• Journal of Korean Society of Forest Science
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• v.29 no.1
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• pp.20-53
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• 1976

For the purpose of detecting the capability of the trees to resist air pollution and of determining the tree species best suited for purification of polluted air, particularly with regard to $SO_2$ contamination, six following ornamental tree species were selected as experimental materials: i.e., Hibiscus syriacus L., Ginkgo biloba L., Forsythia koreana Nak., Syringa dilatata Nak., Larix leptolepis Gordon, and Pinus rigida Miller. The susceptiblities of the trees were observed and analyzed on the basis of area ratio of smoke injury spots to the total leaf area. The results of the experiments are as follows: I. The Susceptibilities to Sulfur Dioxide. (1) The decreasing order of tolerance to $SO_2$ by species was as follows: 1. Hibiscus syriacus 2. Ginkgo biloba, 3. Forsythia koreana, 4. Syringa dilatata, 5. Larix leptolepis, and 6. Pinus rigida. In general, Hibiscus syriacus and Ginkgo biloba can be grouped as the most resistant and Larix leptolepis and Pinus rigida as the least resistant and Forsythia koreana and Syringa dilatata as of intermediate resistance. (2) The sulfur content of the leaves treated by $SO_2$ increased in proportion to the increase of the concentration of the fumigation. The content in the coniferous species proved to be less than that of the broad-leaved species, but Ginkgo biloba proved to contain as much sulfur as broad-leaved species. (3) The earlier-stage leaves fumigated in June with the $SO_2$ concentration up-to-l-ppm showed that sulfur content increases in proportion to the increase of the concentration of the fumigation, but the difference between concentration was not so significant. (4) The later-stage leaves fumigated in October showed higher sulfur content than the earlier stage leaves, and a wider range of difference in sulfur content was detected among different concentrations. The limit of fumigation resulting in culmination of sulfur absoption in broad-leaved species, such as Syringa dilatata, Hibiscus syriacus, and Forsythia koreana proved to be around 0.6 ppm. (5) Due to the sprouting ability and the adventitious bud formation, the recovery from $SO_2$ fumigation was prominent in Hibiscus syriacus, Syringa dilatata, and Forsythia koreana. (6) The differences in the smoke spot color were recognized by species: namely, dirt-brown in Syringa dilatata, brilliant yellowish-brown in Pinus rigida and Ginkgo biloba, whitish-yellow in Hibiscus syriacus and reddish-brown in Forsythia koreana. (7) The leaf margins proved to be most susceptible, and the leaf bases of the mid-rib most tolerant. In both Ginkgo biloba and Larix leptolepis, the younger leaves were more resistant to $SO_2$ than the older ones. II. The ulfur Content of the Leaves of the Ornamental Trees Growing in the City of Seoul. (1) The sulfur contents in the leaves of the Seoul City ornamental trees showed a remarkably higher value than those of the leaves in the non-polluted areas. The sulfur content of the leaves in the non-polluted area proved to be in the following descending order: Salix pseudo-lasiogyne Leveille, Ginkgo biloba L., Alianthus altissima swingle, Platanus orientalis L., and Populus deltoides Marsh. (2) In respect to the sulfur contents in the leaves of the ornamental trees in the city of Seoul, the air pollution proved to be the worst in the areas of Seoul Railroad Station, the Ahyun Pass, and the Entrance to Ewha Womans University. The areas of Deogsu Palace, Gyeongbog Palace, Changdeog Palace, Changgyeong Park and the Hyehwa Intersection were least polluted, and the areas of the East Gate, the Ulchi Intersection and the Seodaemun Intersection are in the intermediate state.

• Journal of Korean Society of Forest Science
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• v.101 no.3
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• pp.344-355
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• 2012

This study was conducted to analyze on the operational time and productivities of logging operations in whole-tree logging operation system by tower-yarder and swing-yarder, and in cut-to-length logging operation system by excavator with grapple in order to establish the efficient logging operation system and to spread logging operation technique. In the analysis of operational time, in case of whole-tree logging operation system, the felling time was 46.6 sec/cycle by chain saw, the yarding time was 480.6 sec/cycle by tower-yarder, the yarding time was 287.4 sec/cycle by swing-yarder and the bucking time was 155.14 sec/cycle by chain saw. In case of the cut-to-length logging operation system, the felling and bucking time was 225.65 sec/cycle by chain saw, the cut-to-length extraction time was 4,972 sec/cycle by excavator with grapple, the branches and leaves extraction time was 3,143 sec/cycle by excavator with grapple. The forwarding time was 4,688 sec/cycle by wheel type mini-forwarder, the forwarding time was 2,118 sec/cycle by excavator with grapple and small forwarding vehicle. In the analysis of operational productivities, in case of whole-tree logging operation system, the average felling performance was $57.89m^3/day$ by chain saw, the average yarding performance was $20.3m^3/day$ by tower-yarder, $31.55m^3/day$ by swing-yarder respectively, the average bucking performance was $20.3m^3/day$ by chain saw. In case of the cut-to-length logging operation system, the average felling and bucking performance was $11.96m^3/day$ by chain saw, the average cut-to-length extraction performance was $34.75m^3/day$ by excavator with grapple, the average branches and leaves extraction performance was $37.66m^3/day$ by excavator with grapple, the average length of operation road construction was 73.8 m/day by excavator with grapple. The average forwarding performance by wheel type mini-forwarder and the average forwarding performance by excavator with grapple and small forwarding vehicle was $15.73m^3/day$ and $65.03m^3/day$, respectively.

• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.669-681
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• 2023

Studies have tried to apply remote sensing technology, a non-destructive survey method, instead of the existing destructive survey, which requires relatively large labor input and a long time to estimate chlorophyll content, which is an important indicator for evaluating the growth of fruit trees. This study was conducted to non-destructively evaluate the chlorophyll content of pear tree leaves using unmanned aerial vehicle-based hyperspectral imagery for two years(2021, 2022). The reflectance of the single bands of the pear tree canopy extracted through image processing was band rationed to minimize unstable radiation effects depending on time changes. The estimation (calibration and validation) models were developed using machine learning algorithms of elastic-net, k-nearest neighbors(KNN), and support vector machine with band ratios as input variables. By comparing the performance of estimation models based on full band ratios, key band ratios that are advantageous for reducing computational costs and improving reproducibility were selected. As a result, for all machine learning models, when calibration of coefficient of determination (R²)≥0.67, root mean squared error (RMSE)≤1.22 ㎍/cm², relative error (RE)≤17.9% and validation of R²≥0.56, RMSE≤1.41 ㎍/cm², RE≤20.7% using full band ratios were compared, four key band ratios were selected. There was relatively no significant difference in validation performance between machine learning models. Therefore, the KNN model with the highest calibration performance was used as the standard, and its key band ratios were 710/714, 718/722, 754/758, and 758/762 nm. The performance of calibration showed R²=0.80, RMSE=0.94 ㎍/cm², RE=13.9%, and validation showed R²=0.57, RMSE=1.40 ㎍/cm², RE=20.5%. Although the performance results based on validation were not sufficient to estimate the chlorophyll content of pear tree leaves, it is meaningful that key band ratios were selected as a standard for future research. To improve estimation performance, it is necessary to continuously secure additional datasets and improve the estimation model by reproducing it in actual orchards. In future research, it is necessary to continuously secure additional datasets to improve estimation performance, verify the reliability of the selected key band ratios, and upgrade the estimation model to be reproducible in actual orchards.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.36 no.3
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• pp.115-127
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• 2018

This study was attempted to find out the value of cultural assets through the clear diagnosis and prescription of the dead and weakness factors of the Population of Retusa Fringe Trees in Pyeongji-ri, Jinan(Natural Monument No. 214), The results are as follows. First, Since the designation of 13 natural monuments in 1968, since 1973, many years have passed since then. In particular, despite the removal of some of the buried soil during the maintenance process, such as retreating from the fence of the primary school after 2010, Second, The first and third surviving tree of the designated trees also have many branches that are dead, the leaves are dull, and the amount of leaves is small. vitality of tree is 'extremely bad', and the first branch has already been faded by a large number of branches, and the amount of leaves is considerably low this year, so that only two flowers are bloomed. The second is also in a 'bad'state, with small leaves, low leaf density, and deformed water. The largest number 1 in the world is added to the concern that the s coverd oil is assumed to be paddy soils. Third, It is found that the composition ratio of silt is high because it is known as '[silty loam(SiL)]'. In addition, the pH of the northern soil at pH 1 was 6.6, which was significantly different from that of the other soil. In addition, the organic matter content was higher than the appropriate range, which is considered to reflect the result of continuous application for protection management. Fourth, It is considered that the root cause of failure and growth of Jinan pyeongji-ri Population of Retusa Fringe Trees group is chronic syndrome of serious menstrual deterioration due to covered soil. This can also be attributed to the newly planted succession and to some of the deaths. Fifthly, It is urgent to gradually remove the subsoil part, which is estimated to be the cause of the initial damage. Above all, it is almost impossible to remove the coverd soil after grasping the details of the soil, such as clayey soil, which is buried in the rootstock. After removal of the coverd soil, a pestle is installed to improve the respiration of the roots and the ground with Masato. And the dead 4th dead wood and the 5th and 6th dead wood are the best, and the lower layer vegetation is mown. The viable neck should be removed from the upper surface, and the bark defect should undergo surgery and induce the development of blindness by vestibule below the growth point. Sixth, The underground roots should be identified to prepare a method to improve the decompression of the root and the respiration of the soil. It is induced by the shortening of rotten roots by tracing the first half of the rootstock to induce the generation of new roots. Seventh, We try mulching to suppress weed occurrence, trampling pressure, and soil moisturizing effect. In addition, consideration should be given to the fertilization of the foliar fertilizer, the injection of the nutrients, and the soil management of the inorganic fertilizer for the continuous nutrition supply. Future monitoring and forecasting plans should be developed to check for changes continuously.

• Korean Journal of Soil Science and Fertilizer
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• v.29 no.4
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• pp.378-384
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• 1996

This study was conducted to investigate the influence of root zone temperature on the growth of shoot and root and the mineral contents in leaf of 'Fuji/M26' apple tree. Shoot growth and enlargement of trunk girth increased linearly with increasing root zone temperature. Fresh and dry weight of root reached maximum at $35^{\circ}C$. Water content of root increased with rising root zone temperature. The chlorophyll content of leaves showed insignificant difference with root zone temperature. Leaf water potential was high at $35^{\circ}C$ at 15 day after treatment but 60 day after treatment this was decreased. The nitrogen content of the leaves was not different by root zone temperature whereas the phosphorus content of the leaves was increased at $30^{\circ}C$ in 1993 and at $25^{\circ}C$ in 1994. The potassium content of the leaves reached a maximum at $30^{\circ}C$ in 1993 and $25^{\circ}C$ in 1994. In 1994 the calcium content of the leaves was increased with rising root zone temperature and with lengthening duration of treatment but no such differences were found in 1993. The magnesium content of the leaves was highest at $25^{\circ}C$ in 1993 and at $20^{\circ}C$ in 1994. The nitrogen and potassium content of the roots were increased linearly with root zone temperature in 1993 and 1994 and the magnesium and phosphorus content of the roots were high at $35^{\circ}C$ in 1994 but no such differences were found in the calcium content of the roots.

• Korean Journal of Environmental Agriculture
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• v.18 no.2
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• pp.135-139
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• 1999

A new effective and economic method was developed, removing interferences such as chlorophyll and lipid from leaves with small amounts of reagents and solvents in order to analyse PAHs(Polycyclic Aromatic Hydrocarbons). The extract from a soxhlet containing $4{\sim}5g$ of leaves and 100ml of dichlormethane and refluxed for 20 hrs was concentrated and eluted with 60ml of a hexane:dichloromethane (1:1) mixture through a column of 9mm wide inner diameter and 130mm long, packed from the bottom with 2.5g of $Al_2O_3$, 1.5g of $SiO_2$and 2g of anhydrous $Na_2SO_4$. The eluent was concentrated and loaded on a GPC column of 20mm wide inner diameter and 280mm long, packed with 12g of Bio-beads. The column was washed with 37ml of the hexane:dichloromethane(1:1) mixture. Another 43ml of the mixture was eluted as a PAH fraction and collected. This eluent was concentrated under gentle nitrogen to $50{\mu}l$ and analysed using GC-MS. The recoveries, obtained by comparing with the amounts of the internal standards of deuterated PAHs were $43.3{\sim}107.5%$(RSD $2.2{\sim}9.5%$).

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.835-848
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• 2015

In the past, Korea had many kinds of jeupjang (succulent jang), a rapidly maturing original Korean jang (fermented soybean paste) of which there is no record in Chinese cookbooks. However, this local delicacy has almost been forgotten. Therefore, we looked for information about jeupjang in cookbooks written prior to the Joseon Dynasty in Korea (1392~1910) and in the 1950s. Among the recipes, there were 34 jeupjangs prepared with vegetables, such as eggplant and cucumber, and 9 without. The main ingredients of jeupjang are soybean, bran (wheat crust), and barley, and wild wheat is also used. Jeupjang is made in small portions to expedite its rapid maturation, but the most common form is egg-shaped, and there is also a flat or round, hilt-shaped version. In most cases, jeupjang consists of a mixture of meju powder (moldy soybean), water, and salt. Other ingredients can include nuruk (moldy bran), bran, wheat flour, an alcoholic beverage, maljang (dried fermented soybeans), ganjang (liquid soy sauce), malt, and takju (Korean murky wine). Jeupjang meju can be fermented in a vessel, most widely in baskets made of straw (sum and dungumi) or willow or interwoven twigs (chirung), but jars can also be used. The leaves of the paper mulberry are generally used for the mat and cover, but straw or leaves of the sumac, mulberry, or pine tree, soy, and fallen leaves are also used. Unlike other jangs, jeupjang is matured at $60^{\circ}C$ to $65^{\circ}C$, using heat emitted from the decomposition of horse dung, haystacks, or manure. Jeupjang became defunct or was transformed into jeomjang, jiraejang, mujang, paggeumjang, makjang, jipjang, and tojang. These jangs differ from jeupjang in that they use rice, malt, or hot pepper powder.

• Journal of Sericultural and Entomological Science
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• v.46 no.2
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• pp.58-64
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• 2004

The current study was performed to clarify the pupation disorder symptoms in silkworm which herbicide, molinate has been regarded as a causal origin. Molinate residues in mulberry leaves was monitored in major rearing area of silkworm; Yeacheon, Sangju and Namwon. Detected range of the molinate in mulberry leaves was 0.002 to 0.013 mg/kg and detection frequency was 30.0 to 81.8%. Molinate concentration in the air of mulberry tree growing area was $0.004\;{\mu}g/m^3$. Water diluted solution of molinate at the concentration of 1, 10, 100 mg/l gave no abnormal symptoms in silkworm irrespective of spraying to silkworm or spiking to diet. Exposing the silkworm to the air containing 250, 2,500, and $10,000\;{\mu}g/m^3$ also revealed no abnormal symptom. These results illustrated that the abnormal growth of silkworm encountered in the field was not caused by pesticide contamination.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.440-447
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• 2014

For this analysis, canopies of slender-spindle 'Hongro'/M9 apple trees were divided into 4 positions: upper, lower, exterior, and interior parts. The photosynthetic rate was highest in the external part of the upper canopy of the tree, where it was 4.5 times higher than in the internal part of the lower canopy. This difference was closely associated with differences in light penetration based on canopy position. Analysis of leaf growth characteristics showed that the leaves situated in the internal part of the canopy were larger and thinner than those in the external part of the canopy. The difference in leaf thickness was mainly due to thickness of the primary layer of palisade tissues (68.5 and $110.3{\mu}m$ for internal and external leaves, respectively). Fruit weight and quality were closely related to the extent of light penetration. Fruit weight, soluble solid content, and red skin color were higher in the fruits from the external part of the canopy. Thus, fruit maturity was delayed in the internal part of canopy. The fruit skin and wax layer were thicker in fruits from the internal canopy than in those from the external canopy. Therefore, our results indicate a need for improved light penetration in internal parts of the canopy and for split harvesting depending on maturity at different canopy positions.

• Horticultural Science & Technology
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• v.17 no.2
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• pp.148-152
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• 1999

This study was carried out to develop new cultivars of Z. serrata showing yellow fall leaf. Z. serrata which had yellow fall leaves were selected and then examined for contents of leaf anthocyanin and chlorophyll. In addition, for the progeny test, selected trees were grafted. Of 21 trees having yellow autumn leaves, three individuals, 'S-4', 'S-14', and 'J-32' were finally selected. They contained high level of anthocyanin with higher level in the leaves. Once developed, the yellow color remained till late autumn. Grafted plants of the selected strains showed high grafting efficiency and vigorous growth. Yellow foliage color were found to be maintained in the grafted trees. The tree 'S-4' was 7 m tall and 6 m in crown width, whereas 'S-14' and 'J-32' were 6 m tall and 4m in crown width. The soil pH of the survey sites ranged from 5.9 to 7.24. However, other soil characteristics did not show much difference among the sites with regard to inorganic nutrients including $N,\;P_2O_5,\,CEC,\,K^+,\,Ca^{2+}$, and $Mg.^{2+}$ 'S-4', 'S-14', and 'J-32' clonal lines developing yellow fall leaf were selected as new cultivars and propagated by grafting.