• The Korean Journal of Quaternary Research
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• v.31 no.2
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• pp.1-12
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• 2017

A total of 23 specimens were collected from the trench sections of the archaeological area, around Yongseong-ri, Buryang-myeon, Gimje. The diatoms identified to 61 species belonging to 32 genera and species diversity and abundance were very few. Three diatom assemblage zones were set up according to the vertical assemblage of each horizons, the absolute abundance of diatoms and the distribution of indicator species. In diatom assemblage zone I, marine species was mainly occurred. Because the marine species is not reported in study of the adjacent area, it is valuable data on sea-water inflow. In diatom assemblage zone II, the yield of brackish and freshwater species are abundant, indicating that the brackish water environment was caused by the influx of freshwater. In diatom assemblage zone III, the yield of freshwater species is high and species of genus Eunotia are mainly occurred. It is considered that they are deposited in wet soil environment where freshwater inflows occasionally.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.443-443
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• 2018

새만금유역의 동진강유역에 위치한 동진강제수문은 서해 바닷물 역류에 따른 농경지의 염분피해를 예방하고 고부천과 연계된 부안지역의 농업용수 공급을 위해 설치되었다. 동진제수문은 그간 정읍시 신태인읍, 김제시 부량면, 부안군 백산면의 약 770 ha 농경지에 대해 염분피해를 예방하였고 영농과 한발 시에는 부안군 일대 농경지에 농업용수를 공급할 수 있었다. 하지만 새만금 간척사업등 대규모 국토개발로 주변 자연환경이 크게 변화하여 제수문은 염해방지기능을 상실하게 되었고 현재는 농업용수 공급원으로써의 기능만 남아 있다. 현재 동진강제수문은 관개기에 농업용수 취수를 위해 수문을 닫아 본류의 유량을 저류시키고 있으며, 비관개기에도 대부분 제수문을 닫아놓는 형태로 운영되고 있다. 이러한 갑문폐쇄로 인해 하류의 유입유량이 차단되고 상류 체류시간이 증가되어 수질에 영향을 미칠 것으로 사료된다. 농업용수사용을 위해 저류되어있는 유량을 효율적으로 방류한다면, 외부수자원에 의존하지 않고 유역 내에서 자체적으로 새만금호의 유입량을 확보할 수 있을 뿐만 아니라 동진강 하류의 수질개선에도 기여할 것으로 판단된다. 본 연구에서는 동진강제수문의 내용적을 산정하여 용수공급능력을 파악하였고, 새만금유역과 호 내의 복잡한 수체 형상, 유입 및 유출 구조를 반영하는데 적합한 모델을 적용하였다. 재현성이 검토된 모델 결과를 이용하여 새만금호의 유입부인 동진강 하류의 수질을 모의하였으며, 구성한 모형의 결과와 용수공급능력을 바탕으로 동진강제수문에서의 방류조건을 가정하여 모의를 수행하였다. 방류조건별 수질개선효과를 살펴보면, Scenario 3 > Scenario 2 > Scenario 1의 순서로 수질개선율이 크게 나타났다. 동진강제수문에서의 방류량이 증가할수록 하류의 농도가 점차 감소하는 것으로 나타났으며, 이러한 결과는 동진강제수문의 방류량으로 인해 유황이 개선되고 호 내 오염부하농도가 감소하는 것으로 판단된다. 따라서 농업용수 필요량을 제외한 유량을 하류의 환경유지용수로 확보하고 이를 수질관리취약 시기에 탄력적으로 방류하여 정체수역의 수질오염을 감소시키고 목표수질을 만족하도록 운영되어야 할 것으로 판단된다.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.2
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• pp.137-145
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• 2014

Rice-barley double cropping system is typical in southwestern part of South Korea. However, the information of carbon dioxide ($CO_2$) exchange for barley growing season has still limited in comparison with rice. Using the eddy covariance (EC) technique, seasonal variation of $CO_2$ exchange was analyzed for the barley growing season at a rice-barley double cropping field in Gimje, Korea. The effects of environmental factors and biomass on the $CO_2$ flux also were investigated. Quality control and gap-filling of flux data were conducted before this analysis and investigation. The results indicated that $CO_2$ uptake increased rapidly at tillering stage and maximum net ecosystem exchange of $CO_2$ (NEE) occurred at the early of May, 2012 ($-11.2gCm^{-2}d^{-1}$), when the heading of barley occurred. NEE, gross primary production (GPP), and ecosystem respiration (Re) during the barley growing season were -348.0, 663.3, and $315.2gCm^{-2}$, respectively. In this study, an attempt has been made to measure NEE, GPP, and Re with the help of the EC system for the barley growing season for the first time in Korea, focusing on $CO_2$ exchange between the biosphere and the atmosphere.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.4
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• pp.273-281
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• 2013

Based on the results of continuous flux measurements at the Gimje paddy flux site in the southwestern coast of Korea, carbon dioxide and energy exchanges between customarily cultivated rice-barley double cropping paddy field and the atmosphere during the 2012 rice growing season (from $9^{th}$ Jun. 2012 through $20^{th}$ Oct. 2012) were analyzed. Carbon dioxide and energy (H, LE) fluxes were estimated by the eddy covariance method. Environmental parameters (net radiation, precipitation, etc.) and plant biomass (LAI, plant height, etc.) were measured along with fluxes. After the quality control and gap-filling, the observed fluxes were analyzed. The results have been showed that net ecosystem exchange (NEE), gross primary production (GPP), and ecosystem respiration (Re) during the rice cropping period were -277.1, 710.3, and 433.2 g C $m^{-2}$, respectively.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.4
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• pp.337-347
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• 2016

Carbon dioxide ($CO_2$) and methane ($CH_4$) were measured in a rice-barley double cropping and rice mono cropping paddy fields, which are located in the southwestern coast of Korea, over a one-year period. Net ecosystems $CO_2$ exchange (NEE) and ecosystem respiration (Re) were estimated by the eddy covariance (EC) method, and an automatic open/close chamber (AOCC) method was used to measure $CH_4$ fluxes. Environmental factors (solar radiation, air temperature, precipitation etc.) were also measured along with fluxes. After the quality control and gap-filling, the observed fluxes were analyzed. As a result, NEE was -603.0 and $-471.5g\;C\;m^{-2}\;yr^{-1}$ in rice-barley double cropping and rice mono cropping paddy field, respectively. $CH_4$ emissions increased during the course of flooded days and were similar in two cropping paddy field. Accoding to rough results considering only fluxes of $CO_2$ and $CH_4$, it was estimated that the carbon absorbation in rice-barley double cropping paddy field was higher than that in rice mono cropping paddy field by $128.9g\;C\;m^{-2}\;yr^{-1}$.