• 대한토목학회논문집
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• 제28권2B호
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• pp.187-197
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• 2008

본 연구에서는 SWAT(Soil and Water Assessment Tool) 모형을 이용하여 경안천 유역($255.44km^2$)을 대상으로 미래 토지이용변화가 수문-수질에 미치는 영향을 분석하고자 하였다. Landsat TM(1987, 1991, 1996, 2004), $ETM^+$(2001) 위성영상으로부터 시계열 토지이용도를 작성하고, CA-Markov 기법을 이용하여 2030, 2060, 2090년도의 미래 토지이용변화를 예측하였다. 모형의 입력 자료인 수문 기상자료와 지형자료(DEM, 토양도, 하천도 등), 수질자료(SS, T-N, T-P)를 구축하고 1999, 2000년 자료를 이용하여 모형의 보정을 실시하였으며, 2001, 2002년에 대하여 검증하였다. 검보정 결과, 유출량에 대해 모형 효율성 계수는 0.59, 수질항목(Sediment, T-N, T-P)에 대한 결정계수는 0.88, 0.72, 0.68로 분석되었다. 미래 토지이용변화에 따른 유출량과 비점오염 부하량의 변화를 분석한 결과, 도시화가 진행되면서 2004년을 기준(76.3)으로 유역 평균 CN값이 2030년 76.9, 2060년 77.1, 2090년 77.4로 증가하면서 유출량이 1.4%, 2.0%, 2.7% 증가하는 것으로 분석되었다. 또한, 비점오염원의 증가로 유사량과 T-N, T-P 부하량은 2004년을 기준으로 2030년 51.4%, 5.0%, 11.7% 증가하였으며, 2060년 70.5%, 8.5%, 16.7% 2090년에 74.9%, 10.9%, 19.9% 증가하는 것으로 분석되었다.

• 스마트미디어저널
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• 제12권10호
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• pp.47-54
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• 2023

지구 온난화로 인해 갑작스러운 기후변화와 농업 생산성에 대한 이해가 점점 중요해지면서, 토양 수분 예측은 농업에서 핵심 주제로 떠오르고 있다. 토양 수분은 농작물의 성장과 건강에 큰 영향을 미치며, 적절한 관리와 정확한 예측은 농업 생산성 향상과 자원 관리의 핵심 요소이다. 이러한 이유로 토양 수분 예측은 농업 및 환경 분야에서 큰 주목을 받고 있다. 본 논문에서는 머신러닝 알고리즘인 랜덤 포레스트를 통하여 시범포를 이용하여 노지 환경 데이터를 수집하고 분석하여 데이터 특성들과 토양 수분의 상관관계를 구하고 토양 수분 실제 값과 예측값을 비교하였으며 비교 결과 예측률이 약 92%의 정확성을 갖는다는 것을 확인하였다. 추후 연구를 통해 작물의 생장 데이터 변수들을 추가하여 토양 수분 예측을 진행한다면 토양 수분에 따른 작물의 생장 속도, 적절한 관수 타이밍 등의 주요 정보를 정확하게 제어함으로써 작물의 품질 상승, 물 관리 효율 증가 등 생산성 및 자원 효율성에 좋은 영향을 미칠 것이라고 기대된다.

• 한국토양비료학회지
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• 제45권1호
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• pp.16-19
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• 2012

Increasing rice grain yield is critical for feeding rapid increasing of Asian population. However, global warming effect may be negative for sustainable rice production. Therefore it is essential to develop technologies not only for increasing grain yield but also for reducing global warming effect. Biochar, which is carbonized biomass, has a great potential of carbon sequestration and soil quality improvement, which can contribute grain yield increasing. In this study, rice yield responses to biochar application on the rice cropping system were evaluated with field experiments under different water management practices at the research farm of the University of Missouri-Columbia Delta Research Center, Portageville, MO. Biochar (i.e., $4Mg\;ha^{-1}$) was produced using field scale pyrolyzer and incorporated into the field 4 months prior to planting. Rice was grown under three different water management practices. Result showed that no significant yield difference was found in the biochar application plots compared to rice hull and control plots from the 2 years field study at the very fertile soil. However, rainfed management results in severe reduction of yield. Research concludes that the biochar application does not significantly influence on rice yield increasing especially for very fertile soils.

• Journal of Ecology and Environment
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• 제43권2호
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• pp.271-281
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• 2019

Background: The plant communities within reservoir drawdown zones are ecologically important as they provide a range of ecosystem services such as stabilizing the shoreline, improving water quality, enhancing biodiversity, and mitigating climate change. The aim of the study was therefore to identify the major environmental factors affecting these plant communities within the drawdown zone of the Soyangho Reservoir in South Korea, which experiences a monsoonal climate, and thereafter to (1) elucidate the plant species responses and (2) compare the soil seedbank composition along main environmental gradients. Results: Two main environmental gradients affecting the plant community structure were identified within the drawdown zone; these were a vertical and longitudinal gradient. On the vertical dimension, a hydrological gradient of flood/exposure, the annual-dominated plant community near the water edge changed to a perennial-dominated community at the highest elevation. On the longitudinal dimension from the dam to the upstream, plant species composition changed from an upland forest-edge community to a lowland riverine community, and this was correlated with slope degree, soil particle size, and soil moisture content. Simultaneously, the composition of the soil seedbank was separated along the vertical gradient of the drawdown zone, with mainly annuals near the water edge and some perennials at higher elevations. The species composition similarity between the seedbank and extant vegetation was greater in the annual communities at low elevation than in the perennial communities at higher elevation. Conclusions: The structures of plant community and soil seedbank in the drawdown zone of a monsoonal riverine reservoir were changed first along the vertical and secondly along the longitudinal gradients. The soil seedbank could play an important role on the vegetation regeneration after the disturbances of flood/exposure in the drawdown zone. These results indicate that it is important to understand the vertical and longitudinal environmental gradients affecting shoreline plant community structure and the role of soil seedbanks on the rapid vegetation regeneration for conserving and restoring the drawdown zone of a monsoonal reservoir.

• 한국기후변화학회지
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• 제5권4호
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• pp.277-284
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• 2014

Biochar application to soil is widely known to have effects of climate change mitigation and soil quality improvement. However, effects of biochar on soil ecosystem are not always positive and some biochars are reported to contain toxic materials which might influence soil ecosystem. In this context, this study aims to investigate behavioral changes of earthworms(Eisenia fetida, Eisenia andrei) in response to different application rates of biochar to artificial soil. Treatment included two types of biochars made from rice husk (RH_Char) and wastewater sludge (SL_Char) with 1% and 10% application rates, respectively. Avoidance test revealed that earthworms did not avoid SL_Char treatments at 1% and 10%, while they rather moved to the RH_Char treatments probably due to higher labile carbon content(Hot water extractable carbon) of the RH_Char. The HWC content of RH_Char was 4 times higher than that of the SL_Char. Results of reproduction test showed that the survival rates, number of juveniles and number of cocoons were not influenced by biochar application except for the treatment of SL_Char at 10% rate. In the SL_Char 10% treatment, fatality was approximately 3.3 times as high as the control and the number of cocoons was 1.3 times higher in the same treatment than the control, indicating that earthworms were under environmental stress. The possible explanation for the stress condition was related to higher Cd, Ni, Cr, and As contents in the SL_Char. Overall results imply that biochar application at low rate might not change earthworms' behavior for the short term, while the reproduction behavior might be negatively influenced under the high application rate.

• 한국지하수토양환경학회지:지하수토양환경
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• 제28권spc호
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• pp.18-39
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• 2023

Rapid development of geophysical exploration and hydrogeologic monitoring techniques has yielded remarkable increase of datasets related to groundwater systems. Increased number of datasets contribute to understanding of general aquifer characteristics such as groundwater yield and flow, but understanding of complex heterogenous aquifers system is still a challenging task. Recently, applications of data science technique have become popular in the fields of geophysical explorations and monitoring, and such attempts are also extended in the groundwater field. This work reviewed current status and advancement in utilization of data science in groundwater field. The application of data science techniques facilitates effective and realistic analyses of aquifer system, and allows accurate prediction of aquifer system change in response to extreme climate events. Due to such benefits, data science techniques have become an effective tool to establish more sustainable groundwater management systems. It is expected that the techniques will further strengthen the theoretical framework in groundwater management to cope with upcoming challenges and limitations.

• Weed & Turfgrass Science
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• 제2권3호
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• pp.298-305
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• 2013

아메리카 동애등에를 이용하여 음식물 쓰레기를 친환경적으로 처리하는 과정에서 생성된 동애등에 분변토(Soldier fly cast)는 음식물 발효물과 동애등에번데기가 혼합된 부산물비료이다. 본 연구는 동애등에 분변토가 혼합된 모래상토에서 자란 한국잔디의 생육과 토양의 변화를 조사하여 동애등에 분변토가 토양개량제로서 적합성을 평가하였다. 적합성 평가를 위해 USGA규격에 적합한 모래와 7% 코코피트(Coco), 7% 부산물비료(Comp), 3.5% 동애등에 분변토(1/2 SFC) 및 7% 동애등에 분변토(SFC)를 혼합하여 연구에 사용하였다. 토양분석결과, SFC 처리구에서 NA보다 CEC가 증가하였고, Coco보다 질소, 유효인산 및 칼륨이 증가하였다. 엽색지수와 엽록소지수와 같은 잔디품질은 SFC처리구에서 향상되었고, 잔디뿌리길이도 증가하였다. 잔디생육량은 SFC처리구에서 지상부, 포복경, 지하부의 생육이 모두 증가하여 잔디생육이 가장 왕성하였다. 잔디 중 함유된 양분은 SFC처리구의 지상부에서 칼륨과 칼슘 함량이 증가하였다. 이러한 결과를 종합할 때, 7% 동애등애분변토가 혼합된 모래상토는 토양의 보비력과 주요양분의 유효도가 증가하여 잔디의 지상부와 지하부의 생육과 품질이 향상시키므로 골프장 상토의 토양개량제로 활용이 가능하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.204-204
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• 2016

Thailand had set the National Water Management Strategy which covered main six areas in the next 12 years, i.e., by priority: (1) water for household, (2) water for agricultural and industrial production, (3) water for flood and drought management, (4) water for quality issue, (5) water from forest conservation and soil erosion protection, (6) water resources management. However due to the climate change impact, there is a question for all strategies is whether to complete this mission under future climate change. If the impact affects our target, we have to clarify how to mitigate or to adapt with it. Vulnerability assessment was conducted under the framework of ADB's (with the parameters of exposure, sensitivity and adaptive capacity) and the assessments were classified into groups due to their different characteristic and the framework of the National Water Management Strategy, i.e., water supply (rural and urban), water for development (agriculture and others), water disasters (floods (flash, overflow), drought, water quality). The assessments identified the parameters concerned and weight factors used for each groups via expert group discussions and by using GIS mapping technology, the vulnerability maps were produced. The maps were verified with present water situation data (floods, drought, water quality). From the analysis result of this water resources management strategy, we found that 30% of all projects face the big impacts, 40% with low impact, and 30% for no impact. It is clear that water-related agencies have to carefully take care approximately 70% of future projects to meet water resources management strategy. It is recommended that additional issues should be addressed to mitigate the impact from climate risk on water resource management of the country, i.e., water resources management under new risk based on development scenarios, relationship with area-based problems, priority definition by viewpoints of risk, vulnerability (impact and occurrence probability in past and future), water management system in emergency case and water reserve system, use of information, knowledge and technology in management, network cooperation and exchange of experiences, knowledge, technique for sustainable development with mitigation and adaptation, education and communication systems in risk, new impact, and emergency-reserve system. These issues will be described and discussed.

• 한국토양비료학회지
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• 제26권4호
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• pp.253-258
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• 1993

배추에 유황(硫黃)을 시용(施用)한 후(後) 수량(收量), 수확기(收穫期) 토양(土壤)과 엽중(葉中) 유기(有機), 무기성분(無機成分)의 변화(變化)와 품질(品質) 개선(改善) 효과(效果)를 연구(硏究)한 결과(結果)는 다음과 같다. 1. 유황(硫黃)을 배추에 10~30kg/10a 시용(施用)하였을 때 약 10% 증수(增收)되었다. 2. 토양(土壤) 분석(分析) 결과(結果) 유황(硫黃) 시용(施用)으로 유효(有效) 유황(硫黃). 함량(含量)이 증가(增加)하고 그 반면 pH가 낮아졌다. 3. 유황(硫黃) 시용(施用)에 따라 배추 엽중(葉中) nitrate의 함량(含量)이 감소(減少)되었다. 4.유황시용(硫黃施用)으로 배추의 맛과 향미(香味)에 관련(關聯)되는 water-solubl pectin, phenolic compound, sugar, vitamin C의 함량(含量)이 증가(增加)되었으며 식미(食味) 검사(檢査)에서는 유황시용(硫黃施用)으로 배추의 독특(獨特)한 향기(香氣), 맛과 조직감(組織感)에서 훨씬 향상(向上)되었다.

• Environmental Engineering Research
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• 제16권2호
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• pp.61-67
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• 2011

The water quality from nonpoint source run off results from different land use types has been studied. The construction of a buffer strip is one method of nonpoint source pollutant control. The Soil and Water Assessment Tool (SWAT) model has been applied to estimate the pollutant removal through the buffer strip. When the non-business land has been changed into grass to form a buffer-strip, the change of land use effects the results of the model according to measures of the water quality. The data from a water level station within the watershed in the years 2006 and 2007 was used for calibration and validation of the model. Under the rainfall conditions in 2007, the removal rates of SS, BOD, TN, TP were 11.5%, 9.5%, 1.2%, and 4.5%, respectively. During the rainy days, the removal rates at the buffer strip were 92.3% of SS, 91.2% of BOD, 82.4% of TN, and 83.5% of TP. The pollutants from nonpoint sources were effectively removed by over 80% as they passed through the buffer strips. Rainfall resulted in soil erosion, which led to an increase in the SS concentration, therefore, the construction of buffer strips protected the streams from SS inflows. Since TN concentrations are affected by the inflows of ground water and the N concentration of the rainfall, the removal rate of TN was relatively lower than for the other pollutants.