• The Korean Journal of Ecology
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• v.20 no.3
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• pp.175-179
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• 1997

To explanin allopatric distribution of Carpinus cordata and C. laxiflora in the field the effect of soil flooding on photosynthesis and water relations was tested with field grown saplings. Under the flooding condition stomatal conductance of C. laxiflora decreased markedly from day two after flooding treatment and remanined low throughout the experiment. In contrast, flooding had no effect on stomatal conductance of C. cordata throughout the exper iment. The rate of photosynthesis of C. laxiflora was significantly suppressed under flooding conditions, whereas that of C. cordata was not affected in the flooded condition. On day seven after flooding treatment xylem pressure potential of C. laxiflora significantly decreased. Flooding, however, did not have any effect on the xylem pressure potential of C. cordata throughout the experiment. From these findings it is concluded that there is a difference in resistance to flooding between C. cordata and C. laxiflora and that one of the the factors responsible for allopatric distribution in the two species is flooding.

• Journal of Sericultural and Entomological Science
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• v.20 no.1
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• pp.1-4
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• 1978

The root-out of mulberry saplings has been studied by pour into soil and spray on leaves of the plant growth substances. In addition, the effect of "Rutin", a kind of plant growth hormones has been also studied on promoting the rootability of mulberry scions by dipping the scions at the various concentrations. The results are summarized as follows: (1) It is likely to be effective on acceleration of the rootability resulting in increase of rooting ratio by pour into soil at the concentration of 1 ppm and 10 ppm NAA, 10 ppm and 100 ppm Rutin, and 5000 fold solution of Atonic, respectively (2) Growth of branch is only promoted by leaf spray of 0.5% urea, 0.005% and 0.01% Rutin, and 5000 fold solution of Atonic without increasing the root weight. (3) It seems that 0.05% of Rutin is of practical use, and 0.05% to 0.4% of "Rutin" accelerates the root-out of mulberry scions as well as NAA does.

• Journal of Forest and Environmental Science
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• v.36 no.2
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• pp.91-112
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• 2020

In Ethiopia, dry land vegetation including the fairly intact lowland and western escarpment woodlands occupy the largest vegetation resource of the country. These forests play a central role in environmental regulation and socio-economic assets, yet they received less scientific attention than the moist forests. This study evaluated the woody plant species composition, population structure and carbon sequestration potential of the A. senegal woodland across three distance gradients from the settlements. A total of 45 sample quadrants were laid along a systematically established nine parallel transect lines to collect vegetation and soil data across distance gradients from settlement. Mature tree dry biomass with DBH>2.5 cm was estimated using allometric equations. A total of 41 woody plant species that belong to 20 families were recorded and A. senegal was the dominant species with 56.4 IVI value. Woody plant species diversity, density and richness were significantly higher in the distant plots compared to the nearest plots to settlement (p<0.05). The cumulative DBH class distribution of all individuals had showed an interrupted inverted J-shape population pattern. There were 19 species without seedlings, 15 species without saplings and 14 species without both seedlings and saplings. A significant above ground carbon (5.3 to 12.7 ton ha^-1), root carbon (1.6 to 3.6 ton ha^-1), soil organic carbon (35.6 to 44.5 ton ha^-1), total carbon stock (42.5 to 60.7 ton ha^-1) and total carbon dioxide equivalent (157.7 to 222.8 ton ha^-1) was observed consistently with an increasing of distance from settlement (p<0.05). Distance from settlement had significant and positive correlation with species diversity and carbon stock at 0.64^⁎⁎ and 0.78^⁎⁎. Disturbance intensity may directly influence the variation of species composition, richness and density along the A. senegal woodland. The sustainability of the A. senegal woodland needs urgent protection, conservation and restoration.

• The Korean Journal of Ecology
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• v.16 no.4
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• pp.377-395
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• 1993

Habitat types, community structure and population characteristics of Koelreuteria paniculata were investigated in Mt. Wolak, Chungbuk and Naesokdong, Daegu, which are natural habitats of the species in inland region of Korea, and its origin was discussed. Habitats of Koelreuteria paniculata were classified to 3 types: sand bar formed by the sands flooded in the course of flow of the mountain stream (Type 1). crevice on the rock bed within the mountain stream (Type 2) and crevice of the rock around the edge of mountain stream (Type 3). Most Koelreuteria paniculata communities in Mt. Wolak site were composed of 3 layers of subtree layer, shrub layer and herb layer and that of Daegu site was 4 layers including tree layer. In the floristic composition of the Koelreuteria paniculata community, plants occurring frequently in the wet and open site, such as Zelkova serrata and Fraxinus rhynchoph-vlla showed high frequency. Frequency distribution of diameter at ground surface of Koelreutrria paniculata showed reversed J-shaped type. It was supposed that expansion of Koelreuteria paniculata community in Mt. Wolak site might be accomplished by the flow of the stream. Many saplings capable of becoming a successor of mature trees in Daegu site in near degenerating phase were established on the forest floor of the Koelreuteria paniculata community. From this result, it was supposed that these saplings originated from the seeds dispersed from a seed tree might form the Koelreuteria paniculata community of the next generation. On the other hand, the origin of Koelreutevia paniculata in inland sites was explained by two hypotheses: the one was that Koelreuteria paniculata might be transplanted by human and the other was that the present site might be native habitat of the community.

• Journal of Sericultural and Entomological Science
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• v.27 no.1
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• pp.12-17
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• 1985

soil survey and chemical analysis on mulberry nursery garden were carried out to study the causes of the non-sprouting phenomenon occured seriously in Buy and Ogchun in 1983 and Sangju in 1984. In addition, 115 nursery garden soils taken from 21 sapling produsers in Chungbuk province were analyzed in 1984. The results were as follows, 1. Symptom of dead saplings was the highest in boron deficiency by 59% and the lowest in rot symptom. The rest of saplings by 34.9% were not detected any symptom. 2. The nursery gardens showen non-sprouting phonomenon were located along the stream. As the result, soil depth was shallow, around 20cm deep and subsoil composed with coarse sand and gravels. 3. Nursery soils were mostly strong acid, low in Ca and Mg content, especially B, whereas available phosphorus and potassium were abundant at some gardens, and deficient at others. 4. Application of red earth or borax to nursery garden, especially to paddy, increased sprouting rate. 5. Paddy nursery garden occupied by 52.8% of 60.8ha of total garden area in Chungbuk province. Ninty point five percent of the nursery garden was lower in pH than 6.5, 87.0% lower in K than 0.5me/100g, 40.8% lower in Ca than 6.5me/100g, 94.8% lower in Mg the 2.00me/100g 99.1% lower in B than 0.3ppm.

• Journal of Sericultural and Entomological Science
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• v.36 no.2
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• pp.102-109
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• 1994

Profitability was analysed in the fields of various planting densities from 1,666 trees/10a to 4,166 with mulberry grafts or conventional saplings under the consideration of leaf yield and quality. Leaf yield per tree decreased with the higher planting densities. Seasonal and total leaf yield per area, however, increased by 20 to 63% as a mean for 3 years in the densities of 2,083~4,166 trees per 10a than in the conventional density of 1,666 trees per 10a. The increase in leaf yield per area was not so high in the densities over 2,083. Leaf yield in the sapling plots was a little higher than that in the graft plots. Topping of shoot tip affected neither on the branch length nor on yield. Yield was higher in the planting spacing with single raws than in that with double raws. Quality of leaves in the densities from 2,083 to 3,333 trees per 10a was relatively good judged based on the results of the pupation rate and cocoon yield and quality.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.196-206
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• 2020

Background: The Himalayan forests are of great importance to sustain the nature and community resource demands. These forests are facing pressures both from anthropogenic activities and ongoing global climatic changes. Poor natural regeneration has been considered a major problem in mountainous forests. To understand the population structure and regeneration status of Larix (Larix griffithiana and Larix himalaica), we conducted systematic vegetation surveys in three high-altitude valleys namely Ghunsa (Kanchenjunga Conservation Area, KCA), Langtang (Langtang National Park, LNP), and Tsum (Manaslu Conservation Area, MCA) in Nepal Himalaya. The average values of diameter at breast height (DBH), height, and sapling height were compared for three sites and two species using Kruskal-Wallis test. Population structure was assessed in terms of proportion of seedlings, saplings, and trees. Regeneration was analyzed using graphical representation of frequencies of seedlings, saplings, and trees in histograms. Results: The results showed that the population structure of Larix in terms of the proportion of seedling, sapling, and tree varied greatly in the three study areas. KCA had the highest record of seedling, sapling, and tree compared to other two sites. Seedlings were the least among three forms and many plots were without seedlings. We found no seedling in MCA study plots. The plot level average DBH variation among sites was significant (Kruskal-Wallis χ² = 7.813, df = 2, p = 0.02) as was between species (Kruskal-Wallis χ² = 5.9829, df = 1, p = 0.014). Similarly, the variation in average tree height was significant (Kruskal-Wallis χ² = 134.23, df = 2, p < 0.001) among sites as well as between species (Kruskal-Wallis χ² = 128.01, df = 1, p < 0.001). All the sites showed reverse J-shaped curve but more pronounced for KCA and MCA. In comparing the two species, Larix griffithiana has clear reverse J-shaped diameter distribution but not Larix himalaica. Conclusion: The varied responses of Larix manifested through regeneration status from spatially distinct areas show that regeneration limitations might be more pronounced in the future. In all the three studied valleys, regeneration of Larix is found to be problematic and specifically for Larix griffithiana in MCA and Larix himalaica in LNP. To address the issues of disturbances, especially serious in LNP, management interventions are recommended to sustain the unique Himalayan endemic conifer.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.141-147
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• 2014

Pinewood nematode (PWN: Bursaphelenchus xylophilus) is known to kill pine tree species that are indigenous to countries where the pest was inadvertently imported, but some cultures from the extraction of dead pines do not damage trees. Experiments were conducted to examine the effect of pre-inoculation of these low-pathogenic pinewood nematode on resistance of pine trees against the pest species. The pre-inoculated pine saplings showed induced resistance which lasted for a year, and repeated inoculation of these low-pathogenic nematodes enhanced tree resistance. All nematode samples extracted from dying or dead pines that had been killed not more than three months before the extraction were pathogenic, and most of those extracted from pines that had been killed 2-3 years before were low-pathogenic. When inoculated in pine saplings, number of low-pathogenic nematodes settled, as studied two days after inoculation, was not different from that of pathogenic ones. However, as studied after 30 days of inoculation, rate of reproduction in low-pathogenic nematodes was far lower than that of pathogenic nematodes. The rate of reproduction of several nematode isolates growing on fungal mat media of Botrytis cinerea varied, but three of four low-pathogenic isolates showed same level of reproduction rates as pathogenic ones.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.3
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• pp.188-196
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• 2014

This study aimed to understand the nutrient absorption, usage and allocation of Carpinus cordata in different soil and light environments. Seasonal changes of foliar nitrogen, phosphorous, chlorophyll contents, leaf mass per area (LMA) and nutrient retranslocation rates were investigated for C. cordata saplings growing in a natural deciduous broadleaved forest and an Manchurian fir (Abies holophylla) plantation in Gwangneung, Kyunggido. The deciduous forest had lower leaf area, higher light penetration, and better soil fertility than the Manchurian fir forest. However, available soil phosphorous content in the deciduous forest was only one third of that in the Manchurian fir forest, which caused lower foliar phosphorous content and higher P retranslocation rate of C. cordata in the deciduous forest than that in the Mancurian fir forest. Soil nitrogen contents in the deciduous forest were higher than that in the Manchurian fir forest, however, no differences in foliar nitrogen content and retranslocation rate in C. cordata between the two stands were found. C. cordata in the Manchurian fir forest with high LAI throughout a year, had lower LMA, foliar nitrogen content and chlorophyll a/b, while had higher total chlorophyll content and chlorophyll/N than that in the deciduous forest. These results implied C. cordata under different environments are using different strategies for nutrient use and allocations.

• Journal of Ecology and Environment
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• v.41 no.6
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• pp.152-164
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• 2017

Background: Natural regeneration of seedlings as well as saplings of Korean fir has been significantly impacted by the browsing from the early stages of their development, potentially, by roe deer for the last two to three decades at the study site since late 1980s. This study was carried out to investigate current status of the disturbance in the seedling development of Korean fir (Abies koreana) on Mt. Hallasan, Jeju Island, Korea. Methods: Field survey was carried out during June and August in 2016 to measure the characteristics of study site and understory vegetation by applying systematic sampling to 125 plots of $5m{\times}5m$ quadrat located on eastern slope of the mountain. Correlation and regression analyses were applied to the variables quantified from the data sets using the SAS software. Results: No saplings with their diameters at breast heights smaller than 5.0 cm were found at the study site indicating the serious disturbance in the natural regeneration of Korean fir at the study site. No seedlings with their heights taller than 36.0 cm were found at the study site indicating even more serious disturbance during earlier stage of the natural regeneration of Korean fir at the study site. A total of 616 individuals of the seedlings of Korean fir were found at 54 out of 125 sampling plots. One hundred thirty-eight seedlings (22.4%) out of 616 individual seedlings have the vestiges for being grazed, potentially, by roe deer. Conclusions: Due considerations should be given to the effects of browsing of the seedlings by roe deer to promote the natural regeneration of Korean fir, ultimately to restore Korean fir. It is needed for the managers of the forest to install fences around the forest area. Exclosure experiments as well as enclosure experiments of different densities of browsing should be carried out. In addition, treatment with different densities of Jeju dwarf bamboo should also be included in the experiment on Mt. Hallasan National Park, Jeju Island, Korea.