• Title/Summary/Keyword: inorganic nutrients

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Studies on Extrusion Procedures of Wheat Bran and Dietary Levels of Phosphorus in Nutrients Availability of Broiler Chicks (육계용 병아리에서 밀기울의 사출과 인의 결여수준이 영양소의 이용성에 미치는 영향)

  • 김인호;김춘수
    • Korean Journal of Poultry Science
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    • v.17 no.4
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    • pp.284-295
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    • 1990
  • Dietary levels of 0%, 0225%, 0.45% inorganic phosphorus in the form of tricalcium phosphate were included in two different experimental diets, which contains 40% of wheat bran with or without extrusion. It is to examine the effects of extruded wheat bran containing different Bevels of inorganic phosphorus on the performance of broiler chicks, including the nutrient availabilities, compared with that of the diet containing non-extruded wheat bran. The results are as follows; 1. Regardless dietary levels of inorganic phosphorus, the weight gain in general was higher for the groups fed non-extruded wheat bran but little significance was seen between the groups of extruded and the non-extruded. However, the effect of dietary inclusion of inorganic phosphorus on the weight gain was evident and the gain was higher in the groups receiving the higher levies of inorgainc phosphorus but failed to observe the significant difference between the added groups of 0.225% and 0.45% of inorganic phosphorus, suggesting that a considerable amount of phytin phosphorus in wheat bran is available to meet the requirement. 2. For the feed intake, there was a tendency for the groups fed extruded wheat bran consuming more feed, compared with that of the non-extruded but little significance was observed. This was also true between the groups of receiving 0.225% and 0.45% inorganic phosphorus t The feed efficiency was improved by the addition of inorgainc phosphorus, but failed to observe the significance between the added groups. 4. The dry matter digestibility was improved in proportion to increasing the levels of inorganic phosphorus for the both groups of extruded and the non-extruded This indicates that addition of extruded wheat bran has little effects on improving the digestibility. 5. Within the added groups of 0.225% and 0.45% inorganic phosphorus, the protein digestibility was increased with including the extruded wheat bran in the diet However, the effect on body weight gain was not evident. 6. The calcium and phosphorus content of tibia was shown the tendency of increasing with increasing the dietary levels of inorganic phosphorus but close correlation with dietary levels of inorganic phosphorus was not noted in tibia contents of calcium and phosphorus.

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DISTRIBUTION CHARACTERISTICS OF NUTRIENTS IN CHINESE BOHAI SEA

  • Li, Zhengyan;Gao, Huiwang;Bai, Jie;Shi, Jinhui
    • Proceedings of the Korean Environmental Health Society Conference
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    • 2001.11a
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    • pp.19-29
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    • 2001
  • Nutrients are key environmental factors in marine ecosystem. They limit algal growth when at low concentrations and cause algal bloom when at high contents. They also control the growth and succession of many other biota including bacteria and zooplankton, either directly or indirectly. Nutrient contents therefore affect both the structure and functions of marine ecosystem. To study the contents and distribution of nutrients in Chinese Bohai Sea, two cruise surveys were undertaken in August 2000 (summer) and January 2001 (winter), respectively. A total of 595 water samples were collected from 91 sites. After collection the samples were transported to the laboratory and five nutrients, i.e., nitrate, nitrite, ammonia, phosphate and silicate, were analyzed. The results showed that tile average concentration of total inorganic nitrogen (TIN) in Bohai Sea in winter (6.5293.717 ${\mu}$mol$.$l$\^$-1/) was significantly higher than that in summer (3.717 ${\mu}$mol$.$l$\^$-1/). The phosphorus concentration in winter (0.660 ${\mu}$mol$.$l$\^$-1/) was also significantly higher than that in summer (0.329 ${\mu}$mol$.$l$\^$-1/). Mean silicate concentration in winter (7.858 ${\mu}$mol$.$l$\^$-1/) was not significantly different from that in summer (7.200 ${\mu}$mol$.$l$\^$-1/). Nutrients also varied considerable among different areas within Bohai Sea. TIN concentration in Laizhou Bay (4.444 ${\mu}$mol$.$l$\^$-1/), for example, was significantly higher than those in Bohai Bay (2.270 ${\mu}$mol$.$l$\^$-1/) and Bohai Straight (2.431 ${\mu}$mol$.$l$\^$-1/), which probably reflects tile discharge of large amounts of nitrogen into Laizhou Bay via Yellow River. The nutrients also showed vertical distribution pattern. In summer, nutrients in bottom layer were generally higher than those in surface and medium layers. In winter, however. nutrients in different layers were not significantly different Compared with historic data, TIN contents increased continuously since early 1980s, phosphorus arid silicone contents, nevertheless, fell down to some degree. Based on atomic ratios of different nutrients, nitrogen is still the main limiting factor for algal growth in Bohai Sea.

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Growth and community response of phytoplankton by N, P and Fe nutrient addition in around water of Ulleungdo and Dokdo in East Sea (동해 울릉도-독도해역에서 질소, 인, 철 첨가실험에 따른 식물플랑크톤의 성장 및 군집반응)

  • Baek, Seung Ho;Lee, Minji;Kim, Yun-Bae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.11
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    • pp.186-195
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    • 2016
  • We investigated phytoplankton and vertical inorganic nutrients at two stations around water of Ulleungdo and Dokdo in the East Sea, Korea. Nutrient addition experiments (+N, +P, +NP and +Fe) were also conducted to determine the growth response and nutrient consumption of the phytoplankton assemblage using the surface water of St. UD3 and St.50. In the field, although inorganic nutrients were low in the euphotic layer, these nutrients were increased at depths below 100 m. The total phytoplankton abundances in St. UD3 and St.50 were $4.9{\times}10^5cells\;L^{-1}$ and $1.9{\times}10^5cells\;L^{-1}$, respectively. The dominant species at St. UD3 was observed to be Raphidophyta Heterosigma akashiwo, Cryptophyta Crytomonas spp., and diatom Leptocylindrus danicus, while L. danicus and H. akashiwo including small diatom species Chaetoceros socialis were dominant at St. 50. In the nutrient addition experiments, phytoplankton growth (in vivo flourescence) in the +N and +NP treatment was 2-3 times higher than that in the +P treatment, indicating that the natural phytoplankton can respond to pulsed nutrient loading events. In addition, in vivo fluorescence in +Fe treatment was not statistically (p>0.05) different from that of the non-Fe treatments, indicating that the phytoplankton growth response in +Fe treatment was not significant. Dominant H akashiwo and L. danicus in the field showed a rapid response in nutrient additional bio-algal assay, particularly L. danicus in the +Fe treatments.

Inorganic Nutrient Inputs from Precipitation, Throughfall, and Stemflow in Pinus densiflora and Quercus mongolica Stands in an Urban Forest Ecosystem

  • Kim, Kee Dae
    • Journal of Environmental Science International
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    • v.28 no.10
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    • pp.813-829
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    • 2019
  • We measured the amount of precipitation, stemflow, and throughfall and concentrations of nine major inorganic nutrients ($H^+$, ${NH_4}^+$, $Ca^{2+}$, $Mg^{2+}$, $K^+$, $Na^+$, $Cl^-$, ${NO_3}^-$, and ${SO_4}^{2-}$) to investigate the nutrient inputs into soil from precipitation in Pinus densiflora and Quercus mongolica stands from September 2015 to August 2016. The precipitation inputs of $H^+$, ${NH_4}^+$, $Ca^{2+}$, $Mg^{2+}$, $K^+$, $Na^+$, $Cl^-$, ${NO_3}^-$, and ${SO_4}^{2-}$ into soil were 0.170, 15.124, 42.227, 19.218, 14.050, 15.887, 22.391, 5.431, and $129.440kg{\cdot}ha^{-1}{\cdot}yr^{-1}$, respectively. The P. densiflora stemflow inputs were 0.008, 0.784, 1.652, 1.044, 0.476, 0.651, 1.509, 0.278, and $9.098kg{\cdot}ha^{-1}{\cdot}yr^{-1}$, and those for Q. mongolica were 0.008, 0.684, 2.429, 2.417, 2.941, 1.398, 2.407, 0.436, and $13.504kg{\cdot}ha^{-1}{\cdot}yr^{-1}$, respectively. The P. densiflora throughfall inputs were 0.042, 21.518, 52.207 27.694, 20.060, 24.049, 37.229, 10.241, and $153.790kg{\cdot}ha^{-1}{\cdot}yr^{-1}$, and those for Q. mongolica were 0.032, 15.068, 42.834, 21.219, 20.294, 20.237, 24.288, 5.647, and $119.134kg{\cdot}ha^{-1}{\cdot}yr^{-1}$, respectively. Of the total throughfall flux (i.e., stemflow + throughfall flux) of the nine ions for the two species, ${SO_4}^{2-}$ had the greatest total throughfall flux and $H^+$ had the lowest. The net throughfall fluxes of the ions for the two species had various correlations with the precedent dry period, rainfall intensity, rainfall amount, and pH of precipitation. The soil pH under the Q. mongolica canopy (4.88) was higher than that under the P. densiflora canopy (4.34). The difference in the soil pH between the two stands was significant (P < 0.01), but the difference in soil pH by the distance from the stems of the two species was not (P > 0.01). This study shows the enrichments of inorganic nutrients by two representative urban forests in temperate regions and the roles of urban forests during rainfall events in a year.

An Experimental Study for the Falling Test and Upwelling Effect of the Artificial Upwelling Structures in Flow Field (흐름장에서 인공용승구조물의 블록투하 및 용승효과에 관한 실험적 연구)

  • Jeon, Yong-Ho;Lee, Gyung-Sun;Kang, Yoon-Koo;Ryu, Cheong-Ro
    • Journal of Ocean Engineering and Technology
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    • v.21 no.4
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    • pp.21-27
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    • 2007
  • The multiplication equipment of marine products with artificial upwelling structures could be useful in the fishing grounds near coastal areas. Artificial upwelling structures could move the inorganic nutrients from the bottom to the surface. Artificial upwelling structures have been used to improve the productivity of fishing grounds. Until now, research on artificial upwelling structures has been related to the distribution of the upwelling region, upwelling structures, and the marine environment. However, little work on the optimum design of the rubber-mound artificial upwelling structures has been done to increase the efficiency of drawing up the inorganic nutrients. This study investigated the optimum cross-section of rubber-mound artificial upwelling structures by means of hydraulic experiments. The hydraulic experiments include the falling test of rubber. Based on the results of the falling test, the relationship between the length of the rubber mound and water velocity, and the relationship between the shape of the rubber and the stratification parameter were established. In addition, the effect of the void ratio of various artificial structures on the stratification parameter was studied. From the experiment, it was found that upwelling could be enhanced when the ratio of structure height to water depth was 0.3 and stratification parameter was 3.0. The upwelling was not improved when the void ratio exceeded 0.43. The optimum size of rubber mounds was determined when the incident velocity was influenced by the mean horizontal length rather than size of block.