• Ocean Science Journal
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• 제43권1호
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• pp.9-16
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• 2008

Environmental qualities of coastal water and bottom sediment were assessed at Jordan's northernmost tip of Gulf of Aqaba to evaluate possible impacts of the bordering fish pen cages in Eilat. Results showed significant differences between surface and bottom water in the chemical and physical variables in the different months of the year (2004-2005). Chlorophyll a was also significantly higher in bottom water when compared to that of the offshore water. Nitrate and ammonia were significantly higher in bottom water than the surface water at each individual station. The upper 2 cm of sediment sample recorded higher values of total phosphorus and organic matter. Seasonality affected the content of total phosphorus, organic matter, redox potential and color especially at the sediment layer below 3 cm of the sediment core. The present investigation showed slight modification of water and sediment qualities but no clear sign of eutrophication was observed. However, to maintain sustainability of healthy environmental conditions at the northern tip of Gulf of Aqaba potentials of any possible environmental risks arising from the fish farms or any other coastal investment should be carefully considered.

• 한국화재소방학회논문지
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• 제19권4호
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• pp.87-92
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• 2005

본 연구는 파스콘 제품에 사용되고 있는 기존의 할로겐계 난연제를 효과적으로 대체할 수 있는 난연제를 선정하여 파스콘 제품의 물성 저하를 가져오지 않으며, base polymer와의 혼합성 및 원료의 분산성 향상으로 난연성, 물성 향상 및 경제성이 확보된 파스콘을 제조하고 난연성을 평가하였다. 실험결과 적인 계 난연제는 5phr의 적은 첨가량으로도 높은 난연특성을 나타내었으며, 난연보조제로서 수산화금속화합물인 magnesium hydroxide(MH)를 2.5phr 첨가하였을 때 파스콘의 난연성에 상당한 효과가 있었으며, 주 난연제만을 사용했을 경우 발생했던 용융낙하 현상이 현저하게 줄어듦을 확인할 수 있었다.

• 한국토양비료학회지
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• 제13권3호
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• pp.93-97
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• 1981

4종(種)의 제주도 토양에 인산질비료(燐酸質肥料)를 시용(施用)한후 무기태인산(無機態燐酸)의 형태별(形態別) 함량변화와 수종 침출액(浸出液)에 의한 유효인산(有效燐酸) 침출량(浸出量)을 실내실험으로 조사(調査)하여 비교(比較) 검토한 결과(結果)는 다음과 같다. 1. 총인산에 대한 무기태인산(無機態燐酸)의 비율(比率)은 토양종류에 따라 달라 Al-P는 6.9-28.8%, Fe-P는 24.1~26.9%, Ca-P는 7.4~11.9% 범위이며 유효인산(有效燐酸)은 0.7-8.0%로 매우 낮았다. 2. 토양종류별로 인산(燐酸)을 시용(施用)한 후(後) 60일후(日後)에 조사(調査)한 토양인산의 형태별(形態別) 조성(組成)을 본 결과(結果) 흑색토(黑色土)에서는 Al-P>Fe-P> Ca-P, 농암갈색토(濃暗褐色土)에서는 Fe-P> Al-P> Ca-P, 암갈색토(暗褐色土)에서는 Fe-P> Ca-P> Al-P. 적황색토(赤黃色土)에서는 Fe-P> Al-P> Ca-P의 순(順)으로 나타나 토양별 차이(差異)가 있었다. 3. 5종(種)의 침출액(浸出液)으로 토양별 유효인산(有效燐酸)을 검정한 결과(結果) Bray No.2법(法)은 토양종류에 관계없이 어느 토양에서나 침출능(浸出能)이 컸으나 그 외의 방법(方法)들은 토양의 종류별(種類別)로 침출능(浸出能)이 상이(相異)하게 나타났다. 4. 유효인산(有效燐酸) 침출방법(浸出方法)과 무기태인산(無機態燐酸) 함량(含量)과의 관계에서 Bray No.2법(法)은 Ca-P와 5%수준에서, Olsen법(法)은 Al-P, Fe-P, Ca-P 및 Total-P와 각각 1%수준에서 유의(有意)한 관계를 보였다.

• 한국토양비료학회지
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• 제47권3호
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• pp.147-154
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• 2014

Consecutive pepper cultivation in plastic film houses may lead to salt accumulation because pepper is considered a heavy nutrient feeder. For this reason, appropriate methods of fertilizer application should be established. Thus, we investigated the effect of different intervals of side-dressing N and K fertilizer applications on soil and red pepper in a plastic film house. All the amounts of recommended compost and phosphorus fertilizer were applied as basal dressing. Cultivars of the pepper plant were Cheon-Ha-Dae-Se (CHDS) and NW-BiGaLim (NW-BGL). Nitrogen and potassium fertilizers were treated as side-dressing at different intervals, 22 times in every 10 days, 15 times in every 15 days, and 11 times in every 20 days. Soil pH decreased with decreasing the intervals of side-dressing applications, whereas electrical conductivity (EC) declined with the increasing fertilizer application intervals. In particular, EC value decreased by up to 75% with CHDS cultivar in the plot of 20 day-interval and with NW-BGL cultivar in the plot of 15 day-interval. The concentrations of available phosphorus in the soils increased with increasing the interval. The concentration of exchangeable $K^+$ increased but exchangeable $Ca^{2+}$ and $Mg^{2+}$ decreased in all the plots, except in the control plot. The concentrations of nitrogen and phosphorus in leaves of the pepper plants were lowest in the control plot. Potassium concentrations in the pepper leaves were high in the control plot and in the plots of CHDS with 10 day-interval and NW-BGL with 15 day-interval. Red pepper productivity was high in the plots of 10- and 15 day-intervals for CHDS cultivar and 15- and 20 day-intervals for NW-BGL cultivar. Therefore, the 15 day-interval of side-dressing N and K applications was considered as an appropriate method for cultivating pepper plants and protecting soil in plastic film houses.

• 한국해양학회지:바다
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• 제15권1호
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• pp.16-24
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• 2010

Skeletonema costatum, Chaetoceros didymus, Alexandrium tamarense 그리고 Heterosigma akashiwo의 인 제한에 따른 용존태 유기인(dissolved organic phosphorus; DOP)의 이용성과 alkaline phosphatase(APase)의 활성을 살펴보기 위해 실내실험을 실시하였다. S. costatum, C. didymus, A. tamarense 그리고 H. akashiwo는 인 공급원으로써 용존태 무기인 (dissolved inorganic phosphorus; DIP) 이외에 phosphomonoester와 nucleotide 화합물을 이용하여 성장을 유지할 수 있었다. S. costatum, C. didymus, A. tamarense 그리고 H. a/wshiwo의 APase 활성은 배양액내의 DIP가 각각 $0.30\;{\mu}M$, $0.33\;{\mu}M$, $2.04\;{\mu}M$과 $0.63\;{\mu}M$에서 최초로 활성을 보였으며, 최대활성은 각각 $0.01\;pmol\;cell^{-1}\;hr^{-1}$, $0.11\;pmol\;cell^{-1}\;hr^{-1}$, $1.63\;pmol\;cell^{-1}\;hr^{-1}$와 $0.19\;pmol\;cell^{-1}\;hr^{-1}$였다. APase 활성은 종에 따라 다르게 나타났지만, 최대 활성은 DIP의 흡수속도보다도 높아 인이 제한된 환경에서 효과적으로 DOP를 가수분해하여 성장을 유지 할 수 있을 것으로 보인다. 따라서 DOP의 이용능력은 적조 플링크튼의 성장뿐만 아니라 종간경쟁에도 기여할 것으로 생각된다.

• ALGAE
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• 제21권4호
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• pp.433-443
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• 2006

This study was performed to understand the morphological and ecological characteristics of Peridinium bipes var. occultatum Lindem., which is the organism responsible for freshwater red tides in Sangsa dam and Miryang dam reservoirs. The samples were collected from April to July 2004 when the freshwater red tides occurred. In the study, we were able to differentiate P. bipes var. occultatum from P. bipes, a closely related species, by its smaller antapical horn size. In Miryang dam reservoir the red tide occurred only within the area of the upstream, but it was well developed in all of the water area in Sangsa dam reservoir. In 2004 average LTSI (Lake Trophic Status Index; Yang and Dickman, 1993) of Miryang dam reservoir was 3.53 of mesotrophic state and Sangsa dam reservoir was 8.59 of eutrophic state. It was determined, through culture experiments under various conditions that vitamins, trace elements, phosphorus and nitrogen were important contributing factors to the growth of P. bipes var. occultatum. A rapid toxic effect of P. bipes var. occultatum on aquatic organisms such of Daphnia magna and Oryzias latipes was not identified in this study.

• 한국환경농학회:학술대회논문집
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• 한국환경농학회 2011년도 30주년 정기총회 및 국제심포지엄
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• pp.188-195
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• 2011

Red lateritic soils are typically low in total organic carbon (TOC) and available phosphorus (AP) content and continuous fertilization is required to obtain desired crop yield. In this experiment, cattle manure in three forms (air-dried, composted and vermicomposted) were applied to red lateritic soil to study their effect on TOC and AP content of soil and probable mechanism of P-solubilization as affected by these treatments were also studied. Vermicompost was the most effective to solubilize insoluble P in red lateritic soil (Alfisols) as compared to other organic amendments (air-dried cattle manure and compost). The highest SPA in vermicompost-treated soil attributed to the comparatively higher concentration of all the three SPA isozymes in these soils. The maximum P-solubilization in these soils might be attributed to the highest SPA and presence of several organic acids like citric, lactic and oxalic acids in vermicompost-treated soils. Since, vermicompost application also increased TOC, mineralizable N and exchangeable K content of soil, vermicompost could be considered as the most rational organic amendment to improve chemical properties of red lateritic soils.

• 한국토양비료학회지
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• 제49권6호
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• pp.669-676
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• 2016

A field study was conducted to determine the runoff loss of N and P in small scale of red pepper field plots (10% slope), consisting of three different plots with black polyethylene vinyl mulching (mulching), ridge without mulching (ridge), and flat without ridge and mulching (flat). Composted manure and urea as a basal application were applied at rates of $20MT\;ha^{-1}$ and $93kg\;N\;ha^{-1}$, respectively. Urea at $189kg\;N\;ha^{-1}$ and fused phosphate at $67kg\;P_2O_5\;ha^{-1}$ were additionally applied on June 25 with different fertilization methods, broadcast application in flat plot and hole injection in ridge and mulching plots. Plant uptake of N and P was positively correlated with their respective concentrations in surface soil: mulching > ridge > flat plots. The runoff loss by soil erosion was higher in flat plot than ridge and mulching plot with contour line. Nitrate loss by the runoff water had no significant differences among three surface management practices, but the higher average value in ridge and mulching plots than flat plot. Especially, the flat plot had no phosphate loss during summer season. This is probably due to low labile P content in surface soil of flat plot. In the summation of soil and water loss, flat plot was higher in N and P loss than ridge and mulching plot with contour line. Nevertheless, the nitrate and phosphate loss by runoff water could be more important for non-point source management because the water could meet the river easier than eroded soil because of re-deposition around slope land.

• Journal of Nutrition and Health
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• 제34권8호
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• pp.881-886
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• 2001

The purpose of this study was to Investigate the effects of green tea catechin on changes of mineral contents in chronic cadmium-poisoned rats. Sprague-Dawley male rats weighing 100 $\pm$ 10g were randomly assigned one of normal group and three cadmium poisoned groups. Cadmium groups were classified to catechin free diet(Cd-0C group), 0.25% catechin diet(Cd-0.25C group) and 0.5% catechin diet(Cd-0.5C group) according to the levels of catechin supplement. Animals were raised for 20 weeks. Cadmium was supplied in drinking water which contained 50ppm Cd$^{2+}$. Effects of catechin were analyzed on changes of mineral contents in chronic cadmium poisoned rats by determining the calcium accumulation in bones, blood, urine and faces and phosphorus In blood and urine. Cd-poisoning inducted the decrease of red blood cell(RBC), white blood cell(WBC), contents of blood hemoglobin and hematocrit, but the levels of those indices were increased by catechin supplementation. The contents of tibia and femur in Cd-0C group was significantly lower than in normal group, but those of catechin supplemetation group was similar to normal group. The calcium contents of urine and faces were higher in Cd-poisoned groups than in normal group, but they was lowered by catechin supplementation. The phosphorus contents of blood and urine in Cd-0C group was significantly lower than in normal group, but that of catechin supplementation group was similar to normal group. Catechin supplementation improved the calcium metabolism in chronic cadmium poisoned rats by increasing the contents of minerals such as calcium and phosphorus in blood and femur and by lowering the urinary and fecal calcium.m.

• 한국작물학회지
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• 제50권2호
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• pp.112-119
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• 2005

The effects of Rhizobium inoculant, nitrogen, phosphorus, and molybdenum on nodulation, dry matter production, yield attributes, pod and seed yields, protein and phosphorus contents in seed of pea (pisum sativum) var. IPSA Motorshuti-3 were assessed by a field experiment. Among the treatments Rhizobium inoculant in combination with 25kg P and 1.5kg Mo/ha performed best in recording number of nodules/plant, total dry matter yield, number of pods/plant, number of seeds/pod, 1000-seed weight, green pod yield, green and mature seed yields of pea. The highest green pod yield of 15.37 t/ha ($97.05\%$ increase over control) and green seed yield of 9.6t/ha ($69.31\%$ increase over control) were obtained by inoculating pea with Rhizobium inoculant in association with 25kg P and 1.5 Mo/ha. The effects of 60 or 120kg N/ha were comparable to Rhizobium inoculant in most cases. There were positive correlations among yield attributes, yield, protein and phosphorus contents in seeds of pea. From the viewpoint of yield attributes, yield, and seed quality, application of Rhizobium inoculant along with 25kg P and 1.5kg Mo/ha was considered to be the balanced combination of nutrients for achieving the maximum output from cultivation of pea in Shallow-Red Brown Terrace Soil of Bangladesh.