• Proceedings of the Korea Water Resources Association Conference
• /
• 2004.05b
• /
• pp.1032-1036
• /
• 2004

수자원계획수립시 가장 큰 문제점 중의 하나는 관심대상유역의 관측자료가 없는 경우이다. 이와 같은 미계측유역의 경우 통상 단순히 인근관측소 자료를 면적비로 전이시켜 사용하거나, 인근 계측유역에서 유출모형의 매개변수를 추정하여 매개변수를 전이시키는 방법을 사용하고 있다. 본 연구에서는 계측유역에서 추정한 장기유출모형의 매개변수를 미계측유역으로 전이시킬 때 유역별 토양수분보유능을 이용하여 보다 객관적으로 매개변수를 전이하는 방법을 제시하였다. 방법으로는 정교한 토양수분모의가 가능한 PRMS 모형을 이용하여 자료의 정도가 높은 5개 댐지점에서 매개변수를 검${\cdot}$보정한 다음, 소양강댐과 충주댐유역을 미계측유역으로 가정하여 계측유역의 토양수분보유능과 가장 유사한 유역에 매개변수를 전이하여 결과를 분석하였다.

• Journal of Environmental Impact Assessment
• /
• v.32 no.2
• /
• pp.112-122
• /
• 2023

To restore the ecological function of contaminated soil and maximize the ecological services provided by the soil, besides the toxicity orrisk caused by pollutants, the functional aspects of the soil ecosystem should be considered. In this study, a method for evaluating the health of cleaned soil was presented, and the applicability of the proposed evaluation method was examined by applying it to soil treated with washing and landfarming. Productivity, habitat, water retention capacity, nutrient cycling, carbon retention capacity, and buffering capacity were used as soil health evaluation indicators. The results showed that the soil health was not completely recovered after remediation, and even in the case of the washed soil, the health was lower than before remediation. On the other hand, there was no significant change in soil quality due to oil pollution, but soil health deteriorated. Unlike the slightly improved soil quality after landfarming treatment, soil health was not completely restored. Therefore, the results of this study indicate that it is desirable to consider both soil quality and health when evaluating the remediation effect. The soil health evaluation method proposed in this study can be usefully utilized for the sustainable use of cleaned soil and to promote ecosystem services.

• Journal of Soil and Groundwater Environment
• /
• v.11 no.1
• /
• pp.65-76
• /
• 2006

This paper outlines the methodology of grid-based water balance for estimating the spatial distribution of recharge, which is applied to Woedo catchment in the northern area of the Jeju Island. The catchment is divided into grids and a daily water balance in each grid is computed for the period of 5 years. Daily rainfall data in each grid is interpolated from the data of 10 rainfall gauging stations. The spatial distributions of parameters such as SCS curve number, soil water retention capacity and crop coefficients are derived from GIS analyses of soil and land use characteristics. The SCS curve number is obtained by calibrating simulated runoffs with respect to the observed runoffs. The results show that the average annual rainfall increases from 1,665 mm/year to 3,382 mm/year in accordance with the topographic elevation, and the average annual recharge varies from 372 mm/year to 2,576 mm/year according to the average annual rainfall increases. Spatial variability of recharge is the highest among the water balance components such as rainfall, direct runoff, evaprotranspiration and recharge because the rate of runoff and evapotranspiration in the area with relatively low rainfall is higher than the other area.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.spc
• /
• pp.45-46
• /
• 2009

This study was carried out to identify the changes of EC during desalinization due to flooding in newly reclaimed saline soil. To do this, experimental plots were made of rotary tillage+water exchanging plot, flooding plot and rainfall flooding plot. In rotary tillage+water exchanging plot, drainage, rotary tillage and flooding were conducted at the interval of 7 days. In rotary tillage+water exchanging plot and flooding plot, plots were irrigated at the height of 10 cm. After 38 days desalinization, changes of EC values at top soil (0~20 cm) were as follows. In rotary tillage+water exchanging plot, EC decreased from $21.38dS\;m^{-1}$ to $2.16dS\;m^{-1}$ and in flooding plot, EC decreased from $13.97dS\;m^{-1}$ to $2.22dS\;m^{-1}$. In rotary tillage+water exchanging plot and flooding plot, EC values decreased below the EC criterion ($4.0dS\;m^{-1}$) of saline soil. In rainfall flooding plot, EC values decreased or increased according to amounts of rainfall and rainfall time. After 38 days, EC decreased from $16.7dS\;m^{-1}$ to $12.35dS\;m^{-1}$. In flooding plot, changes of EC due to soil depth were investigated. After 38 days desalinization, changes of EC due to soil depth were as follows. At 0~10 cm depth, EC value decreased from $13.08dS\;m^{-1}$ to $0.74dS\;m^{-1}$ (94.3% of salt was desalinized). At 10~20 cm depth, EC value decreased from $14.80dS\;m^{-1}$ to $3.69dS\;m^{-1}$ (75.2% of salt was desalinized). At 20~30 cm depth, soil was desalinized slowly compared with upper soil, EC value decreased from $13.57dS\;m^{-1}$ to $6.93dS\;m^{-1}$ (48.9% of salt was desalinized).

• Journal of Korea Water Resources Association
• /
• v.39 no.4 s.165
• /
• pp.299-311
• /
• 2006

In this paper it is outlined the methodology of estimating the parameters of water balance analysis method for calculating recharge, using ground water level rises in monitoring well when values of specific yield of aquifer are not available. This methodology is applied for two monitoring wells of the case study area in northern area of the Jeiu Island. A water balance of soil layer of plant rooting zone is computed on a daily basis in the following manner. Diect runoff is estimated by using SCS method. Potential evapotranspiration calculated with Penman-Monteith equation is multiplied by crop coefficients($K_c$) and water stress coefficient to compute actual evapotranspiration(AET). Daily runoff and AET is subtracted from the rainfall plus the soil water storage of the previous day. Soil water remaining above soil water retention capacity(SWRC) is assumed to be recharge. Parameters such as the SCS curve number, SWRC and Kc are estimated from a linear relationship between water level rise and recharge for rainfall events. The upper threshold value of specific yield($n_m$) at the monitoring well location is derived from the relationship between rainfall and the resulting water level rise. The specific yield($n_c$) and the coefficient of determination ($R^2$) are calculated from a linear relationship between observed water level rise and calculated recharge for the different simulations. A set of parameter values with maximum value of $R^2$ is selected among parameter values with calculated specific yield($n_c$) less than the upper threshold value of specific yield($n_m$). Results applied for two monitoring wells show that the 81% of variance of the observed water level rises are explained by calculated recharge with the estimated parameters. It is shown that the data of groundwater level is useful in estimating the parameter of water balance analysis method for calculating recharge.