• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.1
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• pp.57-69
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• 2001

The chemical, elemental and biochemical components of the suspended particulate matter (SPM) were investigated in order to quantify particulate organic matter (POM) and assess diet quality for suspension feeders in the southern coastal bay systems of Korea where the marine farming of the suspension feeders are most active, The intense field observation program was carried out seasonally in the three coastal bay systems of Chinhae, Gosung and Kangjin bays, The SPM was characterized as collective properties of organic carbon (POC), nitrogen (PON), phosphorus (PP) and more refined collective properties of protein (PPr), carbohydrate (PCHO) and chlorophyll a (Chl a) compound. Although the three coastal bays are regarded as phytoplankton based ecosystem, the SPM is not composed entirely with phytoplankton cells. Due to the shallow water depth, resuspension of bottom sediment contributes significantly to some of the regions. Therefore, concentration of SPM in the surface water did not co-vary with Chl a or PPr, PCHO. In general, temporal variation of POC, PON and Chl a contents in seawater were closely associated with phytoplankton biomass in the three coastal bays, However, PPr and PCHO contents in seawater were higher in Chinhae bay than in Gosung and Kangjin bays and Chl a PPr-N ratio was higher in Chinhae bay than in Kosung and Kangjin bays, since Chinhae bay is more eutrophicated than other bays. Average C : N ratios from regressions of POC and PON of SPM were 6.6, 6.6 and 5.0 in Chinhae, Gosung and Kangjin bays, respectively. SPM in Chinhae and Gosung bays appears to be made of largely phytoplankton cells and SPM in Kangjin bay appears to be contributed from the bacterial biomass due to the shallow water depth. N : P ratios from regressions of PON and PP of SPM were 10.8 and 14.7 in spring, and 18.2 and 24.6 in Chinhae and Gosung bays, respectively. With respect to the hypothetical Redfield molecule, phytoplankton appears to be limited by the lack of N and f in spring and summer, respectively, in the two bays, In Kangjin bay, N : P ratios from regressions of PON and PP of SPM were varied from 6.3 to 12.8 throughout the year. The low N : P ratio with resepct to the hypothetical Redfield molecule, phytoplankton growth appears to be limited by the lack of N-nutrients.

• Journal of Wetlands Research
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• v.17 no.3
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• pp.228-236
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• 2015

Urbanization causes many environmental, hydrological and ecological problems such as distortion of the natural water circulation system, increase in nonpoint source pollutants in stormwater runoff, degradation of surface water quality, and damage to the ecosystem. Due to the increase in impervious surface by urbanization, developed countries apply low impact development (LID) techniques as important alternatives to reduce the impacts of urbanization. In Korea, LID techniques were employed since 2012 in order to manage nonpoint source pollutants. LID technology is a technique for removing pollutants using a variety of physical, chemical and biological mechanisms in plants, microorganisms and filter media with the reduced effluence of stormwater runoff by mimicking natural water circulation system. These LID facilities are used in a variety of filter media, but an assessment has not been carried out for the comprehensive comparison evaluation of adsorption and desorption characteristics for the pollutant removal capacity. Therefore, this study was conducted to analyze the adsorption and desorption characteristics of various filter media used in the LID facilities such as sand, gravel, bioceramic, wood chips and bottom ash etc. in reducing heavy metals(Pb, Cu). In this study, the adsorption affinity for Pb in all filter media was higher than Cu. Pseudo second order equation and Langmuir-3 isotherm are more applicable in the adsorption kinetic model and adsorption isotherm model, respectively. As a result of the desorption experiment, the filter media does not exceed KSLT which is the hazardous substance leaching limit, showing the capability of the filter media in LID. The bioceramic and woodchip as filter medias were evaluated and exhibited excellent adsorption capacity for Pb.

• Journal of Animal Environmental Science
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• v.15 no.3
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• pp.217-224
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• 2009

The pig slurry is one of important fertilizer source for production of crops in recent years, but it has many controversial points of utilization such as offensive odor, lack of spread equipment and farmland possession, respectively. This study was carried out in order to remove water pollutants and malodor of pig slurry using biofiltration system. The biofiltration system consists of pig slurry separator, mixing shift and attached blade for sawdust or ricehull, air injection nozzle and outlet for pig slurry and sawdust or ricehull. The characteristics pH, $BOD_5$ (Biochemical Oxygen Demand), $COD_{Mn}$ (Chemical Oxygen Demand), SS (Suspended Solid), T-N (Total Nitrogen), T-P (Total Phosphorus) of the untreated pig slurry used in this study were 7.2, 34,450, 24,604, 71,000, 4,194, $1,631\;ml/{\ell}$, respectively. The $NH_3$ (Ammonia) and $H_2S$(Hydrogen Sulfide) concentration were 70.0, 9.6 ppm, respectively. The initial total microorganisms of pig slurry were $5.0{\times}10^3\;cfu/ml$, and Salmonella, Bacillus were $5.8{\times}10^2$, $1.1{\times}10^3\;cfu/ml$, respectively. The filtration system was very effective on removal of water pollutants of pig slurry. The removal efficiency of the offensive odor of ammonia and hydrogen sulfide in sawdust was higher than those of ricehull. The total microorganisms and bacillus of pig slurry are on the increase by sawdust and ricehull, but Salmonella showed a tendency to decrease in number after that time. Accordingly, the filtration system was very effective to produce a good quality pig slurry.

• Korean Journal of Environmental Agriculture
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• v.16 no.3
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• pp.259-263
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• 1997

To investigate chemical changes of agricultural water in Nam river used for the basic information. Samples were collected from seven sites along the Nam river and were analyzed for inorganic content from April to September in $1994{\sim}1995$. Average value of analyzed inorganic concentrations at seven sampling sites were pH 7.9, COD 7.3mg/l, $NO_3-N$ 1.2mg/l, $Na^+$ 6.2mg/l, $Cl^-$ 14.8mg/l, EC 0.13dS/m, $PO_4\;^{3-}$ 0.21mg/l, $K^+$ 2.6mg/l, $Ca^{2+}$ 10.8mg/l,$Mg^{2+}$ 2.9mg/l, $SO_4\;^{2-}$ 10.5mg/l, $Fe^{3+}$ and $Zn^{2+}$ 0.02mg/l. The monthly average value of COD, $NO_3-N$, $Na^+$ and $Cl^-$ showed highest peak in July $8.4{\sim}11.6$, $1.1{\sim}1.7$, $5.4{\sim}13.1$ $18.9{\sim}27.9mg/l$. The highest region of average COD, $NO_3-N$, $Na^+$ and $Cl^-$ were Weola pumping station, $8.8{\sim}11.3$, $1.6{\sim}2.4$, $9.0{\sim}10.2$ and $21.7{\sim}23.0mg/l.$ The ionic $copmposition({\Sigma}A/{\Sigma}C)$ : ratio between total equivalant of anions and canon) of Nam river was higher at Weola pumping station than other topography. The EC was positively correlated with $K^+$, $Ca^{2+}$, $Mg^{2+}$, $Na^+$, $Cl^-$ and $SO_4\;^{2-}$.

• Korean Journal of Agricultural Science
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• v.36 no.1
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• pp.63-71
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• 2009

Two experiments were conducted to investigate feed value of Yukmijihwangtang (herbal medicine) meal. In experiment 1, the chemical composition of Yukmijihwangtang ingredients was determined before and after extraction, and investigated the effects of partial substitution of dried Yukmijihwangtang meal on TMR for fattening cattle. In experiment 2, nine Korean native male goats were employed to investigate the palatability and ruminal parameters of Yukmijihwangtang meal silages. In experiment 1, the crude protein content after water extraction was higher in Alisma orientale Juzepczuk (Teaksa), and lower in Pachyma hoelen Rumph (Bokryeong). the crude fat content after water extraction was higher in Cornus officinalis Sieb. et Zucc (Sansuyu), and lower in other ingredients. ADF content after water extraction of Cornus officinalis Sieb. et Zucc (Sansuyu) was higher compared to those of Pachyma hoelen Rumph (Bokryeong) and Paeonia suffruticosa Andrews (Mokdanpi). Dioscorea japonica Thunberg (Sanyak) was the lowest in ADF content. Dry matter disappearance was increased by adding Yukmijihwangtang meal to TMR. In experiment 2, feed intakes of Yukmijihwangtang silage containing molasses (0.5 and 1%) for 30 min and 6 hr were significantly higher than that of control (0%) in Korean native goats. In various ruminl parameters, molasses addition to silage materials trended to increase total VFA, propionate and valerate contents, but trended to decrease iso-butylate, butylate and iso-valerate contents in Korean native goats. In conclusion, Yukmijihwangtang meal could be used as partial substitution of low level in TMR for fattening cattle. Molasses supplementation to silage materials contained with herbal medicine meal could improve its nutritional quality and palatability for Korean native goats. One percent level of molasses addition could give a useful effect in ensiling.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.1
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• pp.75-82
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• 2010

Indoor cultivation plots for watermelon plant mostly have salt-accumulation problem because of continuous cropping especially with the heavy applications of chemical fertilizers. Thus, this study was conducted to investigate selected soil properties and watermelon growth condition as affected by the application of different farming practices in the salt-affected soils of greenhouse plots used for continuous watermelon production. Five different practice conditions in the experimental plots were applied, 1) a conventional farming practice (CFP), 2) a nitrogen-phosphorus-potassium (NPK) fertilizer management practice (FMP), and 3) the FMP with different amounts (5, 10, and 15 ton $ha^{-1}$)of fresh rice straw treatments (FMP-RS), for three years of study. As comparing with CFP plots, soil organic matter content gradually increased during the experimental years, whereas it decreased in the FMP only plot. Soil pH was not changed in the CFP and FMP plot, but it declined in the FMP-RS plots; however, it increased again from the third year in the FMP-RS plots with applying 10 and 15 ton $ha^{-1}$ of RS treatments. The concentrations of exchangeable cations, $Ca^{2+}$ and $Mg^{2+}$, except $K^+$, and water-soluble anions, ${NO_3}^-$, $Cl^-$, ${SO_4}^{2-}$ and ${PO_4}^{3-}$, markedly decreased in FMP and FMP-RS plots. In particular, the application of rice straw tended to significantly decrease the ion concentrations, especially most anions, in the first year, but there was no more decrease in the second and third study years. With relation to the ion concentrations, the changes of electrical conductivity (EC) after applying the management practices showed very similar to those of the ion concentrations. In addition, incidence of withered watermelon plant after applying the management practices dramatically declined from approximately 20% in the CFP plot to 3.5% in the FMP-RS plots. Water melon fruit weight was also improved by the management practices, especially FMP-RS. Therefore, the fertilizer and/or fresh rice straw application management practices are beneficial to improve salt-affected soils and watermelon plant growth condition.

• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.3
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• pp.13-22
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• 2022

In order to improve water quality of the water system contaminated with dyes, biochars prepared using discarded waste resources were applied in this study. Biochars with a large specific surface area were manufactured using street tree pruning products or waste wood, and were applied to remove an organic dye in synthetic water. Biochars were made by pyrolysis of typical street tree porch products (Platanas, Ginkgo, Aak) and waste wood under air-controlled conditions. Methylene blue (MB), which is widely used in phosphofibers, paper, leather, and cotton media, was selected in this study. The adsorption capacity of Platanas for MB was the highest and the q_max value obtained using the Langmuir model equation was 78.47 mg/g. In addition, the adsorption energy (E) (kJ/mol) of MB using the Dubinin-Radushkevich (D-R) model equation was 4.891 kJ/mol which was less than 8 kJ/mol (a criteria distinguishing physical adsorption from chemical adsorption). This result suggests a physical adsorption with weak interactions such as van der Waals force between the biochar and MB. In addition, the physical adsorption may resulted from that Platanas-based biohar has the largest specific surface area and pore volume. The ∆G value obtained through the adsorption experiment according to temperature variation was -3.67 to -7.68, which also suggests a physical adsorption. Considering these adsorption results, the adsorption of MB onto Platanas-based biochar seems to occur through physical adsorption. Overall, it was possible to suggest that adsorption capacity of the biochr prepared from this study was equal to or greater than that of commercial activated carbon reported in other studies.

• Korean Journal of Ecology and Environment
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• v.55 no.1
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• pp.60-75
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• 2022

The Bayesian algorithm model is a model algorithm that calculates probabilities based on input data and is mainly used for complex disasters, water quality management, the ecological structure between living things or living-non-living factors. In this study, we analyzed the main factors affected Korean Estuary Trophic Diatom Index (KETDI) change based on the Bayesian network analysis using the diatom community and physicochemical factors in the domestic estuarine aquatic ecosystem. For Bayesian analysis, estuarine diatom habitat data and estuarine aquatic diatom health (2008~2019) data were used. Data were classified into habitat, physical, chemical, and biological factors. Each data was input to the Bayesian network model (GeNIE model) and performed estuary aquatic network analysis along with the nationwide and each coast. From 2008 to 2019, a total of 625 taxa of diatoms were identified, consisting of 2 orders, 5 suborders, 18 families, 141 genera, 595 species, 29 varieties, and 1 species. Nitzschia inconspicua had the highest cumulative cell density, followed by Nitzschia palea, Pseudostaurosira elliptica and Achnanthidium minutissimum. As a result of analyzing the ecological network of diatom health assessment in the estuary ecosystem using the Bayesian network model, the biological factor was the most sensitive factor influencing the health assessment score was. In contrast, the habitat and physicochemical factors had relatively low sensitivity. The most sensitive taxa of diatoms to the assessment of estuarine aquatic health were Nitzschia inconspicua, N. fonticola, Achnanthes convergens, and Pseudostaurosira elliptica. In addition, the ratio of industrial area and cattle shed near the habitat was sensitively linked to the health assessment. The major taxa sensitive to diatom health evaluation differed according to coast. Bayesian network analysis was useful to identify major variables including diatom taxa affecting aquatic health even in complex ecological structures such as estuary ecosystems. In addition, it is possible to identify the restoration target accurately when restoring the consequently damaged estuary aquatic ecosystem.

• Food Science of Animal Resources
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• v.25 no.4
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• pp.391-396
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• 2005

The objective of this study was carried out investigate the changes of carcass characteristics, physico-chemical characteristics and fatty acid composition in crossbred pigs (Korean native breed ${\times}$ Landrace breed) by backfat thickness. A total 182 Pigs were divided into 3 groups by there backfat thickness, i.e., <11.80mm, $11.80\~25.01mm\;and\;25.01mm<.$ The live weight carcass weight and dressing percent of backfat thickness 25.01mm< group were higher compared to those for backfat thickness <11,80mm and $11.80\~25.01mm group, but the final grade were lower. The pH of backfat thickness 25.01mm< group were higher compared to those for backfat thickness <11.80mm and $11.80\~25.01mm$ group. Shear lone of 25.01 mm< group were lower than that of other groups. Water, crude fat content and cooking loss have no difference between the 3 groups. The hardness of backfat thickness 25.01mm< group were higher compared to those for backfat thickness <11.80mm and $11.80\~25.01mm$ group. The yellowness $(b^*)$ of meat and fat color in backfat thickness 25.01mm< group were lower compared to those for backfat thickness <11.80mm and $11.80\~25.01mm$ group. The stearic acid and saturated fatty acid content were higher compared to those for backfat thickness <11.80mm and $11.80\~25.01mm$ group but the linoleic acid and unsaturated fatty acid content were lower.

• Journal of Animal Science and Technology
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• v.44 no.6
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• pp.769-782
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• 2002

Three kinds of green forages(rye, oats and mixed forages) was harvested and mixed with rice straw, wheat bran and 2 grains(corn and soybean), which harvested 2 different dates(common harvesting dates, 7 days early to common harvesting dates). And each mixture was ensiled in 6 poly vinyl chlorides that was 60 liter, immediately. They were opened at 0, 5, 10, 25, 35, 60 and 100 days after ensiling for chemical analysis. And its effects of those TMFFs on feed values were observed. Average contents of water, crude protein, ADF, NDF, Ca and P of formulated TMFs were 72 to 75%, 14.75 to 18.24, 12.47 to 19.07, 39.82 to 47.01, 0.99 to 1.07 and 0.38 to respectively. Crude protein content was the highest in the mixed forages-TMFF and the lowest in the rye-TMFF. The ADF and NDF contents of rye-TMFF were higher than orthers. And CP, ADF, NDF, TDN, P and Ca contents were no significant difference among treatments regardless of storage period and harvest time, but all treatments indicated good quality. Intenal temperatures of TMFF were shown to be 1 to 5$^{\circ}C$ higher than ambient temperatures. The temperature of the Oat-TMFF formulated during winter sustained higher to the level of 6${\sim}$9$^{\circ}C$ for 10 days. The pH of TMFF were 4.0 to 4.2 and the content of $NH_3$-N was shown to be 7.79 to 8.23mg/$d{\ell}$. In the VFA contents, any tendency was not shown at all treatments depending on harvest time. Even though rye-TMFF showed the lowest VFA value. At all treatments except rye-TMFF, propionate production was increased and stable after 25 days of storage. Digestibility of rice straw from TMFF on DM basis was 15${\sim}$20% higher compared with non-treated rice straw.