• 농촌계획
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• 제6권2호
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• pp.3-11
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• 2000

The high salt concentration of reclaimed tidelands in the beginning of reclamation interferes with the growth of most crops. Although the crops are cultivated in the unripened tidal reclaimed paddy fields after desalinization to be arable, they we apt to be injured from salt by the resalinization through accumulated salts in the root zone during the growing period. In oder to make the reasonable irrigation plan in the unripened tidal reclaimed paddy fields, the preventive water requirements of resalinization as well as leaching requirements have to be included in irrigation water requirements. The critical salinity for the normal growth of crops should be determined to estimate the preventive water requirements of resalinization, and the changes of salinity in soil and water should be analyzed during the growing period, In this study, the growth tests of crops were conducted by soil textures and water management methods in the experimental field with lysimeters, using the samples of good drainage soils and poor drainage soils. And the changes of salinity in soil and water during the growing period, were analyzed to obtain the basic data for determining the critical salinity and making the estimation criteria of the preventive water requirements of resalinization. As the results obtained from analyzing the changes of salinity during the growing period in the unripened tidal reclaimed paddy fields, the exchanging interval of water for the prevention of resalinization was estimated to be within two weeks in good drainage soils and a week in poor drainage soils. And the total exchanging requirements of water for the prevention of resalinization during the growing period was estimated to be over 280mm in good drainage soils and 540mm in poor drainage soils.

• 한국관개배수논문집
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• 제21권1호
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• pp.1-16
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• 2014

The purpose of this study is to calculate agricultural water demand as considering landuse plan of the farm land on the Saemangeum tidal land reclamation project. This study based on the farm landuse plan(2012) and considered some items which did not included previous work like prevention water for resalinization for paddy and upland and muli-purpose water for upland. This study showed that the agricultural water demand estimated $145.123Mm^3/yr$, which is needed as much $14.792Mm^3/yr$ as more water than previous work. The difference comes from the change of unit water demand. Water demand is possible to be changed if guidelines are improved and detailed design work is completed through further study. Especially, the more studies for prevention water for resalinization in a tidal reclaimed farmland and water demand for a horticulture are needed.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2020년도 정기학술대회 발표논문집
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• pp.222-222
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• 2020

• 생물환경조절학회지
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• 제24권4호
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• pp.275-280
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• 2015

본 연구는 새만금 간척지에서 비닐하우스 작물 재배 가능성 검토를 위해 녹색꽃양배추를 대상으로 일일 관수량을 달리하여 관수량에 따른 토양 염농도 및 생육특성 등을 조사하여 관수량에 의한 재염화 억제효과를 알아보고자 수행하였다. 수확기의 표토의 평균 토양 EC 는 1.5 및 $3.0mm{\cdot}day^{-1}$ 처리구에서 각각 10.9 및 $11.5dS{\cdot}m^{-1}$였으며 $6.0mm{\cdot}day^{-1}$ 처리구에서 $5.1dS{\cdot}m^{-1}$로 1.5 및 $3.0mm{\cdot}day^{-1}$ 처리구보다 52~56% 낮게 나타나 점적관수량에 따른 제염효과를 확인할 수 있었다. 화뢰의 무게는 $6.0mm{\cdot}day^{-1}$ 처리구에서 주당 371.3g으로 1.5 및 $3.0mm{\cdot}day^{-1}$ 처리구의 60.9g 및 129.1g보다 높은 값을 나타냈다. 50%의 수량감소를 보이는 토양 EC는 $7.6dS{\cdot}m^{-1}$였으며 점적관수에 의한 토양 제염효과는 $6.0mm{\cdot}day^{-1}$ 처리에서 30~40cm 깊이까지 나타났다. 따라서 새만금간척지에서 녹색꽃양배추 재배시 점적관수에 의한 토양 재염화 억제를 위해서는 $6.0mm{\cdot}day^{-1}$ 수준의 관수량으로 총 422mm의 물량이 필요할 것으로 예측된다. 그러나 염류의 이동은 토양 이화학적 특성 및 계절적 요인 등 여러 가지 환경요인에 영향을 받으므로 간척지 비닐하우스에서 점적관수에 따른 염류의 이동특성에 관한 추가적인 연구가 필요할 것으로 판단된다.

• 농촌계획
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• 제8권1호
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• pp.26-40
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• 2002

In order to plan the effective irrigation project in unripened reclaimed paddy fields, the estimation of criteria of irrigation water requirements for the normal growth of crops is very important. This study was carried out to determine the leaching requirements before cultivating crops, the consumptive use of water by the growth of crops, and preventive water requirements of resalinization during the growth period in unripened reclaimed paddy fields. The irrigation water requirements in good permeable soils were estimated as 2,530mm for culvert treatment(S1CW3) and 3,080mm for non-culvert treatment(S1NW4), which were 1.8 times and 2.4 times as high as the irrigation water requirements in common rice fields, respectively. And, in case of poor permeable soils, 3,360mm for culvert treatment(S2CW4) and 3.580mm for non-culvert treatment(S2NW4) were estimated, which were 2.5 times and 2.8 times higher than the normal irrigation water requirements, respectively.

• 한국토양비료학회지
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• 제46권4호
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• pp.281-287
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• 2013

Due to its high salt content and poor physical properties in reclaimed tidal lands, it is important to ameliorate soil physical properties to improve the efficiency of desalination. The objective of this study was to evaluate the changes of soil properties at Saemangeum reclaimed tidal saline soil with various soil amendments. Field experiment was conducted at Saemangeum reclaimed tidal land in Korea and the dominant soil series was Munpo series (coarse loamy, mixed, nonacid, Mesic, Typic, Fluvaquents). Woodchips, crushed-stone, oyster shell, coal bottom ash, and rice hull were added as soil amendments and mixed into surface soil to improve soil physical properties. There was large variability in soil hardness, but oyster shell treatment was significantly lower soil hardness at surface layer. Soil hardness was not significantly different below 15 cm depth. Infiltration rate was also significantly greater at oyster shell treatment. This may be due to the leaching of Ca ions from oyster shell and improved soil properties. However, there was no statistical significant difference of the soil bulk density, moisture content, and porosity. Improved physical properties increased desalinization rate in soil and retarded the resalinization rate when evapotranspiration rate was high. Although soil salinity was significantly decreased with oyster shell amendment, soil pH was increased that should be made up as a soil amendment. Our results indicated that oyster shell application increased infiltration rate and improved soil hardness, and thus oyster shell could be used to improve soil salinity level at Saemangeum reclaimed tidal saline soil.

• 한국토양비료학회지
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• 제46권2호
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• pp.129-135
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• 2013

This study was conducted to investigate the soil characteristics of newly reclaimed tidal land and the effect of green manure crops on soil properties. Summer green manure crops such as sesbania (Sesbania grandiflora), barnyard grass (Echinochloa spp.) and sorghum${\times}$sudangrass hybrid (Sorghum bicolor L.) were cultivated at Hwaong, Ewon, Saemangeum and Yongsangang area. Soil pH of reclaimed tidal land was relatively high, but organic matter and available phosphorus contents were lower compared to the optimum range for common upland crops. Soil nutrient contents were unbalanced for upland crop growth. Yield of green manure crops had a wide spatial variation. Nitrogen content in green manure crops was the greater in Sesbania and it was estimated that major nutrient ($N-P_2O_5-K_2O$) supply amount were 150-40-370, 220-50-170 and 140-50-250 $kg\;ha^{-1}$ from sorghum${\times}$sudangrass hybrid, sesbania and barnyard grass, respectively. Based on these results, desalination is required to grow the upland crops at newly reclaimed tidal lands and management practices are necessary to reduce the salt damage by resalinization during the growing seasons. To improve the productivity and increase the nutrient utilization rate, soil physicochemical properties need to be improved to the level for upland crops by application of organic matter and fertilizer.

• 한국토양비료학회지
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• 제47권6호
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• pp.406-411
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• 2014

Serious problems in reclaimed land agriculture are high soil salinity and poor vertical drainage, so desalinization in these soils is very difficult. Also, although desalinization is accomplished in reclaimed top soils, before long, soils are resalinized according to capillary rise of salts from the subsurface soils. To resolve these problems, multi-layered soil columns with subsurface layer of macroporous medium utilizing coal bottom ash (CBA) were constructed and the effects of blocked resalinization of these soils were investigated. In this experiment soil samples were collected from Munpo series (coarse-loamy, nonacid, mixed, mesic, typic Fluvaquents). The soil texture was silt loam and the EC was $33.9dS\;m^{-1}$. As for groundwater seawater was used and groundwater level of 1 cm from the bottom was maintained. The overall rate of capillary rise was $2.38cm\;hr^{-1}$ in soil 60 cm column, $0.25cm\;hr^{-1}$ in topsoil (30 cm) + CBA (5 cm) + subsurface soil (10 cm) column and $0.08cm\;hr^{-1}$ in topsoil (30 cm) + CBA (10 cm) + subsurface soil (10 cm) column. In multi-layered soil columns with CBA 20, 30 cm layer, wetting front due to capillary rise could not be seen in top soil layer. After 70 days capillary rise experiment water soluble Na+ accumulated in top soil of soil columns with CBA 20, 30 cm was diminished by 92.8, 96.5% respectively in comparison with Na+ accumulated in top soil of soil 60 cm column because CBA layer cut off capillary rise of salts from the subsurface soil. From these results we could conclude that the macroporous layer utilizing CBA placed at subsurface layer cut off capillary rise of solutes from subsurface soil, resulting in lowered level of salinity in top soil and this method can be more effective in newly reclaimed saline soil.

• 한국토양비료학회지
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• 제45권6호
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• pp.1222-1229
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• 2012

간척지토양은 일반적으로 매우 높은 염농도를 가지고 있으며 염고농도의 염 특히, 높은 $Na^+$ 농도는 점토의 분산을 일으키고 토양의 공극을 감소시켜 토양의 공기와 수분의 유통을 악화시키고 고농도의 염은 생리적가뭄(physiological drought)의 한 가지 형태인 낮은 수분퍼텐셜을 발생시켜서 수분과 양분의 흡수를 어렵게 한다. 따라서 간척지를 효율적으로 활용하기 위해서는 간척지 토양에 대한 제염이 선행되어야 한다. 이러한 제염 효과를 증진시키기 위해서는 상기에서 살펴본 바와 같이 물리성 개선을 통하여 토양의 화학성을 개선시켜야 한다. 본 조사를 기준으로한 간척지토양 개선은 물리성 중 물질의 이동을 용이하게 하는 심층토 내 토양압밀층 개선이 우선되어야 할 것으로 판단한다. 그리고 높은 지하수위에 의한 모세관상승에 동반한 재염화를 방지하기 위한 토양관리방안이 필요하다. 따라서 최종적으로 간척지의 효과적 재염 (Resalization)방지와 제염(Desalinazation) 방안에 대한 토질역학적 측면에서 연구가 추진되어야 한다.