• The Korean Journal of Ecology
• /
• v.20 no.1
• /
• pp.27-33
• /
• 1997

Species composition and the amount of nutrients absorbed by regenerating plants on a pine forest in the immediate postfire year were compared with those in an unburned pine forest in Kosung, Kangwon Province. Pteridium aquilinum var. latiusculum, Cyperus amuricus, Lespedeza biolor, Quercus serrata, Lysimachia clethroides were the most abundant species in burned area. In unburned area. Quercus mongolica, Rhododendron mucronulatum, Carex humilis, Rhododendron schlippenbachii, Spodiopogon sibiricus were the most abundant species. Standing biomass of understory vegetation in burned and unburned area was 170.2 g $D.W/m^2$ and 171.3g $D.W/m^2$, respectively. Nutrient concentrations of plants in burned area, especially for phosphorus and potassium, were higher than those in unburned area. The amounts of nutrients absorbed by understory plants in burned and unburned area were 37.4 and 33.6 kg/ha for N, 0.36 and 0.19 kg/ha for P, 30.6 and 18.8 kg/ha for K, 8.5 and 7.8 kg/ha Ca, 5.2 and 5.7 kg/ha for Mg, respectively. This suggests that regenerating vegetation can hold the significant amount of nutrients, although there may be considerable losses of nutrients from ecosystem after fire.

• Journal of Nutrition and Health
• /
• v.28 no.1
• /
• pp.23-32
• /
• 1995

This study was performed to investigate the influence of dietary fibers from the whole foods on the serum lipid level and bowel function in rats. The fiber sources of experimental diets were prepared by drying and milling of cereal(rice bran), vegetables(Korean cabbage, radish), fruit(apple), and sea weeds(laver, sea tangle). Each of fiber sources was mixed into the diet to make the 5% level of total dietary fiber. Male rats of Sprague-Dawley strain were blocked into 8 groups : FF, CC, CE, V1, V2, ER, S1, and S2. The animals were fed ad libitum each of experimental diets for 4 weeks. Serum triglyceride level was not significantly different among groups. The laver group showed the lowest level in the serum total cholesterol. The Korean cabbage group showed the highest level in the serum HDL cholesterol. The longest transit time was observed in the fiber free group and the shortest transit time was observed in the sea tangle group. Absorption rates of calcium were especially lower in the Korean cabbage and the sea tangle groups than the other groups. Magnesium and phosphorus absorption rates were influenced by SDF(Soluble Dietary Fiber) intake and TDF(Total Dietary Fiber) intake, respectively. Mucosa weight in the small intestine showed the tendency to increase by increasing of IDF (Insoluble Dietary Fiber) intake. especially the Korean cabbage group was the heaviest. The activity of maltase in the mucosa of small intestine was the lowest in the radish group.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.5
• /
• pp.643-650
• /
• 2009

Two metabolism trials were conducted with 24 wether lambs to investigate the effects of feeding crab meal and other protein supplements on N utilization, digestibility and Ca and P balance in sheep. The lambs (avg. BW, 25 kg) were randomly allotted to eight diets in each of two trials. The supplements were: i) none, negative control (NC); ii) soybean meal (SBM), control; iii) supplement based on industrial byproducts of both plant and animal origin (IPA); iv) experimental supplement based on byproducts of animal origin (ESA); v) hydrolyzed supplement No 4. (HESA); vi) commercial supplement based on animal protein (CS), $Pro-Lak^{(R)}$ vii) crab meal (CM); and viii) urea (U). The supplements supplied 33% of the total dietary N (CP, 9.8%; DM basis). Lambs fed the NC diet had lower (p<0.05) DM and OM digestibility. Lower (p<0.05) apparent absorption of N was recorded for the lambs fed the HESA and NC diets. Sheep fed CM had lower Ca absorption compared to SBM. Highest (p<0.05) P absorption was observed for lambs fed CS and CM and lowest for U and NC diets. Sheep fed CM had higher (p<0.05) total VFA concentration (65.7 ${\mu}mol/ml$), compared to those fed ESA, CS, and NC diets (47.3, 49.8, and 49.5 ${\mu}mol/ml$, respectively). Highest (p<0.05) ruminal $NH_3$ N (29.6 mg/dl) was observed in lambs fed the U diet, while those fed the NC diet had the lowest (p<0.05) average value (7.66 mg/dl). Lambs fed the U diet had the highest (p<0.05) blood urea N (10.67 mg/dl). The present study showed that N utilization of diets supplemented with experimental supplements based on feather meal and blood meal; commercial supplement based on animal protein, $Prolak^{(R)}$ supplement based on plant protein and blood meal; and crab meal are comparable with that of soybean meal.

• Journal of Nutrition and Health
• /
• v.32 no.3
• /
• pp.248-258
• /
• 1999

This study examined the effect of excess loading of calcium (Ca)and iron(Fe) on the bioavailability of minerals in both normal and Ca-and Fe-deficient rats. Three-week-old male rats were divided into four groups and fed experimental diets for six weeks, containing either normal (0.5%) or high(1.5%) Ca and normal (35ppm) or high (350ppm)Fe. Likewise, three-week-old male rats were first fed a Ca-and Fe-deficient diet for three weeks, and then fed one of four experimental diets for additional three weeks. In both normal and Ca-and Fe-deficient rats, ca contents of serum, liver, kidney and femur were not significantly affected by dietary Ca and Fe levels. Apparent Ca absorption(%) decreased in rats fed a high Ca diet regardless of dietary Fe levels. Magnesium(Mg) contents of serum, liver and femur significantly decreased in rats fed a high Ca diet. Fe contents of serum and liver significantly increased in rats fed a high-Fe diet, but decreased in rats fed a high Ca diet. Fe content of serum and liver significantly increased in rate fed a high-Fe diet, decreased in rats fed a high-Ca diet. Apparent Fe absorption increased in rats fed a high-Fe diet, and decreased in rats fed a high-Ca diet in Ca-and Fe-deficient rats, but dietary Ca did not seem to affect Fe absorption in normal rats. Phosphorus(P) contents of serum and femur were not significantly affected by dietary Ca and Fe levels in both normal and Ca-and Fe-deficient rats. Serum copper(Cu) decreased in rats fed a high-Fe diet, while serum zinc(Zn) decreased in rats fed a high-Ca diet in normal rats. Cu contents of liver, and Zn contents of serum and liver decreased in rats fed a high-Fe diet in Ca-and Fe-deficient rats. There results suggest that a dietary overload of Ca and Fe in both normal and Ca-and Fe-deficient rats may decrease mineral bioavailability leading to potential health problems.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.38 no.3
• /
• pp.137-142
• /
• 2005

New types of patties were prepared with surimi and crab paste, and then characterized. With an increase of additional ratios of crab paste, the moisture (64.8 to $61.5\%$) of the patties slightly decreased while the ash contents (2.3 to $3.7\%$) increased. The Hunter's color values of the patties decreased in lightness (L value, 58.79 to 54.27) but increased in redness (a value, -2.77 to 3.54). Thus, the patties that had added crab paste appeared slightly more reddish. According to the increasing of additional ratios of crab paste, sensory scores on color and flavor increased whereas the texture score decreased. From the above results, based on physical properties and sensory evaluation, the desirable additional ratio of crab paste for preparing patty was $15\%$. The calcium and phosphorus contents of the patties with the addition of $15\%$ crab paste were 148.8 mg/100 g and 139.6 mg/100 g, respectively, and their ratio (approximately 1:1) was the optimal range in body absorption efficiency. The calcium absorption rate with the $15\%$ additions was 4.9 times higher than that of the patty with no additions. Total amino acid content (16,302 mg/100 g) of the $15\%$ additions showed no difference to the patty without additions, and the major amino acids were aspartic acid, glutamic acid, leucine and lysine. Exceptionally, the cysteine content of the patty with the $15\%$ crab paste additions was 2 times higher than that found in the patty without crab paste. The major fatty acids were 16:0, 18:1n-9 and 18:2n-6 of the total lipids, and there was no difference between the patties with and without crab paste. The above results showed that crab paste can be used as a crab surimi gel source.

• 한국태양에너지학회:학술대회논문집
• /
• 2011.11a
• /
• pp.245-248
• /
• 2011

Many researches have been carried out to improve light absorption in the crystalline silicon solar cell fabrication. The rear reflection is applied to increase the path length of light, resulting in the light absorption enhancement and thus the efficiency improvement mainly due to increase in short circuit current. In this paper, we manufactured the silicon solar cell using the mono crystalline silicon wafers with $156{\times}156mm^2$, 0.5~3.0 ${\Omega}{\cdot}cm$ of resistivity and p-type. After saw damage removal, the dielectric film ($SiN_x$)on the back surface was deposited, followed by surface texturing in the KOH solution. It resulted in single-side texturing wafer. Then the dielectric film was removed in the HF solution. The silicon wafers were doped with phosphorus by $POCl_3$ with the sheet resistance 50 ${\Omega}/{\Box}$ and then the silicon nitride was deposited on the front surface by the PECVD with 80nm thickness. The electrodes were formed by screen-printing with Ag and Al paste for front and back surface, respectively. The reflectance and transmittance for the single-sided and double-sided textured wafers were compared. The double-sided textured wafer showed higher reflectance and lower transmittance at the long wavelength region, compared to single-sided. The completed crystalline silicon solar cells with different back surface texture showed the conversion efficiency of 17.4% for the single sided and 17.3% for the double sided. The efficiency improvement with single-sided textured solar cell resulted from reflectance increase on back surface and light absorption enhancement.

• Korean Journal of Soil Science and Fertilizer
• /
• v.8 no.3
• /
• pp.121-133
• /
• 1975

Soils of the agricultural land derived mostly from volcanic ash in Jeju island may be characterized by relatively high PH, high contents of organic matter and exchangeable bases, and significantly low content of available phosphorus. The PH, organic matter, and available phosphorus of the soils in northern Jeju are 6.1, 12.6%, and 23 ppm, while those of the soils in the southern Jeju are 6.4, 3.7 %, and 76 ppm respectively. Upland soils in Jeju may be classified into 4 groups on the basis of soil fertility: black soil, very dark brown soil, dark brown, and red yellow soil. The organic matter content of black soil, very dark soil and dark brown soil is 15%, 7%, and 3% respectively. The soils of high organic matter content show the high phosphorus absorption coefficient, low content of available phosphorus, and low degree of the base saturation. The soil productivity for barley in the northern Jeju is higher than that in the southern Jeju and the productivity in the western Jeju is higher than that in the eastern part. The productivity for barley is in decreasing order of dark brown soil, very dark brown soil and black soil. Yields of potato and sweet potato in Jeju are higher than in the mainland. Those crops are considered to be tolerant to aluminumtoxicity. The response of sweet potato to nitrogen, phosphorus, and potassium in Jeju soils is lower than that in the mainland, while the response of barley and rape to nitrogen and phosphorus is higher than that in the mainland. The response to fertilizer applied is greater in the northern Jeju than in the southern Jeju. Lime requirement for the Jeju soils calculated on the basis of laboratory tests is so tremendous that single application of lime required might induce adverse effect. Most of the phosphorus applied to the Jeju soils is readily fixed as unavailable form and application of phosphorus in the level of 30 to 40 kg/10a is thought to give little effect.

• Korean Journal of Soil Science and Fertilizer
• /
• v.1 no.1
• /
• pp.89-115
• /
• 1968

1. The experiment was carried out for investigating the interaction between potassium nutrition and thermoperiod (as an environment regulating factor) in relation to behaviors of several nutrients including phosphorus-32 and Potassium-42 in IPOMOEA BATAS. 2. To obtain same condition to trace the behaviors of phosphorus and potassum-42 they were simultaneously incorporated to roots. The determination of each CPM by counting twice with adequate interval and calculating true CPM of each isotope according to different half-life, was carried out with satisfactory. 3. Some specific symptoms i.e, chlorosis and withering of growing point under the condition of lower potassium level were found and was accelerated by the low night temperature. 4. A manganese shortage in growing point of the lower potassium level was found by activiation analysis and very low distribution ratio of phosphorus-32 and potassium-42 in the growing point of the lower potassium level was manifested, though the contents of nitrogen, phosphorus, potassium, sodium and magnesium were not in great difference. 5. In addition to the low water content with appearence of "hard", shorterning internode and lower ratio of roots to shoot as well as the symptoms of potassium deficiency such as brown spot in leaf blade and necrosis of leaf margin were appeared at later stage of experiment at the lower potassium level. 6. Very stimulating vegetative growth, e.g, large plant length, leaf expansion, increasing node number and fresh weight as well as high ratio of roots to shoot, high water content was resulted in the condition of higher potassium level. 7. A specific interaction between higher potassium level and thermoperiod was found, that is, the largest tuber production and the largest ratio of roots to shoot were resulted in the combined condition of higher potassium level and constant temperature while the largest plant length, fresh weight etc. i.e. the most stimulative vegetative growth was resulted in the combined condition of higher potassium level and low night temperature. 8. Comparatively low water content in the former condition of stimulative tuber production was resulted(especially at the tuber thickening stage), while high water content in the latter condition of stimulative vegetation was resulted though the higher potassium level made generally high water contents. 9. The nitrogen contents of soluble and insoluble did not make distinct difference between the lower and higher potassium level. 10. Though the phosphorus contents were not distinctly different by the potassium level, the lower potassium level made the percentage of phosphorus increased at tuber forming stage accumulating more phosphorus in roots, while the higher potassium level decreased percentage of phosphorus at that stage. 11. The higher potassium level made distinctly high potassium contents than the lower potassium level and increased contents at the tuber forming stage through both conditions. 12. The sodium contents were low in the condition of higher potassium level than the lower potassium level and decreased at tuber forming stage in both conditions, on the contary of potassium. 13. Except the noticeable deficeney of manganese in the growing point of the lower potassium level, mangense and magnesium contents in other organs did not make distinct difference according to the potassium level. 14. Generally more uptake and large absorption rate of phosphorus-32 and potassium-42 were resulted at the higher potassium level, and the most uptake, and the largest absorption rate of phosphorus and potassium-42 (especially potassium-42 at tuber forming stage) were resulted in the condition of higher potassium level and constant temperature which made the highest tuber production. 15. The higher potassium level stimulated the translocation of phoshorus-32 and potassium-42 from roots to shoots while the lower potassium level suppressed or blocked the translocation. 16. Therefore, very large distribution rate of $p^{32}$, $K^{42}$ in shoot, especially, in growing point, compared with roots was resulted in the higher potassium level. 17. The lower potassium level suppressed the translocation of phosporus-32 from roots to shoot more than that of potassium-42. 18. The uptake of potassium-42 and translocation in IPOMOEA BATATAS were more vivid than phosphorus-32. 19. A specific interaction between potassium nutrition and thermoperiod which resulted the largest tuber production etc. was discussed in relation to behaviors of minerals and potasium-42 etc. 20. Also, the specific effect of the lower and higher potassium level on the growth pattern of IPOMOEA BATATAS were discussed in relation to behaviors of minerals and isotopes. 21. An emphasize on the significance of the higher potassium level as well as the interaction with the regulating factor and problem of potassium level (gradient) for crops product ion were discussed from the point of dynamical and variable function of potassium.

• Applied Biological Chemistry
• /
• v.17 no.3
• /
• pp.193-218
• /
• 1974

These studies were carried out for the elucidation of liming effect on the growth of rice seedlings and the chemical characteristics of an acid sulphate paddy that shows not only extremely high acidity of soil but also poor growth of rice plants, consequently low yield. Thus the liming effect on the changes of acidity, oxidation-reduction potential, and the contents of iron, aluminium, sulphate, and phosphorus fractions in the soil was investigated under the waterlogging and drying condition. The reclaimable or inhibitory effect of phosphorus, iron and aluminium on the growth of rice seedlings was also investigated under liming. The results are summarized as follows: 1. After liming, the pH of the acid sulphate subsoil decreased again on drying. 2. The oxidation-reduction potential reached a minimum after 5 days of flooding and greatly decreased on liming but increased after drying. 3. The contents of ferrous iron soluble in water-and Morgan's solution reached a maximum after 15 days of flooding and only the content of water soluble ferrous iron was greatly decreased. 4. The content of aluminium soluble in water-and Morgan's solution decreased by flooding and liming, and showed a tendency to increase on drying. 5. In the limed acid sulphate soil, the content of water soluble calcium showed a highly significant negative correlation with the content of sulphate and liming decreased sulphate content in the soil. 6. The contents of total phosphorus was 496.3 ppm in the acid sulphate topsoil and 387.5 ppm in the subsoil. The content of each phosphorus fraction was in the order of Fe-P>Occ. Fe-P>Ca-P>Occ. Al-P>Al-P and Fe-P content in the soil was the highest fraction among them. 7. Lime application increased greatly Ca-P and Al-P, and Occ. Fe-P and Occ. Al-P only slightly, but decreased Fe-P differently in each soil. 8. Effect of phosphorus on the dry matter yield of rice seedlings was great. The optimum amount of phosphorus to produce maximum dry matter yield of rice seedlings appeared to be 6.8% of maximum absorption (absorption coefficient) without liming and 10.0% with liming. 9. In rice seedlings liming increased the content and uptake of calcium and silica but decreased those of iron and aluminium. Phosphorus application increased the content and uptake of phosphorus and decreased iron while the application of iron and aluminium increased their contents and uptake but decreased those of phosphorus. 10. Liming greatly alleviated such toxicity of iron and aluminium. 11. When phosphorus was applied, the dry matter yield of rice seedlings showed highly significant positive correlations with uptake of phosphorus, calcium and silica each. When iron and aluminium were applied, dry matter yields indicated significant positive correlations with the contents or uptake of calcium and silica each, but significant negative correlations with the content or uptake of iron and aluminium. 12. Under the application of phosphorus and lime, dry matter yields showed significant positive correlations with pH and Morgan's extractable calcium each of the soil samples after harvest. Under the application of lime, iron and aluminium, dry matter yields showed significant positive correlations with pH, calcium and silica each, but negative correlations with iron and aluminium contents each of the soil samples after harvest.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2005.05b
• /
• pp.1254-1258
• /
• 2005

Net outflow flux and unit load of pollutants were investigated at a paddy fields area(Soro-ri) with large-scaled plots on loam soil during irrigation seasons of $2001\~2003$. Water samples were collected, and inflow and outflow were .measured at $5\~10$ day intervals during non-storm periods and at $2\~6$ hours intervals during storm events. The average concentration of TP in percolated water was much smaller than that in irrigation and surface outflow water likely due to phosphorus absorption capacity of paddy soils. Net outflow flux in study area was significantly correlated with rainfall and surface outflow discharge. Nutrient flux from Paddy fields can be abated by reduction in outflow surface discharge.