• Journal of Life Science
• /
• v.22 no.8
• /
• pp.1071-1076
• /
• 2012

To investigate the antimicrobial and anti-halitosis effects of Alnus firma extracts and gallic acid (GA) isolated from A. firma, we measured their antimicrobial activities against oral pathogens and their inhibitory effects on the cell adhesiveness and acid production of oral pathogens. In addition, the levels of volatile sulfur compounds were determined by using oral chroma. The dichloromethane (DCM) fraction has broad antimicrobial activity, and the ethylacetate (EA) fraction showed a relatively high level of antimicrobial activity against Streptococcus mutans and Porphyromons gingivalis. Especially, the GA and DCM fractions had significant inhibitory effects on the attachment and acid production of S. mutans and Streptococcus salivarius, respectively. The 2% MeOH extract of A. firma showed a significant inhibitory effect on the production of volatile oral compounds, such as hydrogen sulfide, methyl mercaptan, and dimethyl sulfide, which can cause bad breath and halitosis. Two percent GA also had a significant inhibitory effect on the production of hydrogen sulfide. Our study showed that the active fractions and GA of A. firma could be suitable resources for development as a natural antibiotic agent for the treatment of infectious oral diseases.

• Journal of Ecology and Environment
• /
• v.32 no.4
• /
• pp.267-275
• /
• 2009

To investigate the possible applications of plants to remediate heavy-metal-contaminated soil, a pilot experiment was performed for four years in a reclaimed dredging area using two Alnus species, i.e., Alnus firma and Alnus hirsuta. In a comparison of phytomass of the two species at two different planting densities, the phytomass of Alnus planted at low density was twice as high as that of Alnus planted at high density after four years. The Alnus species showed active acclimation to the heavy-metal-contaminated soil in a reclaimed dredging area. A. hirsuta showed greater accumulation of phytomass than A. firma, indicating that it is the better candidate for the phytoremediation of heavy-metal-contaminated soils. In the pilot system, Alnus plants took metals up from the soil in the following order; Pb > Zn > Cu > Cr > As > Cd. Uptake rates of heavy metals per individual phytomass was higher for Alnus spp. planted at low density than those planted at high density in the pilot system. Low plant density resulted in higher heavy metal uptake per plant, but the total heavy metal concentration was not different for plants planted at low and high density, suggesting that the plant density effect might not be important with regard to total uptake by plants. The quantity of leached heavy metals below ground was far in excess of that taken up by plants, indicating that an alternative measurement is required for the removal of heavy metals that have leached into ground water and deeper soil. We conclude that Alnus species are potential candidates for phytoremediation of heavy-metal- contaminated surface soil in a reclaimed dredging area.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.4 no.1
• /
• pp.12-17
• /
• 2002

This study identified the physiological characteristics of Alnus firma seedlings collected from air polluted industrial complex of Yeosu area with inoculation of nitrogen-fixing nodule. A. firma individuals resistant or sensitive to air pollution stress at the study area were selected. Seeds of the individuals were sown in a pot and inoculated with the nodules collected at the same area about 3 weeks after germination. To compare the inoculation effects, photosynthesis was measured among the A. firma seedlings under 12 inoculation combinations of seed sources and nodule sources. Photosynthetic activities of seedlings from resistant mother trees were obviously higher than those from sensitive mother trees. In general, the seedlings inoculated with nodule of sensitive trees, showed a worse physiological trend on every combination. In this study, inoculation effect was less important factor than seed sources to photosynthetic activities of A. firma. This physiological characteristic seemed to be determined by seed sources rather than nodule sources.

• Journal of Ecology and Environment
• /
• v.39 no.1
• /
• pp.1-10
• /
• 2016

Despite it has been mentioned that the successful restoration in landscape level was achieved in the Young-il soil erosion control project, quantitative evaluation of restored plant communities (Alnus firma as introduced species and Pinus thunbergii as native species) was hardly founded. Light availability, litter and woody debris cover, and forest structure and composition were determined for 500 m² band-quadrat in three forest types. Abiotic factors of Q. serrata stands, as reference forest, and A. firma stands were similar but not for P. thunbergii stands. There were no significant difference on mean stem density (stems ha^-1, H = 3.6, p = 0.162), and the mean basal area of each stand had marginal significance (m² ha^-1, H = 5.7, p = 0.058) among stands as total basal area was higher with the order of A. firma (21.4 m² ha^-1), P. thunbergii (19.8 m² ha^-1) and Q. serrata (16.2 m² ha^-1). Restoration of vegetation structure was more effective in fast-growing and N-fixing A. firma, as introduced species plantation. However, result of MRPP, NMS ordination and ISPAN for herbaceous layer, not for tree and shrub species composition, indicated that restoration of ground vegetation was likely influenced highly from local environment. Propagule availability from landscape context such as connectedness to natural vegetation and management practices in restored isolated stands are available explanations for restoration effects and gaps between restored plantations and secondary oak forest.

• Journal of Korean Society of Forest Science
• /
• v.77 no.2
• /
• pp.229-234
• /
• 1988

To evaluate potential of VA mycorrhizal fungi for promoting growth of nitrogen-fixing trees and efficiency of fungal inoculation in relation to soil fertility and dual inoculation with bacteria, Alnus firma was grown for six months in pots with steam-sterilized soil after inoculation with Glomus mosseae, and Robinia pseudoacacia was grown in the fumigated field after inoculation with native Glomus sp. and Gigaspora sp. In unfertilized Alnus plants, 27% increase in dry weight(or 18% in height) was observed by Glomus inoculation, while plants inoculated with both VA mycorrhiza and actinomycete(crushed nodule inoculum) showed synergistic effect of 83% dry weight increase over uninoculated plants. In fertilized Alnus plants, mycorrhizal inoculation alone or dual inoculation with actinomycete resulted in depression of height and dry weight of plants. In case of Robinia, dual inoculation stimulated height growth by 23% (or dry weight by 25%) over the control in unfertilized field, while 13% more height growth(or 21% more dry weight) was observed in fertilized field. It is concluded that VA mycorrhizae, especially Glomus mosseae, have a potential for growth enhancement in Alnus, that synergistic effect of dual inoculation(mycorrhiza + actinomycete) exists in both Alnus and Robinia, and that responses of these plants to VA mycorrhiza are more pronounced in unfertilized soil.

• Journal of Plant Biology
• /
• v.28 no.1
• /
• pp.9-20
• /
• 1985

Dimensional variation of secondary xylem elements, such as vessel element and fiber, was investigated in root, stem and branch of Alnus hirsuta and A. firma. It is clear that vessel diameter in the root is the widest, next in the stem, and the least in the branch. Length of vessel element among them becomes, however, larger in following sequence; stem, root, and branch, whereas fiber diameter and length are the widest in the root, the second in the stem, and the least in the branch. The size of secondary xylem element at any one level in tree increases from the center (pith) of the organs through a number of annual rings to the outer.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.25 no.4
• /
• pp.123-140
• /
• 1998

The flora of Kunsan Wolmyong park was 77 families, 168 genera, 240 species, 2 subspecies, 35 varieties, 1 formae or 278taxa. Using the Phytosociology method, 12 plant communities were recognized ; Alnus japonica, Pinus densiflora, Pinus thunbergii, Pinus rigida, Castanea crenata, Quercus acutissima, Robinia pseudo-acacia, Alnus hirsuta, Quercus serrata, Aluns firma, Liriope platyphylla and Reynoutria communities. Similarity between different communities was low for most of the cases except for Pinus densiflora, Pinus Thunbergii and Pinus rigida communities kept comparely high with ond another. Species diversity was analyzed by species richness(SR), species diversity index(H') and evenness(J'). Castanea crenata, Robinia pseudo-acacia and Alnus firma communities were higher in SR, H' than the other communities. But Pinus rigida, Quercus acutissima and castanea crenata communities were higher in evenness than the other communities. To investigate the plant community structure and to establish restoration counter plan of a Wolmyeng Park in Kunsan City. As a remedial approach, following is propesed. first, Establishment of an adequate planting plan and development of slope stalilization method by planting native species. second, Sellection of adequate species by planting experiments for pioneer species, native species, and dietary species. third, Landscape planting zones should be managed artificially, the others be managed with ecological approach.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.8 no.2
• /
• pp.107-115
• /
• 2006

To elucidate the relation of leaf development stage to the antioxidative function in leaves of Alnus firma Sieb. et Zucc. growing in polluted areas, we investigated seasonal changes of pigment content and antioxidant enzyme activities from January to June. In abandoned mine and industrial complex areas, antioxidant function against stress of trees was changed with leaf expansion, and antioxidant activity in leaves was highest in June. Among antioxidants, carotenoid, SOD and CAT were correlated with seasonal change. Carotenoid and SOD represented a positive correlation but CAT represented a negative correlation with leaf development. APX and CAT, which remove $H_{2}O_2$, had a complementary function in the antioxidant system. The lowest antioxidant activity was observed in April, and the damage level in leaves, shown as MDA content, was also lowest in April.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.8 no.4
• /
• pp.32-42
• /
• 2005

To investigate the plants invasion process and dominant species in large-scale cutting slopes, slopes elapsed one year to thirteen years after construction had been selected in five counties. The obtained results are summarized as follows : The species of high appearance frequency were Alnus firma, Arundinella hirta, Miscanthus sinensi var. purpurascens, Erigeron cancdensis, Artemisia princeps var. orientalis, Oenothera odorata, Lactuca raddeana, Lactrca indica var. laciniata, Lespedeza bicolor, Youngia sonchifolia, Populus albaglandulosa, and so on. The biological type of identified vascular plants was $Ch-D_1-R_{5-e}$. In time, plant coverage was increased gradually and average of plant coverage was 1.17% in slopes which elapsed one year, 42.44% after six years, 56.67% after eight years, and 69.17% after ten years. The dominant species in the surveyed slopes were covered with Alnus firma, Artemisia princeps var. orientalis, Erigeron cancdensis, Miscanthus sinensi var. purpurascens, Arundinella hirta, Lactuca raddeana, Oenothera odorata, Boehmeria spicata, Kummerowia striata and Artemisia montana of the 59 species. The conditions of location in large-scale cutting slopes are hard to fix and germinate of seeds, and extend plant roots in the slope soil. Hence, the highly appearance species and dominance species of the area will make plant coverage quick and slope stable.

• Journal of Ecology and Environment
• /
• v.34 no.4
• /
• pp.347-355
• /
• 2011

Effects of forest thinning on community level properties have not been understood yet in Korea. We investigated regeneration patterns and trajectories after a disturbance by applying a chronosequence approach. Light availability, litter and woody debris cover, and species composition were determined for twenty 50 m line-transect samples representing a disturbance duration gradient (within 11 years). Environmental factors such as light availability and coverage of woody debris and litter changed abruptly after thinning and then returned to the pre-disturbance state. Although species richness was gained at shrub and ground layer in a limited way in both forests, cover of various functional types revealed diversity in their responses. Notably, Alnus firma stands exhibited a larger increment of cover in woody plants. Ordination analysis revealed different regeneration trajectories between natural and planted stands. Based on ordination analysis, rehabilitated stands showed movement to alternative states compared with natural ones, reflecting lower resilience to perturbation (i.e., lower stability). Our results suggest that community resilience to artificial thinning depends on properties of the dominant species. But to get more explanatory ecological information, longer-term static observations are required.