeable Mg level in NPK+S was lower than the other treatments in the period I and period II, but higher than in the period III. This result was attributed to replacement of silicate fertilizer type from wollastonite (Mg 0.3%) to silicate fertilizer (Mg 3%). Also, exchangeable Mg level of No fert. treatment increased, which showed that Mg concentration of irrigated water had the greatest impact on Mg accumulation of soil. Recently, Mg level of irrigated water tended to increase, indicating that Mg concentration of water will affect greatly the concentration of exchangeable Mg of soil in the future. Like these, the changes of exchangeable Mg were greatly influenced by agricultural environment such as plowing depth, plow pan, content of fertilizer, and quality of irrigated water. Considering these agricultural environment, the proper management of soil is needed for the improvement of soil fertility and crop productivity.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.708-714
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• 1999

For the assessment of the level of stream pollution, SWAT-WASP model linked with GIS was applied to a respresentative rural watershed and evaluated for its applicability through calibration and verfication using observed data. Using daily water yields, sediment yields and nutrient discharge simulated by SWAT model, WASP input file was build. Point source pollutant and water quality change in stream was considered in WASP model. For the model applicatiion , digital maps were constructed for watershed boundary, ladn-use , soil series , digital elevation, and topographic data of Bok-Ha watershed using GRASS. The model application results showed that the simulated runoff was in a good agreement with the observed data and indicated reasonable applicability of the model.

• 한국GIS학회:학술대회논문집
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• 한국GIS학회 1995년도 추계학술대회 발표요약문
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• pp.22-32
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• 1995

본 연구의 목적은 경안천 유역의 토지이용 및 식생의 활력도를 살피고, 각 시점에서의 토양유실량을 추계하며, 토지이용변화에 따른 토양유실 변화량의 증감을 분석하는데 있다. 토양유실량은 토양유실량예측공식(USLE)을 이용하여 산정하였는데 경안천이라는 광역적인 유역의 토양유실을 분석하기 위하여 GIS기법과 원격탐사기법을 동시에 이용하였다. 경안천 유역의 토지이용 및 식생활력도변화 분석뿐만이 아니라 토양유실량의 정확한 산정은 유역환경의 질에 영향을 미치는 매우 중요한 인자들이 무엇인지를 분석케 하였다. 즉 식생, 경사도 및 사면장 그리고 토양보전과 관련된 인자들에 대한 관리는 하천유역의 보전 및 토양유실의 저감에 중요한 역할을 함을 알 수 있었다. GIS기법을 응용한 본 연구는 계획가들에게 있어서 하천유역의 토지이용의 변화와 토양유실량의 상관성을 파악하게 해줌으로서 앞으로의 유역내의 장기적인 토지이용계획 수립시 매우 합리적인 지침을 제시해 줄 것으로 기대된다.

• 한국농공학회논문집
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• 제48권3호
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• pp.35-45
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• 2006

Fallow paddy areas have been increased due to the import of cheap agricultural product, and the unbalance between farming cost and rice price since 1990. In domestic, rice production control that decrease paddy field area has been introduced for the control of rice demand and supply and stabilization of rice price since 2003. Because of the desire of paddy field's owner to create benefit by using paddy for other object, fallow paddy would be continuously increased. In the other aspect, many people in the world is suffering from hunger because of the shortage of food. In case of Korea, continuous drought and flood damages will be potential concern of stable food supply. From this viewpoint, the increasing fallow paddy area needs to be protected from the devastation by weed breeding for the re-cultivation. In this study, fallow paddy managed with the shallow pools and shallows was selected fur monitoring and analyzing of water quality and plant body change. As the results, the managed fallow paddy found to be effective in the purification of water quality and the control of plant growth.

• 농업과학연구
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• 제46권1호
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• pp.205-217
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• 2019

The aim of this study was to identify land resources because food production and supply in North Korea have been at risk due to variations in its seasonal climate. More than three-fifths of the soils are locally derived from the weathering of granitic rocks or various kinds of schists developed from crystalline rocks. Well-developed reddish brown soils derived from limestone are found in the North Hwanghae province and in the southern part of the South Pyeongan province. Additionally, a narrow strip of similarly fertile land runs through the eastern seaboard of the Hamgyong and Kangwon Provinces. The loss of clay particles and organic matter are major causes of degradation in the soil physical and chemical properties in North Korea. 75% of the areas converted from forests became croplands, and 69% of the land converted to croplands came from forests. The net forest loss was quite small from the 1990s to the 2000s. However, deforestation in areas with a slightly lower elevation and gentler slope between 1997 and 2014 led to severe soil erosion resulting in a drastic change in the physical and chemical properties of the soil which influenced cropland stability and productivity. Therefore, the drastic changes in land cover as well as in the physical and chemical properties of the soil caused by various geographical features have seriously influenced the productivity of crops in North Korea.

• 한국대기환경학회지
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• 제29권6호
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• pp.789-800
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• 2013

$N_2O$ and $CH_4$, Greenhouse gas emission, Forest soil, Closed chamber technique, Soil uptake $N_2O$ and $CH_4$ are important greenhouse gases (GHG) along with $CO_2$ influencing greatly on climate change. Their soil emission rates are highly affected by bio-geo-chemical processes in C and N through the land-atmosphere interface. The forest ecosystems are generally considered to be net emission for $N_2O$; however, net sinks for $CH_4$ by soil uptake. Soil $N_2O$ and $CH_4$ emissions were measured at Mt. Taewha in Gwangju, Kyeonggi, Korea. Closed chamber technique was used for surface gas emissions from forest soil during period from May to October 2012. Gas emission measurement was conducted mostly on daytime (from 09:00 to 18:00 LST) during field experiment period (total 25 days). The gas samples collected from chamber for $N_2O$ and $CH_4$ were analyzed by gas chromatography. Soil parameters were also measured at the sampling plot. GHG averages emissions during the experimental period were $3.11{\pm}16.26{\mu}g m^{-2}hr^{-1}$ for $N_2O$, $-1.36{\pm}11.3{\mu}gm^{-2}hr^{-1}$ for $CH_4$, respectively. The results indicated that forest soil acted as a source of $N_2O$, while it acted like a sink of $CH_4$ on average. On monthly base, means of $N_2O$ and $CH_4$ flux during May (spring) were $8.38{\pm}48.7{\mu}gm^{-2}hr^{-1}$, and $-3.21{\pm}31.39{\mu}gm^{-2}hr^{-1}$, respectively. During August (summer) both GHG emissions were found to be positive (averages of $2.45{\pm}20.11{\mu}gm^{-2}hr^{-1}$ for $N_2O$ and $1.36{\pm}9.09{\mu}gm^{-2}hr^{-1}$ for $CH_4$); which they were generally released from soil. During September (fall) $N_2O$ and $CH_4$ soil uptakes were observed and their means were $-1.35{\pm}12.78{\mu}gm^{-2}hr^{-1}$ and $-2.56{\pm}11.73{\mu}gm^{-2}hr^{-1}$, respectively. $N_2O$ emission was relatively higher in spring rather than other seasons. This could be due to dry soil condition during spring experimental period. It seems that soil moisture and temperature mostly influence gas production and consumption, and then emission rate in subsoil environment. Other soil parameters like soil pH and chemical composition were also discussed with respect to GHG emissions.

• 한국수자원학회논문집
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• 제50권6호
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• pp.373-386
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• 2017

본 연구에서는 새만금유역과 호 내의 복잡한 수체 형상, 유입 및 유출 구조를 반영하는데 적합한 모델을 적용하고 재현성이 검토된 모델 결과를 이용하여 호 내 수질을 모의하였다. 또한 구성한 모형의 결과를 바탕으로 만경강, 동진강의 상류에 위치하고 있는 제수문에서의 방류조건을 가정하여 모의를 수행하였다. 방류조건별 모의 결과, 만경강을 통해 유하하는 호 상류부인 M3, 동진강을 통해 유하하는 호 하류부인 D5지점에서 목표수질을 초과하는 것으로 나타났고 새만금호 상류부인 M3, D3지점은 방류조건에 따른 수질개선효과가 큰 것으로 예측되어 만경강과 동진강의 유입수의 영향이 지배적인 것으로 평가되었다. 전량방류시 영향범위를 거리로 살펴보면 만경강대교에서 새만금호 하류방향으로 약 22 km지점, 동진강대교에서 새만금호 하류방향으로 약 15 km지점까지로 나타났다. 농도변화와 방류조건별 영향범위를 살펴보면, 하류측으로 갈수록 수질개선에 영향을 적게 미치지만, 증가된 방류량에 의해 수질이 개선되어 제수문에서의 방류량 증가는 호 내 수질개선에 기여하는 것으로 판단된다.

• 한국환경농학회지
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• 제39권1호
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• pp.50-57
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• 2020

BACKGROUND: Biochar is used in various environmental fields, such as water quality and soil restoration, and affects soil fertility and nutrient cycling. Also, when crops are grown on biochar-applied soil, their characteristics may be affected. Biochar is used especially with commercial vegetable seedlings. METHODS AND RESULTS: The objective of this study was to determine the effects of biochar content in seeding mixes on early growth of lettuce (Lactuca sativa L.), Chinese cabbage (Brassica rapa L.), and red pepper (Capsicum annuum L.). Treatments consisted of a control (0: 10, ratio of biochar to seeding mixes (w/w)), 1: 9 (biochar 10%), 3: 7 (biochar 30%), 5: 5 (biochar 50%), and 7: 3 (biochar 70%). The biochar was made from risk husk and had a C/N ratio of 104. As the mixing ratio of biochar increased, pH increased whereas EC and nitrogen content decreased. The highest phosphorus content was with the treatment of 30% biochar, while there were significant increases in the weight of lettuce seedlings and concentrations of T-N, P₂O₅, K₂O, MgO, and Na with the treatments of 30% and 50% biochar. Although the weight of Chinese cabbage seedlings increased with the treatment of 10% biochar, the increase was not statistically significant. Also, there was an increase in the weight of red pepper seedlings with the treatment of 30% biochar, but the increase was not statistically significant. With increases in the biochar mixing ratio, the K₂O concentration of red pepper seedlings increased, but the concentrations of P₂O₅, CaO, MgO, and Na decreased. It was believed that this was because of absorption inhibition by calcium-phosphate formation in the seeding mixes owing to increased pH. CONCLUSION: In conclusion, adding biochar to seeding mixes is considered to be an important mean for growing healthy vegetable seedlings. More field experiments are needed to verify the effect of biochar on vegetable crop growth over the entire growing season.