• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.1
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• pp.35-40
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• 1983

This study was conducted to investigate the effect of some kinds of tree litters covered the soil surface on the germination, establishment, sward composition, and herbage production of the grasses sown by the oversowing method. The litters were leaves of Pinus rigida Miller, Quercus variabilis Blume, Larix leptolepis Gord, and Alnus hirsuta Rupr. The results obtained were as follows; 1. In the Petri dish, germination was affected by grass species and kinds of litters, especially the percolate from Pinus litter seriously suppressed the early germination of small size seeds such as ladino clover and timothy. 2. In the pot, establishment was slightly suppressed in ladino and timothy by the percolate from Pinus litter, while in others it was decreased relatively. 3. Among the 6 species investigated, the small size seeds of ladino clover and timothy and the large size seeds of red clover, they could be early put into the litter spaces and established well. 4. In Larix litter, the establishment percentage of all species were decreased seriously owing to low moisture retention capacity. 5. Grass height and root length were different in kinds of litters and species. 6. The percentages of establishment on each surface treatments of burning, treading, raking, and the control under Quercus tree were 36, 46, 37, and 31%, respectively. 7. The sward percentage of oversown grasses and legumes was 57.8% in burning, 70.9% in treading, 59.6% in raking, and 54.0% in the control. 8. Treading treatment was most effective to destroy existing vegetation and improve soil-seed contact when oversowing and showed the best result. 9. Yield of dry matter per unit area in treading treatment was higher (p<0.05) than those of the other treatments. The above experimental results suggest the importance of direct oversowing on the litters in the mountainous land and forest land.

• Journal of Korean Society of Forest Science
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• v.103 no.3
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• pp.321-338
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• 2014

In the Natural Monument (No. 432) Jeju Sanghyo-dong Cymbidium kanran Habitat (39 ha), flora, vegetation diversity, stand structure, mirco-climate, canopy openness, light environment and soil temperature and moisture were quantified from Oct. 2013 to Feb. 2014. Compare to Seogwipo-si, daily mean temperature ($5.7^{\circ}C$) and moisture (75.8%) in study area were lower at $3.3^{\circ}C$ and 15%, respectively. Mean soil temperature and moisture were $16.5^{\circ}C$ and 37.3%, respectively, and mean litter layer depth (n = 81) was 4.3 cm. Mean canopy openness and light availability at forest floor were 15.5% and $8.5mol{\cdot}m^{-2}{\cdot}day^{-1}$, respectively. Total of 22 species including vascular and bryophyte plants and 6 vegetation group were observed. Castanopsis siebildii was dominant species in study area, and density and basal area were 1,777 stem/ha and $90.3m^2/ha$.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.2
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• pp.101-109
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• 2003

The study area, Kwangneung Experiment Forest (KEF) is located on the west-central portion of Korean peninsula and belongs to a cool-temperate broadleaved forest Bone. At the old-growth deciduous forest near Soribong-peak (533.1 m) in KEF, we have established a 1 ha permanent plot ($100m{\times}100m$) and a flux tower, and the site was registered as a KLTER(Korean long-term ecological research network) and DK site of KoFlux. In this site, we made a stemmap of trees and analyzed forest stand structure and physical and chemical soil characteristics, and estimated carbon budgets by forest components (tree biomass, soils, litter and so on). Dominant tree species were Quercus serrata and Carpinus laxiflora, and accompanied by Q. aliena, Carpinus cordata, and so on. As a result of a field survey of the plot, density of the trees larger than 2 cm in DBH was 1,473 trees per ha, total biomass 261.2 tons/ha, and basal area $28.0m^2$/ha. Parent rock type is granite gneiss. Soil type is brown forest soil (alfisols in USDA system), and the depth is from 38 to 66 cm. Soil texture is loam or sandy loam, and its pH was f개m 4.2 to 5.0 in the surface layer, and from 4.8 to 5.2 in the subsurface layer. Seasonal changes in LAI were measured by hemispherical photography at the 1.2 m height, and the maximum was 3.65. And the spatial distributions of volumetric soil moisture contents and LAIs of the plot were measured. The carbon pool in living tree biomass including below ground biomass was 136 tons C/ha, and 5.6 tons C/ha is stored in the litter layer, and about 92.0 tons C/ha in the soil to the 30 cm in depth. Totally more than about 233.6 tons C/ha was stored in DK site. These ground survey and monitoring data will give some important parameters and validation data for the forest dynamics models or biogeochemical dynamics models to predict or interpolate spatially the changes in forest ecosystem structure and function.

• Journal of Animal Environmental Science
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• v.11 no.1
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• pp.61-70
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• 2005

A total of 4 trials were conducted to evaluate the nutritional value of food waste-byproduct feeds mixture(FWM) rotary drum-pasteurized and cured, to trace the nutritional flow according to the processing stages and finally to determine the optimal mixing formulation of feed ingredients for the growing pigs. Pasteurizing and curing FWM using a rotary drum drier resulted in little change in chemical composition and 8 to $15 \%$ of dry matter losses. Chemical change was affected by different feed ingredients used in each trial. Curding of FWM was caused probably by high moisture content, starch content and(or) physical characteristics of feed ingredients. The optimal mixing ratio of feed ingredients was food waste 45 : deepstacked broiler litter 10 : bakery by-product 22.5 barley bran 22.5. In conclusion, FWM rotary drum-pasteurized and cured had a satisfactory feed-nutritional value far growing pigs.

• Journal of Plant Biology
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• v.25 no.2
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• pp.83-99
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• 1982

In this study, thirty-two stands in Kwangnung forest located in the central part of Korea were preferentially selected. In each stand, all stems for trees and shrubs were recorded by species and their girths were measured down to 5cm. In addition, several enviromental factors such as field soil pH, field soil moisture, soil compressibility, depth of soil, thickness of litter layer, elevation and basal area were measured. Three soil cores were sampled and various physical and chemcial properties was determined. The vegetational data were subjected to three kinds of multivariate ordination(PO, PCA, RA). The results suggested that Kwangnung forest was consisted of three forest types: coniferous, mixed and broad leaved forest communities. The relation between the stand scores of ordination and several environmental factors were investigated in terms of correlation analysis in order to examine the relationships between the vegetation and certain environmental factors. As a result of this analysis, the amount of sand content in A1 horizon decreased frm the coniferous to broad leaved forest, while maximum field capacity, pore space, exchangeable cations, loss on ignition, soil pH nad the amount of total nitrogen had a tendancy to increase significantly. However, easily soluble phosphorus appeared to have little to do with the forest types. The result of species ordination of centered-standardized PCA suggested that the major successional pathway in Kwangnung forest was; Pinus densifloralongrightarrowQuercus mongolica, Q. serrata, Q. alienalongrightarrowCarpinus laxifloralongrightarrowC. erosa in sequence. This trend is in good agreement with the past studies. In three kinds of ordination (centered PCA, centered-standardized PCA and RA) based on nineteen species and twenty-five stands, the total variances accounted for the first three axes were 77%, 46% and 63% respectively. The estimated beta diversity in Kwangnung forest assumed as a coenocline, was 1.5~1.8 HC. Increasing the effect of the sampling errors on ordination perfermance, this low heterogeneity seems to cause the poor concentration of the total variance. The results from the four kinds of ordination were in good agreement with each other, especially between PO, centered-standardized PCA and RA appeared robust. It seems to be worthy of applying multivariate method for analyzing other forest communities in Korea.

• Korean Journal of Poultry Science
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• v.47 no.4
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• pp.199-210
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• 2020

Footpad dermatitis (plantar surface footpad lesions) is an increasing problem in the global poultry industry, affecting foot quality, overall welfare, and production performance. The growing consumer demand for chicken feet in Asian markets has given poultry companies interest in reducing footpad dermatitis. The lesions are multiply associated with various factors affecting the moisture content of litter such as nutrition, drinker type and management, environmental conditions (e.g., temperature, relative humidity, ammonia levels, ventilation rate), and flock health. This review addresses footpad dermatitis characteristics, causes, and the assessment system to provide a guide for future research.

• Journal of Korean Society of Forest Science
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• v.54 no.1
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• pp.49-59
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• 1981

In order to elucidate the process of plant succession of the Japanese red pine forests caused by pine gall midge, Thecodoplosis japonensis, in the area of Chungbuk and Kyongbuk, 12 study plots, 4 plots from each three districts, were set up. Districts A (Cheongwon)not attacked by this insect, as the check, District B(Gumi) in which the insect outbreak occured 5 years ago, and District C(Yeongdong)in which the insect outbreak occured 10 years ago, were sampled. The surveyed were some environmental factors, the number of woody plants, relative density, relative dominance values, species composition of plots by layer(upper, middle and ground), importance values, species diversity, similarity and dissimilarity index, etc. The results obtained are summarized as follows: The accumulation of litter on the ground was increased with the lengthening the insect damage duration. Through the crown opening and litter accumulation, the light intensity, temperature condition and soil moisture and nutrient content might be altered. According to the changes of species composition were forced. In general, the Genus Quercus, as a compensation species, has sprung up. The relative importance values for Q.aliena, Q.serrata, and Q.variabilis were significantly increased in the insect infested forests. 2. the stand structure and species composition of the insect attacked forest about 5 years later after the outbreak become complex and diverse. However, since this time, the simplicity of these regards become restored up to 10 years after the outbreak. 3. As the synthetic analysis of plant succession process, the relative values calculated from the relative density and the relative dominance values shown the dominant status of Genus Quercus in the heavily damaged forests. In addition, Genus Rhododendron and Genus Lespedeza with higher frequency become the ground vegetation components. They were gradually increased along the time elapsing after the insect out-break. 4. The differences in connection with the soil moisture contents, the organic matter contents which might give some influences to the vegetation change were hardly recognizable statistically among the studied plots by three district groups. We estimated that the annual mean precipitation and the annual mean temperature did not operated any meaningful effects on the vegetation alteration among plots between districts.

• Fire Science and Engineering
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• v.24 no.6
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• pp.1-6
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• 2010

A smoldering ground fire can be a probable cause of reignition of surface fire when transmitted from Fermentation layer to Humus layer with temperature higher than that of ignition. Purpose of this paper is to identify experimental methodology on the potential risk of a smoldering ground fire, which is similar to the real surface fuel bed, and its combustion characteristics. The fuel model designed in this study is composed of 3 layers such as Litter layer, Fermentation layer and Humus layer and 8 Thermocouples are set through 3 layer at each boundary and in between to detect the temperature change and duration of smoldering and propagation velocity. As a result, it was observed that ignition conditions in the boundary between L layer and F layer determined transmission and non-transmisstion to F-H layer. In addition, range of critical humidity at which a smoldering ground fire was transmitted in a material layer was 33~44% and when temperature exceeds $350^{\circ}C$, likelihood of transmission of a smoldering ground fire was high. In the research, the experimental model for multi-layer smoldering ground fire is suggested and information about propagation of smoldering fire, possibility of reignition according to moisture content, propagation velocity and temperature change are obtained, Also, the built-up methods were established to help analyze basic characteristics of smoldering ground fire.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.143-150
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• 2003

Korea has plentiful precipitation but rainfall events concentrate on several months of rainy season in her weather condition. Korea, therefore, experiences drought for a given period every year. Moreover the soil has usually low water holding capacity, as it is composed coarse particles originated from the granite. Response of several oaks and the Korean red pine (Pinus densiflora) on water stress showed that water budget was significant factor determining vegetation distribution. In addition, dehydration level due to cold resistance mechanism of several evergreen plants during the winter season was closely related to their distribution in natural condition. Experimental result under water stress showed that the Korean red pine was very tolerant to desiccation but the seedlings showed high mortality during the dry season. The mortality tended to proportionate to soil moisture content of each site. A comparison between soil moisture content during June when it is severe dry season and moisture content of the culture soil when the pine seedlings reached the permanent wilting point due to water withheld proved that high mortality during the dry season was due to water deficit. Water potential of sample plants measured during the exposure experiment to the air pollutant showed a probability that water related factors would dominate the occurrence of visible damage and the tolerance level of sample plants. In both field survey and laboratory experiment, plants exposed to air pollution showed more rapid transpiration than those grown in the unpolluted condition. The result would due to injury of leaf surface by air pollutants. Aluminum (Al/sup 3+/) increased in the acid soil not only inhibits root growth but also leads to abnormal distribution of root system and thereby caused water stress. The water stresses due to air pollution and soil acidification showed a possibility that they play dominating roles in inducing forest decline additionally to the existing water deficit due to weather and soil conditions in Korea. Sludge, which can contribute to improve field capacity, as it is almost composed of organic matter, showed an effect ameliorating the retarded growth of plant in the acidified soil. The effect was not less than that of dolomite known in widely as such a soil ameliorator. Litter extract contributed also to mitigate the water stress due to toxic Al/sup 3+/. We prepared a model showing the potential interaction of multiple stresses, which can cause forest decline in Korea by synthesizing those results. Furthermore, we suggested restoration plans, which can mitigate such forest decline in terms of soil amelioration and vegetation restoration.

• Korean Journal of Poultry Science
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• v.40 no.3
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• pp.253-262
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• 2013

This experiment was conducted to investigate the effects of floor type and heating system on performance, housing environment and health status of ducks reared in three types of duck house (OD : Open floor house-Direct heating system, OF : Open floor house-Floor heating system and LD : Loft type house-Direct heating system). In OF treatment, PVC pipes were installed for heating under concrete floor and covered with litter. In LD treatment, plastic mesh was installed 50 cm above the floor so that duck's droppings can pass through it. Each treatment had four replicates of 25 birds (Cherry Valley duck breed) per pen. There were no significant differences in weight gain and feed intake of ducks for 6 weeks among all treatments. However, feed conversion ratio in LD was significantly higher (p<0.05) than that in OF. No differences were found in carcass charac- teristics, with the exception of abdominal fat weight where OF were higher than the others. Concentrations of $CO_2$ and $NH_3$ gas in OD were higher than those of OF and LD at 3, 4 and 5 weeks. Moisture content in litter of OF was lower than that of OD. In contrast, the amount of dust in the air was higher in OF than in OD. The amount of fuel used for 6 weeks in LD was lower about 21% than that in OD. Some of unusual symptoms were observed in open floor house and loft type house, such as lying, spraddle legged, twisted ankle and legs, wounded sole, or etc. No components of leukocyte and erythrocyte of blood were significantly different among all treatments. The results of this experiment showed that OF and LD systems had no positive effects on performance of meat type commercial duck. However, there were some positive effects of certain house type for the improvement of environmental condition in duck house for hygienic production. In the future, more research on the effect of various facilities and systems for duck house is needed.