• Korean Journal of Environment and Ecology
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• v.17 no.2
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• pp.144-152
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• 2003

The purpose of this study was to investigate the effects of lime fertilization and light intensity on beech regeneration strategy in a mature beech forest(ca. 150 years old) gaps, which was located in the soiling areas Germany, where the soil is an acid brown earth. For the experiment canopy gaps of 30m diameter were cut, and one canopy gap remained as untreated while the other was limed(3t dolomite h $a^{-1}$). Soil chemistry, soil water potential, light intensity(PAR), ground vegetation, beech seedlings and mycorrhiza were investigated along transect from the stands into gaps to the north. The results of this study are followings: 1) In the limed gap, soil chemistry was greatly improved and a vigorous herb layer developed as compared to the unlimed gap. 2) Development and growth of the beech seedlings in the unlimed gap were generally deficient. Specially, developments of lateral roots were very lack. 3) Through the lime fertilization, the minerals contents of beech leaves such as calcium(Ca) and magnesium(Mg) were increased, while manganese(Mn) was decreased. There was antagonism between potassium(K) and calcium(Ca) or magnesium(Mg). 4) The relative mycorrhiza frequency(RM) in beech seedlings of the southern edge was very higher than that of the middle part, and through the lime fertilization extension of the species Laccaria amethystina appeared clearly. The results of this study showed that lime fertilize in forest, where the soil is acid, will be necessary..

• Korean Journal of Poultry Science
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• v.42 no.3
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• pp.267-274
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• 2015

Peat moss has been found to be useful as a plant growth substance, fertilizer, and soil solution. It is not known, however, whether dietary peat moss affects performance in broilers. In the present study, we investigated the effects of dietary peat moss as a feed ingredient in broilers. Experimental diets were prepared by mixing basal feed with PM at 0.0, 0.2, 0.4, 0.8, and 1.6%. In experiment 1, 150 14-day-old Ross broiler chicks were housed for 2 weeks in 15 pens that were randomly assigned into five groups (0.0%, 0.2%, 0.4%, 0.8% and 1.6% PM). Dietary peat moss at 0.2% and 0.4% significantly increased the water intake, body weight, weight gain and feed efficiency compared with the control (0.0% PM, P<0.05) but did not affect feed intake. Higher levels of PM (0.8 and 1.6%) significantly decreased feed intake, body weight and weight gain. In experiment 2, 198 7-day-old Ross chicks were housed for 3 weeks in nine pens that were randomly assigned into three groups (0.0%, 0.2% and 0.4% PM). When the broilers were fed with dietary peat moss for 3 weeks, the peat moss effects disappeared. The results of the current study show that low amounts of dietary peat moss may exert beneficial effects on performance in broilers.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.2
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• pp.81-92
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• 2001

According to analyses of high-resolution seismic profiles (air gun, sparker, and SBP) and a deep-drill core(YSDP 105) in the mid-eastern Yellow Sea, stratigraphic and geoacoustic models have been established and seismo-acoustic modeling has been fulfilled using ray tracing of finite element method. Stratigraphic model reflects seismo-, litho-, and chrono-stratigraphic sequences formed under a significant influence of Quaternary glacio-eustatic sea-level fluctuations. Each sequence consists of terrestrial to very-shallow-marine coarse-grained lowstand systems tract and tidal fine-grained transgressive to highstand systems tract. Based on mean grain-size data (121 samples) of the drill core, bulk density and P-wave velocity of depositional units have been inferred and extrapolated down to a depth of the recovery using the Hamilton's regression equations. As goo-acoustic parameters, the 121 pairs of bulk density and P-wave velocity have been averaged on each unit of the stratigraphic model. As a result of computer ray-tracing simulation of the subsurface strata, we have found that there are complex ray paths and many acoustic-shadow zones owing to the presence of irregular layer boundaries and low-velocity layers.