• 농촌계획
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• 제12권2호
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• pp.49-56
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• 2006

The application of domestic wastewater on rice paddies results in the accumulation of sodium(Na$^+$) to the soil. Excessive concentration of sodium may cause the deterioration of the physical characteristics of the soil, change in the osmosis of the soil, destruction of soil aggregates as well as ion toxicity due to sodium accumulation. Using domestic wastewater as irrigation water should be preceded by measures to prevent or control the soil salinization caused by sodium. Agricultural reuse of domestic wastewater were found not to cause serious problems with food safety due to heavy metals. However, pre-treatment using ultraviolet or ozone is recommended to reduce the number of bacteria and gem and for public health reasons. Using domestic wastewater has shown that reducing the standard application of chemical fertilizers by as much as 50% reduced the harvesting index by only 10%. This study has shown that it is feasible to reuse domestic wastewater on rice paddies. In order to facilitate the application, it is deemed necessary to establish wastewater treatment technologies in the future, to review criteria for recycling domestic wastewater for agricultural purposes such as conditions of soil and cropping system and to resolve conflicts with farmers and public health issues.

• 한국환경농학회지
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• 제17권4호
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• pp.341-345
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• 1998

Soil solutions were collected by zero-tension lysimeters at Kwangju, Kyunggi Province to estimate differences in ion concentration among species and horizons. Zero-tension lysimeters were installed in O, A, and B horizons in Larix leptolepis, Pinus koraiensis, and Quercus mongolica stands. Soil solution samples were collected from September 1996 through August 1998 and analyzed for $K^+$, $NA^+$, $NH_4^+$, $Mg^{2+}$, $Ca^{2+}$, $Al^{3+}$, $Cl^-$, $SO_4^{2-}$, $NO_3^-$, and $PO_4^{3-}$. The experimental site had high nitrogen loading from the atmosphere, and $NO_3^-$ was positively correlated with $K^+$ and $Mg^{2+}$. However, $NO_3^-$ and $NH_4^+$ showed a positive correlation only in the O horizon of Q. mongolica stand. Mg^(2+) deficit in the soil was predicted owing to the positive relationship of $Mg^{2+}$ with $NO_3^-$. Concentrations of $K^+$ and $Ca^{2+}$in soil solution were estimated higher in L. leptolepis than in other stands because of high leaching from the plant. Concentration of $Al^{3+}$ in soil solution was negatively correlated with soil solution pH. Mean soil solution pH of A and B horizons in P. koraiensis was lower than 4.7, however the $Al^{3+}$ concentration was lower than the toxic level to plants.

• 한국농공학회지
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• 제32권1호
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• pp.72-86
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• 1990

This study was carried out to get the basic information of irrigation plans for upland crops such as the optimum irrigation level and the project water requirement. Red peppers and cucumbers were cultivated in PVC pot lysimeters filled with 60cm deep clay loam soil. Four tensiometers were installed in each pot to measure the soil water pressure head. Six levels of irrigation were used. The results obtained from this study are summarized as follows: 1.The optimum irrigation level. The irrigation level of FC-PF2.7 was found to be the optimum level for both red pepper and cucumber with respect to the yield and the weight per fruit. In case of FC-PF2.7, total ET during the irrigation period were 1005.2mm for red pepper, and 429.6mm for cucumber, respectively. 2.soil moisture extraction patterns. Average soil moisture extraction patterns (SMEP)during the irrigation period were from 1st soil layer 43% : 32% : 16% : 9% for red pepper and 39% : 34% : 15% : 12% for cucumber, respectively. The extraction ratio of the upper soils showed very large values during the early stage of growth and decreased largely during the middle stage, and became larger in the last stage. 3.The project water requirement. Among the reference crop evapotranspiration(ETo) computation methods presented by FAO, the Penman method was found to be the best. The effective rainfall was computed by a modified USDA-SCS curve number equation. Availability ratios of the total rainfall during irrigation season were 59.2% for red pepper and 48.9% for cucumber, respectively. Net project water requirement of design year are 837.3mm for red pepper. and 502.Smm for cucumber, respectively.

• 한국토양비료학회지
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• 제42권Spc호
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• pp.47-50
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• 2009

본 연구는 경사지 밭 토양에서의 양분유실로 인한 지표수와 지하수 오염의 주요 요인인 인산과 질소에 대하여 평가하였다. 유실된 토양 중에서 흡착된 인산은 용해되어 천천히 조류들의 영양원으로 이용되고, 물에 용해된 질소와 인산은 부영양화의 주요 요인으로 조류들에 의하여 즉시 영양원으로 이용된다. 질소의 유실은 유실된 총량의 약 90%가 유출수와 침투수에 의하여 유실되고, 인산의 유실은 유실된 총량의 약 60% - 67%가 유실된 토양 입자에 흡착되어 유실되었다. 대체적으로 환경적으로 합리적인 토양 및 물 관리에 의한 적절한 토지이용, 시비관리 및 토양 보전농법은 토양 및 양분유실을 감소시킬 수 있고, 지표수와 지하수의 수질을 개선할 수 있다.

• 한국환경보건학회지
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• 제33권5호
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• pp.470-477
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• 2007

This research was conducted to evaluate the effect of moisture content on direct landfilling prohibition of organic sludge. Organic sludges with moisture content (Me) of 75 and 85% were filled in two lysimeters. The lysimeters were named as Exp.75 and Exp.85, respectively. LFG of 2,064 l was generated greatly for Exp.85, compared to 1,500 l for Exp.75. LFG generations in Exp.75 and Exp.85 were 64.1 l/kg and 157.1 l/kg as dry TS basis, and 113.6 l/kg and 266.2 l/kg as dry VS basis. Total $CH_4$ generation in LFG for Exp.85 was 1,238 l, while 1,050 l for Exp.75. $H_2S$ of $3{\sim}150$ ppmv was generated from Exp.85, which was 5 times higher than $2{\sim}30$ppmv from Exp.75. Leachate was not generated from Exp.75 during operation time. However, 420 ml of leachate was generated from Exp.85. From the results of gas generation, composition, odorous compounds, and leachate generation, landfilling of organic sludge with high MC was more harmful to the environment in spite of great LFG generation. However, direct landfilling of organic sludges without great difference of MC made a severe odor problem. Therefore, it was thought that current direct landfilling prohibition law for all organic sludge was appropriate.

• 한국지반환경공학회 논문집
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• 제4권3호
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• pp.41-49
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• 2003

열악한 지반물성을 갖는 쓰레기 매립지반를 건설부지로서 사용하고자 할 경우 상당한 침하가 유발될 수 있다. 이 경우 쓰레기 매립지반을 건설부지로 활용하고자 검토하는 지반공학자들에게는 열악한 압축 물성에 대한 파악 및 이에 대한 대책 방안이 마련되어야만 안전하고 경제적인 시공이 이루어질 수 있다. 따라서 본 논문에서는 대부분 매립 처분되고 있는 플라이애쉬를 도시 쓰레기와 함께 혼합매립함으로써 열악한 도시 쓰레기의 압축특성을 개량하여 침하를 억제할 수 있는지에 대하여 검토하였다. 이를 위해 플라이애쉬가 혼합된 도시 쓰레기에 대하여 대형압축실험과 모형매립조실험을 수행하여 압축특성에 대한 안정화 정도를 평가하고자 하였다. 실험결과, 플라이애쉬의 혼합비율이 증가함에 따라 압축성이 상당히 억제되었으나, 배수능력은 감소할 수 있으므로 실제 적용시에 이러한 특성들이 함께 고려될 필요성이 있다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.205-205
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• 2017

An excess soil water condition is one of the major problems for the field crops growing in paddy fields because of their poor drainage and less availability for oxygen uptake which leads to adversely affect the photosynthesis. Therefore, the current study was undertaken with aim to investigate the effects groundwater level on the photosynthetic response of soy bean (Urum), red bean (Arari), sesame (Geonbaek), perilla (Dayu) after the transplanting to the lysimeter to investigate the plant-water relation and their effect on photosynthesis. The chlorophyll content of the crops according to the humid conditions of the soy bean, sesame and the perilla was found to be 5%, 6.89 % and 13.7% higher than that of the groundwater treated at 40cm, respectively. On the other hand, the chlorophyll content of adzuki bean decreased 6.6% from the groundwater level of 40cm, and the sorghum decreased by 5.7%. As a result of investigating the Fv / Fm value of groundwater, the adzuki bean at 20cm above groundwater was lower than that of groundwater by 40cm immediately before flowering. The Fv / Fm value of soy bean and sesame at 40cm above groundwater were lowered by flowering under groundwater 20 cm and Fv / Fm value of sorghum is increased at 40 cm treatment immediately before flowering while the Fv / Fm values of the perilla had no significant difference in comparison to those at 20 cm and 40 cm of groundwater. In the case of chlorophyll fluorescence reaction, it is known that the when the absolute value is closer to 0.82, the stress is considered less. As a result of comparing the numerical values of the crops, it was found that the sorghum was the most stressed followed by adzuki bean and sesame, while the soy beans and perilla was found on the average, as they received less stress.

• 유기물자원화
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• 제25권2호
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• pp.33-40
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• 2017

우리나라는 폐기물매립지의 사용이 종료되면 즉시 차단형 최종복토층을 설치하고 30년간 사후관리를 하도록 규정하고 있다. 하지만 우수의 침투를 차단하는 최종복토층의 설치는 매립된 유기성 폐기물의 분해를 지연시키고, 침출수로 용출되는 오염물질의 양을 저감시킴에 따라 사후관리가 종료된 이후에 오염물질이 배출되어 주변을 오염시킬 우려가 있다. 본 연구에서는 실험실 규모의 모의매립조를 이용하여 약 7개월간 동일한 조건에서 인공우수를 주입한 후, 이후 8.4개월 동안 최종복토를 가정하여 매립지 내부로 유입되는 강수량을 달리한 경우에 침출수로 배출되는 오염물질의 양을 관찰하였다. 실험 결과로부터 폐기물 매립지의 사용종료 후 즉각적으로 차단형 최종복토층을 설치하는 것보다는 어느 정도 우수의 침투를 허용하는 임시복토층을 설치하는 것이 사후관리기간이 종료된 이후의 환경관리 측면에서 유리할 것으로 판단된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.153-162
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• 2000

A field study was performed to test effectiveness of a bloluminescent genetically engineered microorganism (GEM) for bioremediation process monitoring and control. The study employed Pseudomonas fluorescens HK44 that was the first strain approved for field application in the U.S. for bioremediation purposes. HK44 contains lux gene fused within a naphthalene degradative pathway, allowing this GEM to bioluminesce as it degrades naphthalene as well as substituted naphthalenes and other polycyclic aromatic hydrocarbons (PAHs) , Results showed that HK44 was maintained in both PAH-contarninated and uncontaminated soils even 660 days after inoculation. HK44 was able to produce bioluminescence in response to PAHs in soil. Although effectiveness of chemical remediation was not assessed due to heterogeneous distribution of contaminants, decreased concentration of naphthalene was shown in the soils, Taken together, HK44 was useful for in situ bioremediation process monitoring and control. This work is so far the only field release of a GEM for bioremediation purposes.

• 한국농공학회지
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• 제35권1호
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• pp.67-75
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• 1993

This study is to analyze both root growth and soil moisture extraction pattern during the growing period of upland crops with respect to soybean, redpepper, sesame. Field and lysimeter tests were conducted under 12 treatments of soil moisture level by the San Cristobal experimental design(1981) and 3 soil type(sand, sandy loam, silty loam) for 4 years('87-'90) at the experimental plot of Rural Development Administration located in Suwon. The results of this study are summarized as follows : 1.For soybean, redpepper and sesame, root growth in dry soil was better than that in wet soil and it could be expressed as a sin function in terms of time. Maximum root depth was about 55cm, 44cm, 40cm respectively. 2.The average soil moisture extraction pattern for soybean, redpepper and sesame were 61.4%, 62.8%, 79.5% for zone l(0-l5cm). 25.5%, 27.1%, 18.3%, for zone 2(15-30cm).11.4%, 9.8%, 2.3% for zone 3(30-45cm), 1.7%, 0.3%, 0.04% for zone 4(45-60cm) respectively. This means that Zone 1 would be the dominant zone in irrigation scheduling. 3.With respect to soybean, the soil moisture extraction pattern(SMEP) was varied somewhat according to the erent maintenance of soil moisture level. The average SMEP for high maintenance of soil moisture was 46%, 29%, 17%, 8%, for middle maintenance of soil moisture was 43%, 29%, 17%, 11 % and for low maintenance of soil moisture was 40%, 28%, 20%, 12%, respectively. 4.With respect to soybean, the soil moisture in the upper layer was distinctly consumed more than that in the lower layer for clay loam soil and the soil moisture of all layers was consumed evenly for sand soil. The SMEP for sandy loam soil showed a middle result compared with the above 2 soil types.