• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.416-431
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• 2000

The objective of this study was to determine the effects of various kinds of composts on the change of soil chemical properties in upland soils. Field experiments were conducted in the loam and sandy loam soils. Various kinds of composts such as poultry manure compost(PMC), cow manure compost(CMC), human excrement sludge(HES), and food industrial sludge compost(FISC) were applied annually at rates of 0, 40, and $80Mg\;ha^{-1}$ to soils grown with soybean and maize plants for 4 years during 1994 to 1997. The results of this study were as follows : The continuous application of human excrement sludge decreased soil pH up to 4.4~5.0, while other compost treatments increased soil pH compared with control plot. The EC increased initially and showed their maximum values at 20days after compost application, and then decreased up to 40 days, thereafter kept a certain level. The available phosphorous accumulated at 0~20cm depth in loam soil, and 0~50cm in sandy loam soil. Annual accumulation rates were 17% higher in sandy loam soil than loam soil. The more compost application rates and times, the higher base saturation percentage increased in upland soils. Four year's application at a rate of $80Mg\;ha^{-1}$ per year increased the base saturation percentage to 87~97% compared with 45% at control plot in the loam soil. While in sandy loam soil only three year's application of same rate increased the base saturation percentage to 81~92% compared with 30.4% at control plot. The average annual increasing rate of base saturation percentage at the same application rates of composts were higher in sandy loam soil by 2.0~3.7 times than in loam soil. The application of compost increased the exchangeable Ca, Mg, and K contents of soils by 2, 2~3, and 3~5 times, respectively, compared with the control. The contents of exchangeable cations were high in surface soil, and decreased with increase of soil depths. In the case of heavy metal content, there were no difference at the application of PMC and CMC but Ni, Fe, Zn, Cu was increased a little when the HES applied, and Ni and Cr was increased application with FISC.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.6
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• pp.301-306
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• 2005

Asian dust was collected in Korea and soils in the arid area of northern China were analysed for its physical and chemical properties, and mineral compositions for in order to interpret the origin of Aeolian soils and estimate the effect of dust wind on the soil environment in Korea. Asian dust was collected at Suwon in Korea from 2002 to 2004. Soil samples were collected from the desert and Loess plateaus around Gobi desert in China. As a result of analysis of desert soil distributed on northern region and Loess soils in China, it was observed that soil pH was about 9, organic matter 11 to $23g\;kg^{-1}$, and CEC 7.1 to $18.4cmolc\;kg^{-1}$, showing a high spatial variation among different sampling locations. About 62 to 80% of particles were composed of quartz and feldspars, 2 to 14% calcite ($CaCO_3$) and dolomite [$Ca{\cdot}Mg(CO_3)_2$], and trace other clay minerals. All the dust particles in Korea were below 50 m in diameter, and the mineral compositions were quartz, mica, feldspar and some clay minerals. Major components of clay mineral of Asian dust was mainly illite as compared to the kaolin of soils in Korea. The base saturation of exchangeable Ca, Mg, K and Na in the Asian dust was above 250% due to the high content calcite. Most of upland soil in Suwon was thin and sharp type, but Asian dust in Korea was the spherical shape. Asian dusts in Suwon, Korea, did not show a definite mineralogical variation of the dust during the collection period. Difference between the Asian dust collected in Korea and the soils in arid area of China was observed in the physical and chemical properties, especially for particle size distribution, cations such as Ca, Mg, K and Na. However, some similarities were found on the mineral compositions and chemical properties between Asian dust collected in Korea and the loess of China.

• Journal of Animal Science and Technology
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• v.48 no.2
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• pp.293-306
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• 2006

We characterized physicochemical properties and examined the organoleptic and textural evaluations of Feta cheese made from goat's milk. Nutritional compositions of goat Feta cheese were fat 23.50%, protein 11.03% with moisture content of 59.54%. Cell numbers of lactic starter cultures in Feta cheese maintained from log 8.46 CFU/g and pH 5.76 during storage at 4℃ for 14 day's aging. The color of Feta cheese was whitish (L. 93.19) at after finishing brine salting, but became a little yellowish(b. 3.52) (a. -0.71). For texture profile analysis of goat Feta cheese, hardness, fracturability springness, and cohesiveness seemed to be week, but adhesiveness gumminess, chewiness, and resilience were enhanced as aging times extended to 14days, resulted in the overall textural properties was to be superior to control cheese(commercial Mozzarella cheese). Organoleptic evaluations were examined based on the intensities and the preferences for flavour, tastes, texture and mouth feeling. saltiness, bitterness and acidity were stronger in the intensities than control cheese, but the preferences were enhanced by aging to be better than control cheese at 14 days and later on, however, the texture changed to be weaker in hardness and unpleasant in mouthfeel. The fatty acid compositions of Feta cheese analysed by Gas chromatography were saturated fatty acid 42.06%, monoenoic acids 29.67%, di-enoic acids 24.24%, tri-enoic acids 1.21%.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.109-116
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• 2002

The objective of this study was to know the qualities of soil and shallow groundwater in plastic film house fields around Central Part of Korea. The study was conducted at 11 sites in Suweon, Hwasung, Pyungtaek, Yongin and Chuncheon through May to August in 1999. Soil textures of plastic films house were mainly sandy loam or loam. Electric conductivity and organic matter content of surface soils mostly exceeded the critical levels for crop production. Average concentration of $NO_3-N$ in the sha]low groundwater was 19.1 mg/L, and it reached almost the limiting level of agricultural groundwater quality (20 mg/L). Moreover about 36% of survey sites exceeded the limiting level of agricultural groundwater quality. Sulfate concentrations also at some sites exceeded agricultural groundwater quality limit level (50 mg/L). Nitrate-N, one of the most important factors in the groundwater quality, had positive correlations with other ions in foundwater.

• Korean Journal of Environmental Agriculture
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• v.5 no.1
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• pp.1-10
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• 1986

To investigate the effects of paper sludge on the seasonal variations of soil humus, paper sludges were applied to the pots at the rates of 600㎏/10a which was either preadjusted C/N ratio to 30 : 1 or not adjusted. The effects were compared with those of control. 1) The contents of ether soluble materials, resins, water soluble polysaccharides, hemicellulose, cellulose, ligno-protein, humic acid and fulvic acid were higher in the sludge treated soil than in the control, furthermore, the content of ligno-protein had positive correlation with that of organic nitrogen in soil. 2) Optical density of UV and visible spectra of humic acid obtained from all the treated soil was decreased with increasing wavelength. In functional groups of humic acid, phenolic-OH/alcoholic-OH ratio was slightly higher in the sludge treated soil than in the control. The types of humic acid in all treated soil were P and Rp types. 3) The infrared spectra of humic acid extracted from the soil were characterized by main absorption bands in the regions of $3, 400cm^{-1}$(H-bonded OH), $2,900cm^{-1}$ (aliphatic C-H stretching), $1,630cm^{-1}$ (aromatic C=C and/or H-bonded C=O) and $1,050cm^{-1}$ (Si-O of silicate impurity).

• Korean Journal of Environmental Agriculture
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• v.17 no.2
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• pp.174-181
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• 1998

In four citrus grow of Satsuma mandarin (rootstock of trifoliate orange) including two grove of organical management and two groves of conventional management, spores of arbuscular mycorrhizal(AM) fungi were identified and seasonal changes in spore density in soils and AM colonization of citrus roots were investigated. AM colonization in weeds found in the groves were also examined. Three species of Glomus (G.deserticola, G. vesiculiferum, G. rubiforme ) and one unknown species of Acaulospora were observed in all of the groves. Annual mean density of AM fungal spores were in the range of 10,000${\sim}$40,000 per 100g soil with more spores in the organically-managed groves. The least spores were observed in December in all groves, and the most spores in April in the organically-managed groves while in February or April in the conventionally- managed. Annual mean AM colonization more 27% of citrus root were observed in the organically-managed with the high peaks in April and October and the minimum in August, while mean colonization less than 15% in the conventionally-managed with the peak in February and the minimum in different times depending on groves and years. AM colonization corresponded to a sigmoidal curve consisting of a laf phase during winter and a subsequent increase in spring, then succeeded by a maximum, and then a decrease at the end of vegetation. Fungal spore density and AM colonization showed a parallel pattern during the sample period. The seasonality appeared to be related more to the phenology of the plant than to the soil factors. Generally more spore density and AM colonization were found in organically managed groves. AM colonization was not correlated with available P and organic matter content in soil in this field investigation. Among sixteen weed species found in the groves, Astrogalus sinicus of Leguminosae, Portulaca oleracea of Portulacaceae showed high colonization in all groves and they can be considered as a source of inoculumn and host plants for propagation of AM fungi.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.749-758
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• 2019

The aim of this study is to provide a scientific basis for decision making regarding environmental damage in case of future chemical accidents by evaluating the ecotoxicity of 4 substances requiring preparation for accidents. For this purpose, acute and chronic toxicities of nitric acid, sulfuric acid, hydrogen peroxide, and ammonia solution, which can change the physical and chemical properties of soil to Paronychiurus kimi(Collembola) were investigated. The pH of artificial soil spiked with a series of test chemical concentrations was also measured. The pH of soil spiked with 10,000 mg kg^-1 of soil nitric acid, sulfuric acid, hydrogen peroxide, and ammonia solution were 2.86, 2.72, 7.18 and 9.69, respectively. The 28-d LC₅₀ of nitric acid, sulfuric acid, hydrogen peroxide and ammonia solution were 2,703, 5,414, 3,158 and 859 mg kg^-1 soil dry wt., respectively and 28-d EC₅₀ were 587, 2,148, 1,300 and 216 mg kg^-1 soil dry wt., respectively. These results indicated that the mortality and juvenile production of P. kimi were influenced by not only the soil pH but also by the reduced organic content and products produced by the reaction of soil with the tested chemicals. Given the fact that most substances requiring preparation for accidents can change soil characteristics, assessment and restoration methods that take into account changes in soil properties are needed for accurate decision making after chemical accidents.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.2
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• pp.115-122
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• 2002

In this study, the effects of alfalfa hay included in different ratios of 60%(A), 50%(B), 40%(C) and 30%(D) for the diets of young weaned Korean native goats were investigated on feed intake, digestibilities of nutrients, nitrogen retention, average daily gain and feed efficiency. Crude protein contents of experimental diets were 18% in all treatments. The contents of ADF, NDF and crude ash were higher in A as 26.1, 37.0 and 9.0% compared to the lowest values in D of 20.3, 30.4 and 6.6%. However the contents of non-structural carbohydrates was in the opposite tendency. Daily feed intake (DM) was highest in A (414.4g) and B (417.7g) and significantly (p<0.05) lower in D(362.6g). Dry matter intake per metabolic basal weight (DM g/kg of $BW^{0.75}$ ) were highest in A(73.9g) and lowest in D(64.0g). Average daily gain and feed efficiencies were in the range of 33.3~48.7g and 8.1~13.4% respectively with no statistical differences, however with the increasing trends according to higher percent of roughage in the diets. Digestibilities of dry matter (DM), organic matter (OM), crude protein (CP), ADF, NBF, crude ash (CA) and non-structural carbohydrates (NSC) were in the tendency of becoming higher according to higher ratios of concentrate but becoming lower according to higher ratio of alfalfa hay in the diets fed to Korean native goats. Nitrogen retention was lowest in A (1.8g, 15.5%) and highest in D (2.7g, 25.7%). In overall, inclusion of 30~40% alfalfa hay as a roughage in the diets of weaned Korean native goats was superior to the higher rates of inclusion of alfalfa hay in aspects of average daily gain and feed efficiency. The fixed 18% of crude protein content in the diets was efficient for the growth of weaned goats.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.437-446
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• 2012

As a part of establishing suitability classification for forage production, use of the national soil and climate database was attempted for Italian ryegrass (Lolium multiflorum Lam., IRG) in Gangwon Province. The soil data base were from Heugtoram of the National Academy of Agricultural Science, and the climate data base were from the National Center for Agro-Meteorology, respectively. Soil physical properties including soil texture, drainage, slope available depth and surface rock contents, and soil chemical properties including soil acidity and salinity, organic matter content were selected as soil factors. The crieria and weighting factors of these elements were scored. Climate factors including average daily minimum temperature, average temperature from March to May, the number of days of which average temperature was higher than $5^{\circ}C$ from September to December, the number of days of precipitation and its amount from October to May of the following year were selected, and criteria and weighting factors were scored. The electronic maps were developed with these scores using the national data base of soil and climate. Based on soil scores, the area of Goseong, Sogcho, Gangreung, and Samcheog in east coastal region with gentle slope were classified as the possible and/or the proper area for IRG cultivation in Gangwon Province. The lands with gentle or moderate slope of Cheolwon, Yanggu, Chuncheon, Hweongseong, Pyungchang and Jeongsun in west side slope of Taebaeg mountains were classified as the possible and/or proper area as well. Based on climate score, the east coastal area of Goseong, Sogcho, Yangyang, Gangreung and Samcheog could be classified as the possible or proper area. Most area located on west side of the Taebaeg mountains were classified as not suitable for IRG production. In scattered area in Chuncheon and Weonju, where the scores exceeded 60, the IRG cultivation should be carefully managed for good production. For better application of electronic maps.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.196-202
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• 2009

The effects of the salts fortified with seaweed functional components on blood pressure, serum minerals, and hematochemicals in spontaneously hypertensive rats (SHR/NCrj) and normotensive rats (WKY/NCrj) were investigated. SHR and WKY rats were assigned to four groups, with 8 and 6 rats in each group: laver salt (A), fucoidan+laver high salt (B), fucoidan + laver low salt (C) and refined salt as a control (D). The final blood pressure (BP) of SHR and WKY species in contrast with reference BP were low in groups A and C as compared with control group. In terms of serum mineral content, $Na^+$ levels were similar in SHR and WKY, but $K^+$ levels were higher in the group B in SHR. Serum triglyceride levels were lower in groups A and C, but the levels of HDL- and LDL- cholesterol were significantly higher and lower in group A than those of controls, respectively (p<0.05). These results demonstrated that the salts fortified with laver might suppress blood pressure in rats, and also may improve mineral and lipid metabolism.