• The Korean Journal of Ecology
• /
• 제23권2호
• /
• pp.169-173
• /
• 2000

Seasonal distribution of ectomycorrhizal associations in various types of forest in a boreal forest in Manitoba. Canada was investigated. Alsohe relationship between ectomycorrhizal growth and pine pollen nutrients was examined. In four different forest stands, ectomycorrhizas tended to be lower in the spring than in the summer and fall samples. In addition. a mature jack pine (Pinus banksiana) stand showed higher mycorrhizal activities than a young jack pine stand. Growth of Suillus brevipes hyphae wa ts stimulated by additions of pollen representing mean pollen deposition in Mistik Creek study area after 30 and 70 days of growth with dextrose availability. This result suggests that the peak ectomycorrhizal activity is followed by pollen deposition in the study region and therefore, addition of pine and spruce pollen in early or middle of June in the boreal forest can be an important seasonal nutrient source for ectomycorrhizal growth.

• Membrane and Water Treatment
• /
• 제10권1호
• /
• pp.83-89
• /
• 2019

The most common way of reducing non-point source pollutants from agricultural areas is the installation of reservoirs. However, this method is only effective for surface runoff of settleable pollutants. This study was conducted to estimate the effect of interflow, baseflow, and surface runoff on pollutant runoff in a small agricultural catchment. Runoff of organic matters, SS, and T-P were directly proportional to the rainfall variation, while ammonia and nitrate were inversely proportional to the amount of rainfall. The interflow and baseflow was only 46% of the total stream flow, but the nitrate load reached 78%. The interflow as a nutrient transport pathway should be considered for managing a stream water quality. It requires careful attention and appropriate control methodology such as vegetation to consider the influence by interflow. The reservoir as a dry extended detention pond (DEDP) has function of nutrient captor.

• Journal of Microbiology and Biotechnology
• /
• 제10권2호
• /
• pp.201-207
• /
• 2000

The freshwater green alga Chlorococcum sp. grew on NH_4^{+},{\;}NO_3^{-}$, urea, yeast extract, and peptone as the nitrogen source showing similar pattens of growth and secondary carotenoid (SC) production. However, the most suitable nitrogen source for the induction fo SC was urea. The dffects of nutrient levels (urea, phosphate, sulfate, ferrous iron, and salt) on growth and SC production were stydied by varying the concentration of each nutrient in batch cultures. High biomass production was achieved in cultures containing 20-28 mM urea, 4.8-10 mM phosphate, 1.6 mM sulfate, 70 mM phosphate, 1.6 mM sulfate, 170 mM NACl, and $50{\;}\mu\textrm{M}$ iron. The optimum concentrations of nutrients for biomass and for the SC accumulation in biomass were evaluated and the two media for achieving high biomass production and SC production were thus developed. The extent to which each parameter to stimulate the formation of SC in the alga were varied and the potentially improned SC prodution by manipulating the nutrient levels in the modified media were descussed.

• Journal of Community Nutrition
• /
• 제8권1호
• /
• pp.3-8
• /
• 2006

This retrospective study was designed to evaluate the nutrient contributions of the five meal components of school lunch menus planned for elementary students in two school districts (District A and B) in the Midwestern state of the United States. The 4-week cycle menu was planned for two time periods (Period 1 and Period 2) following guidelines for NuMenus and general menu planning principles. Menu components of planned and served menus for two time periods were analyzed using $Nutri-Kids^{TM}$. No significant differences in the nutrient content of between Periods 1 and 2 were found for District A. District B served significantly more vitamin A and total fat in Period 1 and significantly more calories, iron, vitamin A, protein, and total fat in Period 2 than was planned. The major nutrients provided by the entree component included protein, calories, cholesterol, total fat, saturated fat, and sodium. Milk was an important source of calcium and provided approximately one-third of the total protein and vitamin A in the meal. The vegetable/fruit component was the major source of vitamins A and C. The grain/bread component provided approximately 20% of the carbohydrates among five meal components. The miscellaneous component affected the sodium and fat content of the menus. Menu planners can use the results of this study to enhance their knowledge of the nutrient contributions of each meal component and as inputs for planning menus that meet children's nutritional requirements.

• Asian-Australasian Journal of Animal Sciences
• /
• 제19권1호
• /
• pp.55-60
• /
• 2006

This experiment was conducted to investigate the effects of selenium (Se) sources and levels on growth performance, nutrient digestibility and Se retention in growing-finishing pigs. A total of 56 crossbred pigs ([$Landrace{\times}Yorkshire$]${\times}$Large White) with average $28.5{\pm}0.2kg$ BW were allotted to 7 treatments on the basis of sex and weight in two replicates and four pigs per pen. A $2{\times}3$ factorial arrangement of treatments was used in a randomized complete block (RCB) design. Two sources of Se (selenite Se or Se-enriched yeast) were added at 0.1, 0.3 and 0.5 mg/kg to each treatment diet. A basal diet without Se supplementation was the seventh treatment group. Three pigs per treatment were randomly selected and samples of loin, liver, pancreas and a kidney were collected, frozen and later analyzed for Se. The digestibility trial was conducted to evaluate the apparent absorption and retention of Se and availability of other nutrients. Growth performance was not affected by dietary sources and levels of Se. No growth retardation was observed in the 0.5 mg/kg dietary Se treatment group regardless of Se sources. The Se concentration of serum in Se supplemented groups was increased compared with the control group (p<0.01). During the growing and finishing phase, Se in serum was clearly increased when organic Se was provided (p<0.01). Interaction of Se source ${\times}$ Se level was observed in Se concentration of loin, liver and pancreas of the pigs at the end of experiment. Selenium retention in the liver, kidney, pancreas and loin of pigs was increased as dietary Se level increased and was higher when pigs were fed organic Se resulting in an interaction response (p<0.01). Nutrient digestibilities were not affected by dietary Se sources or levels. No dietary Se source ${\times}$ Se level interaction was observed in nutrient digestibility. The results from this experiment indicated that dietary Se sources and levels affected the distribution of Se in the body of growing-finishing pigs. Organic source of Se, such as Se-enriched yeast resulted in higher serum and tissue Se concentration compared to inorganic form, while no beneficial effects on nutrient digestibility were observed from dietary Se supplementation in growing-finishing pigs.

• Journal of Nutrition and Health
• /
• 제33권7호
• /
• pp.763-773
• /
• 2000

On the basis of the concept retained in nutition label(NL) the consumer's perception use and demand on NL nutrition knowledge(NH) purchase of nutrient controlled food and dietary modification for health were examined. The subjects were 1203 house wives mainly in the age of 30-40 and self administered questionnaire was employed. The results were as follows. Subjects' demand on nutrition information was greater while the availablity and usefulness of NL was unsatisfactory. The purchase frequencies of nutrient controlled foods were higher compared to NL reading. The use comprehenison reliability of nutrition information were better in high NK group compared to low NK group except the reliability on health claims. The required nutrients for content information were in the order of calorie Ca cholesterol Fe protein and total fat. The demand for nutrient content information was carrelated with intention of subjects' dietary modification but not the use of NL. These results indicate that NL be a good source of nutrition information and the consumers' demand for NL was based on their dietary purpose though the use of NL was unconfirmed.

• Journal of Nutrition and Health
• /
• 제23권4호
• /
• pp.287-297
• /
• 1990

The status of the nutrient supplement usage of the adults in Seoul was investigated. One thousand two hundred adults from various age groups were chosen as the subject of this study. Data of this study were obtained by means of self administered questionnaire for demog-raphic characteristics(sex,age,edcation,income,occupation) and behavioral characteristics (reason for using nutrient supplement or not using,exercise,drinking & smoking). The overall response rate was 85%(n=1031). As a result, a substantial percentage(40%) of the subjects were used some kinds of nutrient supplement. The higher the age, educational level, and family income were, the higher the percentage of nutrient supplement usage was. But there was not the significant difference between sexes(38% in men vs 34% in women). And supple-ment usage was higher in the thin and obese groups than the average weight groups. Majority of subjects indicated that the information source of supplement was "Family/Friends" or "Phy-sician/Pharmacist". KEY WORDS: supplement usage vitamin/mineral supplement health food.

• Environmental Engineering Research
• /
• 제15권1호
• /
• pp.41-48
• /
• 2010

This paper describes the influence of nutrient salts eluted from the bottom of a closed water area where polluted sediment has been deposited by inflowing river water. The elution pattern was monitored at our experimental facility. Both the sediment pore water and water above the bottom were sampled using a dialyzer sampler (peeper). The pore water of the eutrophicated sediment contained a large amount of nutrient salts, and the effect of elution was confined to a limited area of the bottom surface. The nutrient concentration of the sediment pore water was closely related to both the water temperature and dissolved oxygen (DO) concentration. The eluted nutrients from the sediment provided a source for phytoplankton and algae growth. This experimental data indicated that the water quality of the surface was not directly connected to the eluted nutrient salts, while it was indirectly affected by the total ecosystem, including all the organisms within an area and their environment.

• 상하수도학회지
• /
• 제26권6호
• /
• pp.833-840
• /
• 2012

This study aimed to investigate growth rate and nutrient removal efficiency of Chlorella vulgaris according to nitrogen sources and frequency of pH adjustment. Nitrogen and phosphorus removal efficiencies were evaluated in the three different conditions using $NO_3{^-}$, $NH_4{^+}$ as a sole nitrogen source and mixed condition. Initial nutrient concentrations in artificial wastewater were 30 mg-N/L and 3 mg-P/L similar to secondary wastewater effluent. When nitrogen source was $NO_3{^-}$, there was no inhibition on the growth of C. vulgaris with adjusting pH every 24 hr while growth inhibition occurred with $NH_4{^+}$ caused by pH drop. N, P removal efficiencies were no significant depending on the nitrogen sources. As pH was adjusted to 7 by pH-stat, growth rate and nutrient removal efficiencies were increased compared to adjusting pH every 24 hr, however, growth rate and nutrient removal efficiencies were no significant depending on the nitrogen sources.

• 농업과학연구
• /
• 제44권2호
• /
• pp.235-243
• /
• 2017

A total of 112 crossbred pigs [(Yorkshire ${\times}$ Landrace) ${\times}$ Duroc] with an average body weight (BW) of $27.98{\pm}1.28kg$ were used to evaluate the effects of replacing soybean meal (SBM) with rapeseed meal (RSM) as a source of protein on growth performance, nutrient digestibility, blood characteristics, and fecal noxious gas emission in growing pigs. The pigs were blocked and stratified based on BW into one of four dietary treatments in a 6-week trial. Each treatment consisted of 7 replicate pens with 4 pigs per pen (2 barrows and 2 gilts). Treatments were 1) maize-SBM based diet, 2) diet containing 2% RSM, 3) diet containing 4% RSM, and 4) diet containing 6% RSM. Supplementation with RSM resulted in no differences in growth performance, nutrient digestibility, and noxious gas emission, as compared with SBM supplementation during the experimental period (p > 0.05). Pigs fed with increased dietary RSM (0, 2, 4, and 6% of feed) had linear decreases in average daily gain (ADG) (p = 0.010) and nitrogen digestibility (p = 0.036) and a linear increase in blood creatinine concentration. In conclusion, RSM fed pigs had no detrimental effects on their growth performance, nutrient digestibility, blood characteristics, and fecal noxious gas emissions, as compared with SBM fed pigs. Thus, RSM is a good alternative to SBM as a protein source in growing pigs' diets.