• 제목/요약/키워드: Salinity decrease

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The Effect of Salinity (NaCl) on the Germination and Seedling of Sugar Beet (Beta vulgaris L.) and Cabbage (Brassica oleracea L.)

  • Jamil, M.;Rha, Eui-Shik
    • Plant Resources
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    • 제7권3호
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    • pp.226-232
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    • 2004
  • This study was carried out to investigate seed germination and seedling of cabbage and sugar beet in four treatments of salinity including 0 (control), 0.5, 1.0 and 1.5% NaCl. The results showed that different treatments of salinity had considerable effects on the germination and root and shoot length of cabbage and sugar beet. Percent of germination in both species showed significant decrease with increasing salinity up to 1.5% NaCl. This decrease was more evident in cabbage when compared to sugar beet. The required time for germination increased with high levels of salinity. The seedling growth of both species were inhibited by all salinity levels. Particularly at 1.0 and 1.5% NaCl, no measurable length was observed in cabbage and sugar beet. At 0.5% NaCl root growth of both plant species was more affected as compared to shoot growth by salinity.

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여름철 남해의 저염화와 수송양 (Salinity Decrease and the Transport in the South Sea of Korea in Summer)

  • 조양기;김구;노홍길
    • 한국해안해양공학회지
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    • 제7권1호
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    • pp.126-134
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    • 1995
  • 국립수산진흥원이 관측한 염분자료를 분석하여 여름철 남해의 저염화 현상을 규명하였다. 6월과 8월에 남해 전 수심의 저염화는 강수량과 강물의 유입으로는 설명될 수 없고, 주위 해역 중 유일하게 저염수가 존재하는 제주해협 서편 해역 저염수의 유입으로만 설명이 가능하다. 염보존 Box 모델의 결과에 의하면, 대한해협 서수도의 수송량을 1.4-2.0$\times$$10^{6}$ ㎥/sec이라고 할 때, 이 수송량의 31-36% 정도인 0.5-0.6$\times$$10^{6}$ ㎥/sec(평균유속은 10-13cm/sec)의 수송량이 제주해협을 경유하여 남해로 유입되고, 나머지는 제주도와 대마도 사이로 유입된다.

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서산 간척지의 염도와 벼의 생육에 관한 연구 (Studies on Salinity and Growth of Rice at Seosan Reclaimed Land)

  • 이희선;김옥봉
    • The Korean Journal of Ecology
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    • 제20권5호
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    • pp.367-373
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    • 1997
  • The effects of salinity on the growth and production of rice were studied at Seosan reclaimed land from July to October, 1995. The plant height, the number of living aleaves, dead leaves and total leaves, the number of the grains and the dry weight of the grains per individual, and the dry weight of above the ground in $25cm{\times}25cm$ quadrat were investigated on 5 plots whers were different salinity. The plant height, the number of living leaves and total leaves and the number of grains and the dry weight of grains per individual, and the dry weight of above the ground decreased as the salinity of water increase and the number of dead leaves of rice increased as the salinity of water decrease. The effect of salinity on the reproductive production is severer than the vegetative production. Because of the salinity, the growth and the production of the rice at Seosan reclaimed land are worse than the normal rice field.

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SBR공정에서 영양염류 제거에 대한 염분의 영향 (The Effect of Salinity on Biological Nutrient Removal in SBR)

  • 송창수;오준성
    • 한국물환경학회지
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    • 제18권3호
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    • pp.237-243
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    • 2002
  • The effect of a salinity on the performance of a biological nutrient removal system was investigated using a model SBR(Sequencing Bach Reactor) system. The system was operated at a 12hr, 18hr, 24hr, and 36hr HRT with a salinity level of 20,000mg/L and compared with a system similarly operated with fresh water. The influent salinity level of 8,000 mg/L does not have a significant effect on BOD removal efficiency, there is a noticeable decrease in BOD removal rate from 10,000 mg Cl-/L. The Nitrogen could be removed from the saline wastewater with the same efficiency as for the fresh water because of low C/N ratio in anoxic period. The excess biological phosphorous removal is highly affected by the increase in the influent salinity. The efficiency is decreased from 96.6% to 43.4% when the influent salinity is increased from 0 to 20,000mg/L.

빠른 염분변화가 Striped bass 잡종 (Morone Chrysops male X Msaxatilis female)의 생리적 반응과 생존에 미치는 영향 (Effects of Acute Change of Salinity on Physiological Response and Survival in Hybrid Striped Bass (Morone Chrysops male X Msaxatilis female))

  • 임한규;이종하;정민환;한형균;임영수;이정호;이병철
    • 한국수산과학회지
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    • 제37권2호
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    • pp.116-121
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    • 2004
  • Physiological responses and tolerance limit of hybrid striped bass $(Morone\;Chrysops\;male{\times}\;M.\;saxatilis\;female),$ were investigated on salinity changes from 33 psu to 0 psu and from 0 to psu 33 psu in two separate trials, respectively. In the acute salinity decrease from sea water (33 psu) to fresh water (0 psu), plasma level of cortisol, glucose, total protein, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were not affected, however, $Na^+,\;Cl^-$ and osmolality significantly decreased. In the acute salinity increase from fresh water to sea water (33 psu), plasma cortisol level did not change. Glucose and total protein concentrations in plasma and hematocrit (Hct) decreased, whereas AST, ALT, $Na^+,\;Cl^-$ and osmolality increased. The hybrid striped bass can overcome the acute changes of salinity, from 0 psu to 33 psu or from 33 psu to 0 psu, But salinity decrease stressed the fish much more than salinity increase.

어린이급식관리지원센터 등록 시설 국물음식의 염도 모니터링 (Salinity Monitoring of Soups of The Institutions Enrolled at Center for Children's Foodservice Management)

  • 박현내;김순미
    • 동아시아식생활학회지
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    • 제26권6호
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    • pp.507-516
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    • 2016
  • 본 연구는 지속적인 염도 관리의 교육효과를 살펴보기 위하여 강동구 어린이급식관리지원센터에 등록된 21인 이상의 어린이집에서 제공되는 국물음식의 염도를 모니터링 하였으며, 그 결과는 아래와 같다. 1. 모니터링을 실시한 시설은 1차 102개소, 2차 76개소, 3차 78개소이며, 맑은 장국, 된장국, 곰국, 찌개, 기타로 구분한 국물음식의 평균 염도는 1차(0.45%), 2차(0.41%), 3차(0.39%)로 진행됨에 따라 유의적으로 감소하였다(p<0.01). 2. 어린이집 유형에 따른 염도는 국공립어린이집의 경우, 1차 0.43%, 2차 0.35%, 3차 0.38%로 유의적인 감소를 나타내지는 않았으나, 민간어린이집은 1차 0.46%, 2차 0.43%, 3차 0.39%로 모니터링을 진행할수록 유의적으로 감소하였다 (p<0.01). 3. 집단급식소 등록 여부에 따라 급식 인원 50인 이상의 대규모 급식소와 50인 미만의 소규모 급식소의 염도를 비교한 결과, 대규모 급식소의 국물음식의 평균 염도가 낮았으나 유의적인 차이를 보이지 않았으며, 모두 1차에 비해 3차의 평균 염도가 감소하는 경향을 나타냈다. 4. 3차에 걸친 모니터링 시 어린이집에서 제공한 국물음식의 횟수는 총 256회였으며, 이 중 맑은 장국이 139회로 가장 많이 제공되었고, 된장국이 76회, 기타(들깻국, 수제비 등) 24회, 찌개 9회, 곰국 8회 순서로 나타났다. 5. 국물음식의 종류별 염도는 곰국을 제외하고는 맑은 장국, 된장국, 찌개 모두 1차에서 3차로 진행될수록 염도가 감소하였으나, 국의 종류 및 모니터링 차수에 따른 염도의 유의적인 차이는 없었다. 그러나 동일한 국물음식 간에도 염도의 차이가 매우 커서 개별 국물음식의 최소치와 최대치의 차이는 1차의 경우 달걀국이 0.62%, 2차는 감잣국이 0.54%, 3차는 양송이국이 0.64%를 나타냈다. 본 연구 결과, 지속적인 염도 모니터링 진행을 통해 어린이집 국물음식의 염도가 낮아지는 것으로 나타나, 센터에서 진행하는 교육의 효과를 확인할 수 있었다. 영유아 급식시설에서의 국물음식의 염도 기준은 명확하게 제시되어 있지 않으나, 식품의약품안전처에서는 성인의 경우 0.6% 이하, 영유아 급식시설에서는 이보다 더 낮은 0.5% 이하로 관리하도록 권고하고 있다. 그러나 적정 염도는 음식의 종류에 따라 다르므로 영유아를 위한 주요 나트륨 급원 메뉴의 적정 염도범위를 설정할 필요가 있다. 또한 본 연구에서 3차에 걸쳐 조사된 국물음식의 전체 염도 평균치는 모두 0.5% 미만으로 적절한 범위에서 관리하고 있었으나, 개별 국물음식의 염도는 매우 큰 차이를 나타내었다. 영유아는 미각이 형성되는 시기이며, 염도는 음식에 대한 기호에 영향을 줄 수 있으므로 국물음식의 염도는 일정한 범위 내에서 관리되는 것이 바람직하며, 추후 최고 염도뿐만 아니라, 음식의 맛과 건강을 함께 고려하는 최저 염도에 대한 논의도 함께 이루어져야 할 필요가 있을 것으로 사료된다.

Plasma Stress Responses in Juvenile Red-Spotted Grouper (Epinephelus akaara) exposed to Abrupt Salinity Decrease

  • Lee, Jang-Won;Kim, Hyung Bae;Baek, Hea Ja
    • 한국발생생물학회지:발생과생식
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    • 제20권3호
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    • pp.187-196
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    • 2016
  • The objective of the current study was to determine acute plasma stress responses in two size groups of juvenile Epinephelus akaara (average body weight: $8.4{\pm}2.1$ and $3.3{\pm}0.6g$; 150 and 120 days after hatch, respectively) exposed to abrupt salinity drops (from 34 practical salinity unit, PSU seawater to 18, 10 PSU (experiment 1) or 26, 18, 10 PSU (experiment 2), respectively). Plasma glucose, glutamic oxalate transaminase, glutamic pyruvate transaminase, red blood cell counts, and gill histology were determined during 72 h exposure. Significantly increased plasma glucose, glutamic oxalate transaminase levels, and red blood cell counts were observed in fish exposed to 18 or 10 PSU. Histological changes, such as hyperplasia and lifting of epithelium in the gill secondary lamellae, were also observed in fish exposed to 18 or 10 PSU at 72 h post-drop. E. akaara exposed to sudden salinity drops to 18 or 10 PSU still seems to undergo the primary adjustment phase before fish reaches a new homeostasis, whereas fish exposed to 26 PSU seems to mount osmotic changes. Therefore, the no observed adverse effect levels for 72 h acute salinity challenge was 26 PSU in our study, and salinity drop to 18 PSU and below can possibly cause acute adverse effect, in which fish could be vulnerable to additional stresses such as a temperature changes or handling stress.

안양지역 어린이집에서의 블루투스 염도계 사용에 따른 국의 염도 비교 (Comparison of Salinity of Soups on the Use of Bluetooth Salinity Meter at Childcare Centers in Anyang Area)

  • 김혜원;피재은
    • 문화기술의 융합
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    • 제6권4호
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    • pp.435-443
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    • 2020
  • 이 연구는 블루투스 염도계 사용이 어린이집에서 제공하는 국의 적정 염도 수준을 조절하는 데 영향을 미칠 수 있는지 확인하고자, 2019년 1월부터 12월까지 안양시 어린이급식관리지원센터에 등록된 어린이집 중 나트륨 저감화 특화사업에 참여를 희망하는 어린이집(블루투스 염도계 사용 군, BG)과 참여하지 않은 어린이집(블루투스 염도계 미사용군, NG)을 대상으로 실시하였다. 연구 결과, 블루투스 염도계 사용 여부에 따라 국의 염도와 나트륨양을 비교하였을 때, BG의 값이 NG보다 유의하게 낮았으며, 블루투스 염도계의 사용 횟수가 증가함에 따라 염도와 나트륨양이 감소하였다. 결론적으로, 블루투스 염도계는 어린이집에서의 나트륨 저감화 교육과 관련하여 조리원들의 자발적인 염도 조절을 유도하는 수단으로 활용 가능할 것으로 사료된다.

Why the Mediterranean Sea Is Becoming Saltier

  • Bryden, Harry-L.;Boscolo, Roberta
    • Journal of the korean society of oceanography
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    • 제37권3호
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    • pp.117-124
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    • 2002
  • Anthropogenic changes have been made to the water budget for the Mediterranean Sea as a result of river diversion projects. The decrease in freshwater inflow to the Mediterranean represents an effective increase in the overall net evaporation over the basin. Hydraulic control models for the exchange between the Mediterranean and Atlantic through the Strait of Gibraltar predict that the salinity of the Mediterranean should increase if the net evaporation over the Mediterranean increases. Increases in the salinity of the deep waters in both the western and eastern Mediterranean basins have been observed. The causes of such higher deep water salinity are attributed to increases in intermediate water salinity which are ultimately mixed down into the deep sea during wintertime buoyancy loss events. The pattern of the Mediterranean salinity increase is instructive for understanding how the water mass properties in a basin change over time as a result of anthropogenic changes.

Distribution Pattern of Zooplankton in the Han River Estuary with respect to Tidal Cycle

  • Youn, Seok-Hyun;Choi, Joong-Ki
    • Ocean Science Journal
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    • 제43권3호
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    • pp.135-146
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    • 2008
  • The monthly distribution of zooplankton communities in Han River estuary was investigated at two stations from July 1998 to June 1999. Monthly mean abundance of total zooplankton varied remarkably, with the range from 20 $indiv.{\cdot}m^{-3}$ to 19,600 $indiv.{\cdot}m^{-3}$. During the study period, dominant species of zooplankton community were dinoflagellate Noctiluca scintillans, copepods Paracalanus indicus, Paracaanus crassirostris, Acartia hongi, Acartia ohtsukai, and meroplanton cirriped larvae. According to tidal states, relative high abundance occurred at high tide without regard to season. The temporal distribution of abundance implied that the reduced salinity probably limited the zooplankton populations and the fluctuations of salinity were an important factor in the variation of abundance. However, the results of salinity tolerance test shows that the variations in salinity do not directly influence the decrease of abundance. This study shows that the relatively high abundance of zooplankton near high tide seems to be related with the expansion of abundant zooplankton inhabiting Incheon coastal waters through tidal currents.