• Journal of Ecology and Environment
• /
• v.36 no.1
• /
• pp.57-63
• /
• 2013

This study compared the antimicrobial activity and total phenolic content of three Pinus plants (Pinus densiflora, P. thunbergii, P. rigida) for the first time. The antimicrobial activity of the water fraction of methanol extract of fresh leaves was stronger than that of fallen leaves at any concentrations. The water fraction of crude methanol extract from fresh leaves of P. thunbergii showed a higher growth inhibitory activity against gram-positive and gram-negative bacteria than that of P. densiflora and P. rigida. The results from the disc diffusion method followed by measurements of minimal inhibition concentration (MIC) indicate that Bacillus subtilis was the most sensitive microorganism with the lowest MIC value. The highest total phenolic content was found in fresh leaves of P. rigida and P. thunbergii. The assay showed that the fresh leaves of the three Pinus plants contained higher total phenolic content than fallen leaves of the three plants. The antimicrobial activity was related with the total phenolic content.

• Journal of Sericultural and Entomological Science
• /
• v.39 no.1
• /
• pp.1-11
• /
• 1997

In relations to cold acclimation, experiment was carried out to understand the seasonal changes in reserve substances of the mulberry. The shoot barks and leaves of three mulberry varieties(Kaeryangppong, Shinilppong and Yongcheonppong) were sampled, after that their reserve substances were analyzed. The cold hardiness of mulberry was investigated by DTA(Differential Thermal Analysis) method. To increase cold hardiness, gibberellin(100 ppm), kinetin(100 ppm) and Jambi 8 were sprayed on the mulberry leaves. After spraying, falling of the leaves of Yongcheonppong occured earier than the other varities. After the first frost, all of treatments except gibberellin were entirely fallen. Growth regulator extended the leaves fallen. After spraying, water of the shoot barks was not showed difference in the content among the treatments, but amino acid, carbohydrate and soluble protein increased from September to October. Starch content of the shoot barks and leaves was maximum in October, but thereafter decreased during wintering stage. In Shinilppong, Jambi 8 spray increased cold hardiness by 1-2$^{\circ}C$ more than no spray. It was concluded that the cold hardiness of the mulberry in midwinter is closely related to the reserve substances with spraying Jambi 8 on the mulberry leaves.

• Journal of Plant Biology
• /
• v.12 no.1
• /
• pp.15-21
• /
• 1969

In this experiment, the litters of each five species of neadle-leaf trees and broad-leaf trees were laid on each pot soils, which had same soil conditions, is the green house and the sil fertility of each pots were determined after four years. Chemical properties among each pot soils under litters of needle-laef trees showed remarkable different values in the pH, base exchange capacity, total exchangeable base, base saturation, organic matter, available phosphorus, exchangeable potassium and calcium, and that of broad-leaf trees showed respectively significant difference. The content of chemical components, such as total exchangeable base, organic matter, total nitrogen, available phosphorus and exchanbeable potassium, between pot soils under litters of the needle-leaf trees and the broad-leaf trees were significant at the 0.01 and 0.05 levels of the statistical probability. The fertility of soil under the influence of decayed fallen leaves is the highest value in the posts of broad-leaves and next to the pots of needle-leaves and the control pots the lowest. The pH value of the soil with various kinds of fallen leaves showed little difference among themselves, but it especially approached in the broad leaves plots gradually to neutral and hte non-treated plot showed acidity. Lespedeza bicolar and Castanea crenata are supposed to contribute to the fertility of soil. Pinus rigida showed excellent exchanged properties of soi. The leaves of Robinia pseudoacacia and Pinus koraiensis did not contribute much to the promotion of fertility of soil.

• Fire Science and Engineering
• /
• v.23 no.5
• /
• pp.24-31
• /
• 2009

Based on fallen leaves of major Korean conifer species 'Pinus densiflora' and major Korean broadleaved species 'Quercus variabilis', this study sought to identify combustion emission gas types and measure their concentration by means of FTIR (Fourier Transform Infrared) spectrometer. As a result, it was found that there were total 13 types of combustion gas detected from fallen leaves of Pinus densiflora and Quercus variabilis, such as carbon monoxide, carbon dioxide, acetic acid, butyl acetate, ethylene, methane, methanol, nitrogen dioxide, ammonia, hydrogen fluoride, sulfur dioxide and hydrogen bromide. Notably, nitrogen monoxide was additionally detected from fallen leaves of Quercus variabilis. It was found that the overall concentration of combustion gas emitted from the fallen leaves of Pinus densiflora was 4.5 times higher than that from fallen leaves of Quercus variabilis. Particularly, it was found that emission concentration of some combustion emission gas types like carbon monoxide, carbon dioxide and butyl acetate exceeded the upper limit of their time-weighted average (TWA, ppm), while the emission concentration of carbon monoxide and carbon dioxide exceeded their short-term exposure limit (STEL, ppm) for both species. Thus, it was found that carbon monoxide and carbon dioxide have higher hazard to health than other gas types, because these two gas types account for higher than 99% of overall gas emission due to combustion of surface fire starting from litter layer in forest.

• Journal of Energy Engineering
• /
• v.23 no.3
• /
• pp.241-246
• /
• 2014

This study is to compare characteristics of saccharification reactions applying to enzymatic hydrolysis of pretreated fallen leaves for bio-ethanol production. It experimented pretreatment of acid, alkaline in the chemical. This experiment includes preteatment of acid and alkaline in chemical, soaking, shaking and autoclaving method, which were applied to biomass. In result, the glucose production from alkaline-NaOH method was 263 mg glucose/ g biomass comparing with them of acid-HCl method. Thus, alkaline-NaOH method is superior than the acid-HCl method for chemical preteatment of fallen leaves. Also, when various chemical treatments were compared, they were all. Based on the results of this study, we found that leaves, one of biomass, are possible in pretreatment and enzymatic hydrolysis process, and they are likely to affect bio-ethanol production in the future.

• The Korean Journal of Community Living Science
• /
• v.17 no.2
• /
• pp.105-112
• /
• 2006

The biodegradability test of bulking agents in feces composting process is conducted to increase the management efficiency for environment-friendly rural toilet developed by National Rural Resource Institute in 2001. In the case study through references and field study, ash, fallen leaves, and wood chips are commonly used in the ecological toilet. Extension officers and farmers prefer rice straw, fallen leaves, and chaff among the rural resources as a bulking agents in the aspect of getting and storage as the result of questionnaire survey. As the result of biodegradability test including the temperature change, $CO_2$ gas production, and C/N ratio change of composting pile under the condition of aerobic composting apparatus, rice straw and chaff are good bulking agents for environment-friendly rural toilet. It is recommended that easy getting materials among the above mentioned materials are used for bulking agents as the region and season in environment-friendly rural toilet.

• Fire Science and Engineering
• /
• v.21 no.3
• /
• pp.41-46
• /
• 2007

The combustion characteristics of surface forest fire fuels was analysed using variable external irradiation level. The characteristics such as ignition time, ignition temperature, critical heat flux and mass loss rate were measured. Fuel samples were exposed to incident heat fluxes from 8 to $50\;kW/m^2$. For the measurement of various combustion characteristics, the size of specimen holder was $100\;mm{\times}100\;mm{\times}12\;mm$ and the fuel samples grinded by electric mill were the fallen leaves of Quercus variabilis and Pinus densiflora. As results, the occurrence of ignition is possible to the heat flux more than $9\;kW/m^2$. The fuel of Pinus densiflora keeps its high temperature longer than that of Quercus variabilis during the combustion process. The results of measurement shows that the maximun and average mass loss rate of Quercus variabilis larger than that of Pinus densiflora.

• Korean Journal Plant Pathology
• /
• v.14 no.6
• /
• pp.676-681
• /
• 1998

Disease incidence of Codonopsis lanceolata was surveyed at the major cultivating fields in Chonbuk province in 1996 to 1997. The main diseases of Codonopsis lanceolata were ovserved as leaf spot caused by Septoria codonopsis, anthracnose by Glomerella cingulata, brown leaf spot by Cercospora sp., rust by Coleosporium koreanum, powdery mildew by Erysiphe sp., Fusarium wilt caused by Fusarium oxyporum, and white root rot by Sclerotium rolfsii. Anthracnose, leaf spot and brown leaf spot occurred severely on leaves from early July to late August. They were caused early fallen leaves. Fusarium wilt and white root rot occurred severely on stem and below the soil line in late August. They resulted in withering to death or chlorosis and fallen of leaves. Disease incidence of Codonopsis lanceolata was also substantially different in occurrence with a method of cultivation in late growth stage. Fusarium wilt and white root rot were more severe with a method of no support cultivation than those with a method of support cultivation with a stick. Fusarium wilt occurred 48.8% in a method of no support cultivation but 3.1% in a method of support cultivation with a stick. And white root rot occurred 18.9% in a method of no support cultivation but 0.3% in a method of no support cultivation with a stick. Thus, it proved that soil-borne diseases could be controlled support cultivation with a stick.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2007.11a
• /
• pp.438-443
• /
• 2007

• The Korean Journal of Ecology
• /
• v.20 no.5
• /
• pp.323-328
• /
• 1997

The monoterpenoids are analysed in leaves and fallen leaves of Pinus species (P. thunbergii, P.. rigida. P. densiflora.). The amount of total monoterpenoids of P. thunbergii was always the highest, and then those of P. rigida and P. densiflora were orderly decreasing (P<0.05). The major monoterpenoids of P. thunbergii, P. rigida and P. densiflora are ${\beta}-pinene$, comphene and sabinene. There was no significant difference among the seasonal variation in monoterpenoids composition (P>0.05), but the concentrations of fenchone and bornyl acetate were varied (P<0.05).