• 한국환경과학회지
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• 제16권7호
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• pp.805-811
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• 2007

The purpose of this study was to invesitigate relationship between rainfall water quality and precipitation characteristic during the accumulated rainfall and rainless period. As the results of the analysis, rainfall water quality was improved in the rainfall duration. Correlation coefficients between rainwater quality and accumulated rainfall were $0.88{\sim}0.99$ except $Cl^-$. and that between rainless period and initial rainfall water quality were $0.62{\sim}0.75$. During the Asian dust event, concentration of the turbidity, BOD and electric conductivity were high. Therefore, it shows that the rainfall water quality is effected by atmospheric conditions before the rainfall events.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.937-942
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• 2005

It is necessary to estimate the runoff hydrograph and peak flood discharge using law of probability for synthetic flood control policy and design of hydraulic structures. Rainfall analysis is needed in the process of peak flood discharge estimation and the time distribution of a design rainfall is a very important process in the analysis. In this study, we estimate design flood for a small urban basin and a rural basin of medium scale which have different travel times. The Huff method is widely used in Korea for the time distribution of design rainfall to estimate design flood. So, we use Huff method and a conceptual method which is suggested in this study for the comparative purpose. The 100-year frequency rainfall is used to estimate design flood for each basin and the design flood is compared with the existing design flood. As the result, the design flood is overestimated $14.6m^3/sec$ by Huff method and is underestimated $70.9m^3/sec$ by a conceptual method for the rural basin. For the small urban basin, the design flood is excessively overestimated $294.65m^3/sec$ by Huff method and is overestimated $173m^3/sec$ by a conceptual method. The reason of excessive overestimation by Huff method in the small urban basin is that the increased rate of rainfall intensity according to the decrease of duration is large and the duration exceeds the time of concentration when the increased rainfall intensity is concentrated in a quartile. Therefore, we suggested a conceptual method for the time distribution of design rainfall by considering the rainless period and duration. Especially, the conceptual method might be useful for the small urban basin with short concentration time which the design flood is overestimated by Huff method.

• The Korean Journal of Ecology
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• 제19권5호
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• pp.453-463
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• 1996

Diurnal changes of microclimatic conditions and tissue water relations were measured at two sites where Carpinus laxiflora and C. cordata were allopatrically distributed. The microclimatic conditions at a site where C. laxiflora was distributed produced severe water stress condition during summer months. Daily maximum temperature reached $30.4^\circC$ and the highest vapor pressure deficit was 1.31 KPa when 13 rainless days were continued. During this period soil water content decreased to below the field capacity even at a depth of 20 cm and xylem pressure potential also decreased to ­2.04 MPa. However, turgor potential was maintained more than 0.4 MPa. Patterns of stomatal conductance were changed with evaporative demand and soil water availability. On the other hand, microclimatic conditions at a site where C. cordata was distributed were moderate water strees condition compared with those at a site C. laxiflora was distributed. Though soil water content was maintained above field capacity C. cordata showed a remarkable decrease in turgor potential and stomatal conductance throughout the experiment. These results indicate that there is a difference in habitat characteristics between the two species and C. laxiflora is more resistant than C. cordata to water stress.

• 환경정책연구
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• 제11권4호
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• pp.107-130
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• 2012

본 논문은 한반도의 기후변화 영향이 수자원에 미치는 영향을 물부족과 가뭄을 중심으로 분석하였고 대상지역은 4대 하천이 중심이 되었다. 물론 기후변화의 영향은 강수량의 증가로 인한 홍수피해의 증가와 온도 상승 및 강수량의 감소로 인한 가뭄의 증가로 구분되어 설명해야 한다. 하지만 본 논문에서는 자료의 한계와 홍수피해를 산정하기 위한 우리나라의 침수피해모형이 존재하지 않기 때문에 기후변화의 영향이 가뭄피해에 국한되어 연구의 한계점을 가지고 있다. 또한 기후변화가 수자원에 영향을 주는 것을 확률적으로 분석할 필요성이 있으나 본 논문에서는 gamma function을 이용하여 실패확률 5% 이내에서 추산하였기 때문에 다양한 확률모형으로 연구의 분석 방법을 확장할 수 있다. 정치한 분석을 위해서 할인율은 단기, 중기, 장기로 구분하여 각각 2.76%, 1.45%, 0.62%로 가정하여 분석하였다. 전체적인 한강수계를 제외하고는 단기에 피해비용이 발생하지 않는 것으로 나타난다. 한강의 경우는 생활용수의 급격한 증가로 인하여 물 수요가 증가하는 것이 초기에 물 부족 현상으로 인하여 지속적인 피해를 발생시키는 것으로 나타났다.