• 한국농공학회논문집
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• 제60권3호
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• pp.113-121
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• 2018

The objectives of the research were 1) to develop the low-cost and high efficient desalination system to treat brackish water having high salt contents for irrigation at greenhouses near coast, and 2) to monitor and assess the effects of the brackish water desalination system on soil environment and growth in squash greenhouse cultivation area. The monitoring site was one of the squash greenhouse cultivation farm at Choengam-ri, Jinsang-myun, Gwangyang-si, Jeonnam-Do Monitoring results for groundwater irrigation water quality, and salinity showed a remarkable difference between control and treatment group. The salinity of soil at treatment group was less than at control group. While, the system made possible to increase the squash quantity from 4.7 ea to 6.3 ea at each and the average weight of the harvested squash was increased from 277.2 g to 295.1 g. The applied brackish water desalination system may be appled to reclaim sea or brackish irrigated area as alternative water resources, although long-term monitoring is needed to get more representative results at different level of salinity.

• Journal of Plant Biology
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• 제12권3호
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• pp.35-41
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• 1969

To clarify the types of brackish region of the Han River Estuary, this research was carried out, and the results obtained on the basis of salinities and phytoplankton are as follows: 1. Geomorphologically, the Han River Estuary is the drowned river valley type. 2. According to the Venice System, the estuarine extent is defined from the lower point of Jollyu-ri to Palmi Island. As a whole the estuarine region is mixo-haline including parts from oligo-haline to poly-haline. 3. In standpont of phytoplankton frequency, the frequency of fresh-water species is high in the upper region of estuary and that of marine species is high in the lower region. The rate of frequency of fresh-water species is inversely proportionate to that of marine species. The area mixedby marine and fresh-water species over estuarine boundary. 4. The frequency of some typical brackish species is very low and almost similar in the whole region.

• 한국어류학회지
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• 제18권3호
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• pp.184-192
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• 2006

제주연안에 서식하는 검정망둑 Tridentiger obscurus의 생식주기를 조사하기위해 기수지역에서 2004년 5월부터 2005년 8월까지 총 408마리, 조수웅덩이에서 2004년 7월부터 2005년 8월까지 총 271마리를 채집하였다. 기수지역의 수온은 $11.0{\sim}21.6^{\circ}C$이었다. 조수웅덩이의 수온은 2004년 7~8월에 $30.1{\sim}29.2^{\circ}C$의 범위였으나, 2005년의 수온변화는 기수지역과 유사하여 $11.1{\sim}24.5^{\circ}C$로 조사되었다. 기수지역 암컷의 GSI는 4월에 증가하기 시작하여 5~8월에 높은 값을 유지하였다. 기수지역 검정망둑의 생식주기는 미성숙기 (11~5월), 성숙기 (3~9월), 완숙 및 산란기 (5~9월), 퇴행기 (7~12월)로 조사되었다. 조수웅덩이 암컷의 GSI도 4월에 빠르게 증가하기 시작하여 2005년 7월까지 높은 값을 유지하였다. 그러나 고수온 시기인 2004년 7월에는 낮은 값을 나타내었다. 조수웅덩이에 서식하는 검정망둑의 생식주기는 미성숙기 (8~4월), 성숙기 (3~8월), 완숙 및 산란기 (3~7월), 퇴행기(2004년 7~8월, 2005년 8월)로 조사되었다. 기수지역과 조수웅덩이에 서식하는 검정망둑의 포란수는 각각 1,214~12,109와 2,427~13,892의 범위였고 포란수는 조수웅덩이가 기수지역보다 높았다 (P<0.05). 그리고 두 지역 모두 전장과 체중이 증가할수록 포란수가 증가하는 경향이 있었다. 기수지역에서 전장 111 mm 이상인 개체들은 산란시기에만 관찰된 반면 조수웅덩이에서는 2004년 10월 이후부터 지속적으로 관찰되었다. 그리고 기수지역과 조수웅덩이에서 이러한 개체들의 출현빈도는 각각 0~12%와 11.4~57.9%이었다. 이들 결과로 보아, 검정망둑의 난소 발달은 수온 및 일장의 변화와 밀접한 관련이 있다고 생각된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권6호
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• pp.95-105
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• 2021

Extensive groundwater abstraction has been recognized as one of the major challenges in management of coastal groundwater. The purpose of this study was to assess potential changes of groundwater distribution of northeastern Jeju Island over 10-year duration, where brackish water have been actively developed. To quantitatively estimate the coastal groundwater resources, numerical simulations using three-dimensional finite-difference density-dependent flow models were performed to describe spatial distribution of the groundwater in the aquifer under various pumping and recharge scenarios. The simulation results showed different spatial distribution of freshwater, brackish, and saline groundwater at varying seawater concentration from 10 to 90%. Volumetric analysis was also performed using three-dimensional concentration distribution of groundwater to calculate the volume of fresh, brackish, and saline groundwater below sea level. Based on the volumetric analysis, a quantitative analysis of future seawater intrusion vulnerability was performed using the volume-based vulnerability index adopted from the existing analytical approaches. The result showed that decrease in recharge can exacerbate vulnerability of coastal groundwater resources by inducing broader saline area as well as increasing brackish water volume of unconfined aquifers.

• 한국해양학회지:바다
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• 제19권4호
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• pp.243-255
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• 2014

본 연구는 섬진강 하구역에서 저서다모류군집의 시 공간적 분포 및 환경 요인과의 상관관계를 파악하기 위해 2012년 4월부터 2013년 2월까지 24개의 정점을 대상으로 소조시 만조 때 조사를 실시하였다. 수질환경요인으로 염도, 수온, 용존산소, pH 등을 측정한 결과를 바탕으로 조사지역은 세 해역으로 구분하였다. 각 정점별 환경 특성 차이에 따라 Saline Water Zone(SWZ), Brackish Water Zone(BWZ), Fresh Water Zone(FWZ)으로 정의하였다. SWZ은 대개 30 psu를 상회하였으며, BWZ에서는 염도가 급격히 감소하였고, FWZ에서는 거의 0 psu를 보였다. SWZ에서는 수온의 계절 변동이 가장 적었으며, DO는 가장 낮은 값을, pH는 시공간적 변동이 거의 없이 일정한 값을 유지하였다. 반면 FWZ에서는 수온의 계절 변동이 심하였으며, DO는 가장 높은 값을, pH는 시공간적 변동이 가장 심하였다. 표층퇴적상은 SWZ에서는 니질(Mud)함량이 높았으며 BWZ에서는 사질(Sand)함량이 높게 나타났고 FWZ에서는 사질(Sand)이나 자갈(Gravel)함량이 높게 나타났다. 그 외 유기물함량과 황화물량은 SWZ에서 높은 값을, Chl-a 량은 FWZ에서 높은 값을 보였다. 조사해역은 염도가 낮으며 유기물 함량, 황화물량이 낮고 조립한 퇴적상을 보이는 Fresh Water Zone과 염도가 높으며, 유기물함량, 황화물량이 높고, 세립한 퇴적상을 보이는 Saline Water Zone으로 조사지역의 환경이 뚜렷이 대비됨을 보여주고 있다. 섬진강 하구역에서 출현한 저서다모류의 출현종수와 서식밀도는 Salline Water Zone에서 가장 높았으며, Brackish Water Zone으로 갈수록 점점 감소하였고, Fresh Water Zone에서 매우 낮았다. Brackish Water Zone의 경우 서식밀도의 계절 변동이 매우 심하였는데, 이는 Prionospio cirrifera의 극우점 출현에 의한 것이다. 섬진강 하구역에서 출현한 저서다모류 중 매 계절 상위 5.0%의 점유율을 보이는 우점종은 총 6종이었다. 이 중 Lumbrineris longifolia, Prionoispio cirrifera, Tharyx sp.는 매 계절 주요 우점종으로 출현하였다. 그 외에 Hediste sp., Praxillella affinis, Tylorrhynchus sp.가 조사 시기에 따라서 우점종으로 출현하기도 하였다. 우점 출현 다모류들은 특징적으로 분포하는 해역이 뚜렷이 구분되었다. Saline Water Zone의 대표적인 종은 Lumbrineris longifolia, Tharyx sp., Mediomastus sp.이었다. Saline Water Zone에서부터 Brackish Water Zone까지의 해역에 폭넓게 걸쳐 출현하는 종은 Prionospio cirrifera, Aricidea sp., Heteromastus filiformis이었다. 그리고 Brackish Water zone의 내륙쪽 정점 일부와 Fresh Water Zone에서는 특징적으로 Tylorrhynchus sp., Hediste sp.가 우점 출현하였다. 섬진강 하구역에서 채집된 저서다모류의 출현종 조성과 정점간 유사도지수에 근거하여 집괴분석(Cluster Analysis) 및 비계량적 다차원척도법(non-metric Multidimensional Scaling)을 실시한 결과, 모든 계절에서 Saline Water Zone과 Fresh Water Zone에 위치하는 정점들은 각각 대표적인 하나의 정점군으로 구분되었다. 반면 Brackish Water Zone의 경우는 계절에 따라 수개의 정점군으로 세분되었다. 저서환경 요인과 저서다모류군집의 생태학적 요인들 간의 Pearson 상관관계분석과 주성분분석(PCA) 결과, 염도, 퇴적상, 유기물함량, DO 등이 저서다모류군집의 제반 생태학적 지수(출현종수, 서식밀도, 주요 종의 출현량, 생태지수)의 공간 분포를 결정짓는데 매우 중요한 역할을 하는 환경요인임이 확인되었다.

• 한국환경과학회지
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• 제3권4호
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• pp.333-348
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• 1994

The groundwater levels at 11 sites and the vertical variations o( the water Quality at 1 site were measured to study the characteristic of the groundwater level fluctuation of Cheju Island. The results of the measurements for the groundwater levels were as follows; In the eastern part, inculding Kimnyong, Jongdal and Sungsan, a sinusoidal fluctuation of groundwater levels occurred in response to oceanic tides. The tidal effect on the groundwater level was reduced depending upon the distance from seashore. But time lag showed that the trend is reversed. However, in the Samyang, Kosan and Shinhyo areas show that the groundwater level was directly influenced by the amount of precipitation. Especially, Shinhyo area which southern part in Cheju was affected the most and show upper parabasal groundwater level. In Susan- I which eastern part in Cheju, well rovealed that water Quality changed with the period of a tide. Salinity at the lim, bellow the natural groundwater level, was approched to the brackish groundwater(1000ppm).

• Ocean and Polar Research
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• 제28권3호
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• pp.305-315
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• 2006

In order to examine the transition of zooplankton community by the Saemangeum sea dyke, the temporal and spatial distribution of zooplankton community with relation to environmental variables was investigated using data collected in 2004 and 2005. Sixty-one zooplankton taxa were identified. Average abundance (except Noctiluca scintiliam) ranged from 236 to 1810 indiv. $m^{-3}$, and was the highest in May 2005 and the lowest in february 2005. Dominant species were Acartia hongi and Paracalanus indicus, and cirripedia nauplii and zoea were dominant groups. After the closure of the 4th sea dyke, brackish species such as Tortanus derjugini and Pseudodiaptomus inopinus are widely distributed while the abundance of N. scintillans decreased in the northern area inside the dyke. In canonical correspondence analysis (CCA) for examining the relationships among zooplankton, stations and environmental variables, the northern area inside the dyke was distinguished from the other areas and was represented by Acartia spp, and brackish copepods.; Also, this area was characterized by high chlorophyll a concentration and COD, and low diversity.

• Ocean and Polar Research
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• 제43권2호
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• pp.73-88
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• 2021

The community structure and health status of macrobenthos assemblages were investigated in the subtidal area of the Nakdong River estuary, Southern Coast of Korea. Benthic fauna samples were collected seasonally at 8 stations in the subtidal area of the Nakdong River estuary from February 2013 to October 2015. During the survey, a total of 380 species and 4,603 ind./m² of macrobenthos in all sampling areas were collected. The major dominant species were the polychaetes Minuspio japonica, Pseudopolydora kempi, Heteromastus filifomis, Capitella capitata, the amphipod Grandidierella japonica and the bivalvia Arcuatula senhousia. Some species of polychaetes found in the study area consisted of opportunistic species that showed high densities when habitat condition was poor. On the other hand, macrobenthos assemblages in the study area were divided into brackish water and marine groups. Abundance was high in the brackish group, while the number of species and diversity index were high in the oceanic group. The three indices (AMBI, M-AMBI, and BHI) in the assessment of health levels based on the ecological characteristics and number of species in macrobenthic were commonly shown to be in good condition in the group of oceanic stations, while relatively poor conditions were reflected in the group of brackish stations. Compared to other indices, the M-AMBI index of the three indices for health assessment was considered to be a relatively more suitable one to assess benthic ecological conditions.

• 생태와환경
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• 제55권4호
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• pp.406-414
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• 2022

Bolboschoenus planiculmis has been acknowledged as a key species in whooper swans (Cygnus cygnus) habitat by providing food for this migratory waterfowl. B. planiculmis wetlands are being degraded by water shortages and salinization caused by anthropogenic activities and climate changes. In 2004, the distribution of B. planiculmis in the tidal flats of the Nakdong Estuary was 2,475,568 m², and in 2021, the distribution area was 798,731 m², which decreased by 32.3%. In order to restore the degraded B. planiculmis wetlands, shoot transplantation and seed sowing were tentatively used in three places with different salinity and water levels. The average density per unit area in September at the optimal growth period after planting were A (fresh water level 50 cm) 58±15.65 m^-2, B (brackish water level 0~5 cm) 188±63.83 m^-2, C (brackish water level 0 cm or less) 188±45.13 m^-2. The tubers were observed as A 0 g dw m^-2, B 25.32±2.94 g dw m^-2, and C 13.39±0.91 g dw m^-2. Tubers were distributed in the soil, with only 3.0% at the 10~20 cm depth but 97.0% at the 0~10 cm depth. In contrast, the germination rate of B. planiculmis seeds was observed to be 0%. Results of this study provide technical support for the restoration of B. planiculmis wetland and the improvement in the quality of whooper swans habitat.

• 한국해양학회지
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• 제17권1호
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• pp.1-11
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• 1982

A study on the community and distribution of phytoplankton of the Kum River Estuary has been done in fall, 1980 and spring, 1981. Ond hundred and one taxa representing 22 families, 41 genera, 107 species, 2 varieties, and 2 forms were identified. The community of the study area composed mainly of diatom species icluding the very small fraction of dinoflagellates, blue-greens and greens. The dominant species were Skeletonema costatum, Paralia sulcata, and Asterionella kariana. The total standing crop of phytoplankton of winter samples was 115,000 cells/1 in average and that of spring samples was, 1,320,333 cells/1 in average. Of the representative members, dominant species above appeared moree than 10% of the total standing crop, Skeletonema costatum being maximized up to 46%. In spring Asterionella japonica, Thalassionema nitzschioides, and Chaetoceros curvistetus appeared 3∼8%, and Thalassiosira excentricus 3% in winter. The distribuion of marine forms showed negative correlation with that of fresh water forms, although the brackish-water forms showed no relationship. This change pattern of marine, brackish and fresh-water forms are discussed with the results of time series analysis. A list of phytoplankton species observed in this study is added.