• Korean Journal of Environmental Biology
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• v.29 no.2
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• pp.98-106
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• 2011

In order to investigate water quality factors controlling chlorophyll-$a$ concentrations, the by-daily monitoring was conducted from February to November 2010 in 4 stations of Masan Bay. Seasonal variability in physico-chemical factors was mainly controlled by freshwater loading as a result of precipitation: chemical oxygen demand, suspended solids and nutrient concentrations rapidly increase during the heavy rainy season, whereas they decrease in the dry season. From late winter to mid spring, phosphorus and silica sources relative to Redfield ratio were probably functioned as limiting factor for phytoplankton flourishing in surface waters, but nitrogen concentration during mid-spring to autumn might be responsible for the increase of phytoplankton biomass. The multiple regression analysis revealed that variations in chlorophyll-$a$ concentration may be strongly correlated with changes of water temperature, chemical oxygen demand, dissolved inorganic phosphorus in spring, and salinity, chemical oxygen demand and precipitation in summer. Consequently, in the Masan Bay, a heavy rainfall event is an important factor to determine changes of biotic and abiotic factors, and in addition the dynamics of chlorophyll-$a$ concentration are strongly affected by changes of hydrological factors, especially water temperature, precipitation and nutrients.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.2
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• pp.72-79
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• 2003

This study was performed to investigate the effects of CMS (Condensed Molasses Soluble, a by-product generated from molasses during the lysine production) on the nutrient uptake, growth and yield of rice. The nitrogen uptake of rice was found to be higher in CMS treatments compared to the control treatment during the growth period. The leaf color index, height of the plants and number of tillers were increased by the application of CMS. Rice yield was highest in ($7,070kg\;ha^{-1}$) and an increase of 21% was observed in 0.3% CMS treated plots compared untreated control ($3,000kg\;ha^{-1}$). The protein content of unpolished rice increased from 4 to 28% due to the effect of CMS, while Toyo palatability score decreased. Though a decrease in pH and an increase in EC values were observed with CMS application, this phenomenon did not affect the growth and yield of rice in paddy field.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.83-83
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• 1995

The increase of population and industrial activities had brought into eutrophication in the Nakdong river. A remarkable acceleration of eutrophication brought about serious problems for water supply. Therefore, for the purpose of conservation of water quality in the Nakdong river it is necessary to control nutrients. MBOD method was use to evaluate algal growth limiting factor and algal growth potential in the Nakdong river from June to August 1994. The modified biochemical oxygen demand(MBOD) depends on the amount of available inorganic nutrient and organic substrate during 5 day incubation in the dark at 20$^{circ}C$. The MBOD assay depends on inorganic nutrients such as P and N as well as reduced carbon and called the MBOD, the MBOD-P, and the MBOD-N, respectively. The results of bioassay by MBOD(Modified BOD) method showed that the MBOD, MBOD-P and MBOD-N value were found to be in the ranges of 3.8∼96.0 mg$O_2$/l, 5.6∼94.0 mg$O_2$/l and 42.0∼220 mg$O_2$/l, respectively. And the the bioassay value was found to be the highest in Koryong area and the lowest in Waekwan area throughout the Nakdong river. The variations of MBOD-P and MBOD-N value showed similar tendencies to the variations of phosphorus and nitrogen value, respectively. By MBOD method, the relationships of MBOD, MBOD-P and MBOD-N value were MBOD ≒ MBOD-P 《 MBOD-N. The MBOD value was nearly equal to the MBOD-P value, and the MBOD-N value was 3 to 20 times more than the MBOD-P value, approximately. Therefore, in the Nakdong river, phosphorus was the limiting factor for algal growth during summer season. The algal growth potential as the concentration of chlorophyll-a in the summer was maximum 5 times more than standing crop as it.

• Journal of Korean Society of Forest Science
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• v.106 no.2
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• pp.121-129
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• 2017

The soil microbiome plays important roles in material cycling and plant growth in forest ecosystem. Although a lot of researches on forest soil fungi in Korea have been performed, the studies on forest soil bacterial communities have been limited. In this study, we conducted next generation sequencing (NGS) targeting 16S rRNA gene to investigate the soil bacterial communities from natural red pine (Pinus densiflora) forest in Mt. Janggunbong, Bonghwa-gun, Gyeongbuk, Korea. Our results showed that the entire bacterial communities in the study sites include the phyla Proteobacteria, Acidobacteria, Actinobacteria, Planctomycetes, which have been typically observed in forest soils. The composition ratio of Proteobacteria was the highest in the soil bacteria community. The results reflect that Proteobacteria is copiotroph, which generally favors relatively nutrient-rich conditions with abundant organic matter. Some rhizobia species such as Burkholderia, Bradyrhizobium, Rhizobium, which are known to contribute to soil nitrogen-fixation, exist in the study sites. As a result of correlation analysis between soil physicochemical characteristics and bacteria communities, the soil pH was significantly correlated with the soil bacteria compositions.

• Journal of the Korean GEO-environmental Society
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• v.15 no.4
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• pp.29-36
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• 2014

The purpose of this study investigates the delivery characteristics according to the load of pollutants by calculating the delivery rate of targeted areas on pollutants in Sapkyo reservoir. The main rivers of Sapkyo reservoir are Namwoncheon, Dogocheon, Sapkyocheon, Muhancheon and Gokgyocheon. The delivery rate and their characteristics of five major rivers during rainfall season are investigated. As th result, biochemical oxygen demand (BOD), total nitrogen (T-N) and total phosphorous (T-P) of total delivery rate are calculated by 0.40, 0.34 and 0.08, respectively. The delivery rate of T-P compares to other water quality is investigated relatively low. Looked at the overall characteristics of the watershed, the delivery rate of T-N and T-P is little change in the rate of the year, too. The delivery rate of T-N is calculated from 0.2 to 0.3 in the dry season, and from 0.31 to 0.39 in a flood, respectively. The delivery rate of T-P is calculated to more than 0.3 in the dry season, and 0.11 in a flood. It is similar values which the average annual delivery rate of T-P is 0.08. Therefore, the measured delivery rate of Sapkyo reservoir can be applicable such as a delivery rate of similar features of the terrain and land use.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1754-1759
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• 2002

A study was carried out to investigate the nutritive value and utilization of hybrid sorghum and perennial grass species viz. setaria (Setaria anceps) and hybrid napier when intercropped with soybean by growing Jersey crossbred heifers. Fifteen growing crossbred heifers (Jersey${\times}$Red Sindhi) of between 7-10 months age and pre-trial average body weight of 49-50 kg were divided on the basis of weight in to three treatment groups viz. $T_1$-hybrid sorghum+soybean, $T_2$-setaria+soybean and $T_3$-hybrid napier+soybean in a completely randomized block design. Intercropped forages were harvested fresh, chaffed and mixed before they were offered to the heifers. Chemical composition of the herbage, dry matter intake (DMI), body weight gain and nutrient digestibility co-efficients were estimated. The herbage mixtures had crude protein (CP) content in the range of 11.87 to 13.86% and ether extract (EE) contents were 2.91 to 3.11%, respectively. The herbage mixtures were rich in minerals (ash). The gross energy (kcal/g DM) was higher in hybrid napier+soybean, while hybrid sorghum+soybean and setaria+soybean herbage mixtures had lower value for gross energy. The hybrid sorghum+soybean and setaria+soybean herbage mixtures had higher contents of NDF, ADF, cellulose, lignin and silica as compared to that of hybrid napier+soybean herbage mixture. The heifers fed hybrid napier+soybean herbage mixture had significantly (p<0.05) higher $DMI\;g/kg\;W^{0.75}$ ($97.41{\pm}4.34$) as compared to hybrid sorghum+soybean ($88.31{\pm}2.66$) and setaria+soybean ($79.29{\pm}1.06$) herbage mixtures. Nutrients digestibility, DCP percent, DCP intake and nitrogen balance were significantly (p<0.05) higher in the heifers fed on hybrid napier+soybean herbage mixture. There was a significant (p<0.05) difference among different herbage mixtures in TDN. The heifers on setaria+soybean herbage mixture had lower average body weight gain (g/day) than those on hybrid sorghum+soybean and hybrid napier+soybean herbage mixtures. Data obtained in this experiment demonstrated that herbage mixture of hybrid napier+soybean was better than hybrid sorghum+soybean and setaria+soybean herbage mixtures in the nutrition of growing heifers. It had highest nutritive value, better digestibility co-efficients which showed better growth rate and higher feed efficiency. In ranking, hybrid napier+soybean herbage mixture was better followed by hybrid sorghum+soybean and setaria+soybean in nutritive value in the parameters studied. For future wasteland development program in humid-sub tropics of Himachal Pradesh hybrid napier and its intercropping with soybean is recommended for general adoption because of its better adaptability and higher nutritive value.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.10
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• pp.1389-1393
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• 2001

A study was carried out to investigate the nutritive value and utilization of three grass species, batiki grass (lschaemum aristatum var. indicum), guinea grass (Panicum maximum) and signal grass (Bracharia decumbens) by growing goats. Eighteen growing crossbred goats $(Anglo-Nubian{\times}Fiji\;local)$ of between 9-11 months of age and pre-trial average live weight of $9.50{\pm}1.60kg$ were divided on the basis of weight to three treatment groups in a completely randomized design. The grasses constituted the diets and they were harvested fresh and chopped into pieces before they were offered to the goats. Chemical composition of the grasses, DMI, body weight gain (BWG) and apparent nutrient digestibility coefficients were measured. The grasses had similar DM content. The CP content of the grasses was in the range of 8.3-11.2%. Crude fiber (CF) content was between 30.9-35.2%. Ether extract (EE) was low with a range of 1.2-1.8%. Nitrogen free extract (NFE) was similar (40.9%) for batiki and guinea grasses, while signal grass had more NFE content (51.1%). The grasses are good sources of minerals (ash). OM content was higher in signal grass while guinea and batiki grasses had similar OM content. The goats on signal grass had higher DMI than those on batiki and guinea grasses (p<0.05). The goats on batiki grass had lower average BWG (p<0.05) than those on guinea and signal grasses. Nutrients digestibility were significantly (p<0.05) higher in the goats on signal grass compared to those on guinea and batiki grasses. The goats on guinea grass were better (p<0.05) in the digestibility of CP, OM, NFE and ME than those on batiki grass. However, goats on batiki were significantly better (p<0.05) in digestibility of CF than those on guinea grass. Signal and guinea grasses had more DCP than batiki grass. DE was lower in batiki grass (p<0.05) than in guinea and signal grasses. There was no significant difference (p>0.05) between batiki and guinea grasses in TON. Data obtained in this experiment demonstrated that signal grass is better than guinea and signal in the nutrition of growing goats in the tropical environment of Samoa. It had the highest nutritive value, better apparent digestibility coefficients which have better growth rate and feed efficiency. In ranking, signal grass was better than guinea and batiki grasses, while guinea grass was better than batiki in nutritive value in the parameters measured. For future pasture establishment in Samoa, signal grass is recommended for consideration because of its higher nutritive value as a replacement for batiki, the most predominant grass.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.4
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• pp.530-538
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• 2016

Two experiments were conducted to determine the nutrient composition, in vitro ruminal ammonia concentrations and pH of wet distillers grains (WDG, produced from tapioca 70% and rice 30%) and to evaluate dietary effects of fermented total mixed ration (TMR) using WDG on the performance, blood metabolites and carcass characteristics of Hanwoo steers from mid fattening to slaughter. In Exp. I, average dry matter (DM), crude protein, ether extract, crude fiber, ash, neutral detergent fiber, acid detergent fiber, and nitrogen free extract of seven WDG samples from an ethanol plant with different sampling dates were 19.9%, 24.8%, 3.8%, 21.8%, 8.87%, 60.3%, 34.5%, and 40.7% (DM basis), respectively. For in vitro ammonia concentrations and pH, each sample was assigned to 7 incubation times (0, 4, 8, 12, 24, 48, and 72 h). Linear increase was observed between 12 and 48 h for ammonia concentrations, but final ammonia concentrations (72 h) were not significantly different among WDG samples and fermentation patterns of WDG samples showed similar tendency. In vitro pH varied among treatments from 0 to 24 h, but were not different statistically after 48 h. In Exp. II, 45 Hanwoo steers of 23 months ($641{\pm}123kg$) from mid fattening period to slaughter (248 days) were randomly divided into three groups of 15 pens each (five repetitions/each treatment) and assigned to one of three dietary treatments; i) Control (TMR), ii) WDG 15 (TMR containing 15% of WDG, as fed basis) and iii) WDG 28 (TMR containing 28% of WDG, as fed basis). The body weight (BW), ADG, and feed conversion ratio (FCR) of control and WDG 15 and 28 during 248 days were 760.8, 740.1, and 765.5 kg, and 0.50, 0.50, and 0.52 kg/d, and 18.6, 17.6, and 17.1, respectively. The dry matter intake (DMI) (kg/d) of control (9.11) was higher (p<0.05) than WDG treatments (WDG 15%, 8.57; 28%, 8.70). Nevertheless, DMI did not affect BW, ADG, and FCR of Hanwoo finishing steers. Blood metabolites were in normal ranges and were not different among treatments except the albumin concentration. In carcass characteristics, WDG 15 (30%) showed higher frequency of A-carcass yield grade than WDG 28 (15%) and control (7%), and WDG 28 (61%) showed higher frequency of $1^{{+}{+}}$ and $1^+$-carcass quality grade than WDG 15 (40%) and control (60%). In conclusion, using WDG up to 28% in TMR did not show any negative effect on the performance and blood metabolites, and improved carcass quality of Hanwoo steers. Therefore, WDG can be a useful feed ingredient for Hanwoo steers in mid-fattening period to slaughter.

• Ocean and Polar Research
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• v.29 no.2
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• pp.135-153
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• 2007

Temporal (seasonal) and spatial distributions and variations of various physico-chemical factors (salinity, temperature, pH, DO, COD, SPM, POC, silicate, DIP, DIN) in surface and bottom waters were studied in the coastal environment with typical macro-tidal range and monsoonal weather condition, Gyeonggi Bay, west coast of Korea. Spacial distribution patterns of these factors were generally similar to each other, and appeared to be inversely related to the distribution pattern of salinity, suggesting that water quality of the study area was primarily controlled by the physical mixing process of Han-River freshwater with nearby coastal seawater. During flooding season, silicate- and nitrogen-rich Han River water directly flowed into offshore as far as $20\sim30\;km$ from the river mouth, probably causing serious environmental problems such as eutrophication and unusual and/or noxious algal bloom, etc. Except the surface water during summer flooding season, high concentrations of nutrients appeared generally in dry season, whereas low values in spring, possibly because of the occurrence of spring phytoplankton bloom. On the other hand, nutrient flux through the estuary seems to be primarily depending on river discharge, sewage discharge and agricultural activities, especially during the rainy season. Also, nutrients in this coastal waters are considered to be supplied from the sediments of tidal-flats, which developed extensively around the Han-River mouth, especially during fall and winter of dry and low discharge seasons, possibly due to the stirring of tidal flat sediments with highly enriched pore-water nutrients by storm. And also, COD and DIN concentrations in the study area consistently increased during the last 20 years, probably because of agricultural activities and increasing discharge of industrial and domestic wastes.

• Journal of the Korea Organic Resources Recycling Association
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• v.27 no.4
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• pp.61-70
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• 2019

This study aimed to investigate the physicochemical characteristics of fish meal, bone meal, and sesame oil cake, which are readily available by-products from agriculture and fisheries, during the process of liquid fertilizer fermentation, and to examine the effects of liquid fertilizer application on seed germination and growth of tomatoes. During processing the fermentation for liquid fertilizers by using fish meal, bone meal, and sesame oil cake liquid fertilizers, the pH of the fertilizer increased in the order of bone meal > fish meal > sesame oil cake, and the concentration increased rapidly up to 30 days in all types of liquid fertilizer. The nitrogen content of the liquid fertilizers increased as fermentation progressed in the order of fish meal > bone meal > sesame oil cake. The phosphorus content increased as fermentation progressed and the highest was 1.0 % in the liquid fertilizer of sesame oil cake. The germination rate and its index of radish seeds were compared for different dilutions of each of the liquid fertilizers. Excluding the 10-fold dilution of the fish meal and oil cake liquid fertilizer, all the treatment groups showed a germination rate ≥ 95 % and the germination index tended to increase with dilution rate of liquid fertilizers. For responses of tomato growth, there were no significant differences among the liquid fertilizer treatment groups; however, the organic content, microbial density, and microbial biomass C in the soil were higher than chemical fertilizer treatment. These results demonstrated that there were differences in the characteristics of liquid fertilizers depending on the materials used, and that liquid fertilizer can be used for nutrition management for the organic crop cultivation.