• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.311-325
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• 2023

This study was conducted to analyze the habitat suitability of the major honey trees including Kalopanax septemlobus Koidz., Prunus spp., Tilia spp., and Styrax obassia Siebold & Zucc. indigenous to mountain Gariwang and Yumeong using the machine learning approach (i.e., MaxEnt model). The AUC values of the model predictions were mostly above 0.7, and the results of the response curves showed that the environmental drivers that had effects on the habitat suitability of the major honey trees were elevation, mean annual precipitation, and mean annual temperature. These results indicate that climatic drivers along the elevation gradient are the main environmental drivers in explaining the distribution patterns of the major honey trees. In addition, the results of the response curves of Prunus spp. and Styrax obassia Siebold & Zucc. differed slightly in terms of slope and mean annual solar radiation as the main environmental drivers. The results of this study will be valuable for the establishment of honey tree forests and management plans for the natural and artificial forests in South Korea, as well as for the mapping the distribution of honey trees. Further studies at different regional levels, reflecting biotic drivers, will be needed to expand the production of honey and pollen at different strata and to produce honey annually.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.50-60
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• 2022

In this study, habitat suitability was analyzed for three major honey tree species, namely Kalopanax septemlobus, Tilia amurensis, and Styrax obassis, in the Baekdudaegan Mountains using MaxEnt models. The AUC values indicating the prediction accuracies of the models were 0.747, 0.790, and 0.755 for K. septemlobus, T. amurensis, and S. obassis, respectively. The most important variables for K. septemlobus and T. amurensis were elevation, mean annual temperature, and slope, whereas mean annual temperature, elevation, and mean annual precipitation were the most important predictors for S. obassis. For all three studied species, elevation and mean annual temperature were the most important topographic and climatic factors, respectively, indicating that such variables are crucial for explaining species distribution. Honey tree species are essential resources in forest beekeeping, a high value-added process for improving forest income, and this study identified sites with the potential for management of such species in the Baekdudaegan Mountains, where it may be possible to establish a honey forest. However, the accuracy of the models should be improved through comprehensive analysis with abiotic variables, such as soil properties and aridity, which affect the distribution of honey tree species, as well as biotic variables, such as interspecific competition.

• Korean Journal of Food Science and Technology
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• v.3 no.3
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• pp.168-171
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• 1971

Estimable taste constituents of the honey, e.g. amino acids, organic acids and sugars, were studied to evaluate the quality as well as the quantity of the honey obtained from several different origin. In the level of sugars and its components were very likely at all kinds of honey but sucrose amounts were slightly higher in feeding honey. Amino acids were highest in wild honey not only in its amount but its variety. Main components of the amino acids were found out as proline in feeding honey and in Tillaceae tree honey and as isoeucine in wild honey. Feeding honey demonstrates highest level of organic acids and the major constituents were oxalic acid and citric acid from wild honey, lactic acid from Tillaceae tree honey, and succinic acid from the feeding honey.

• Journal of Apiculture
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• v.33 no.4
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• pp.297-301
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• 2018

Hawthorn is widely distributed in Korea and has been used as herbal medicine for treating various cardiovascular disease, arteriosclerosis and hypertension in Korea. In order to select superior honey tree plant from Korea, the free sugar and organic acid in hawthorn fruits, including five Korean clones and four Chinese cultivars, were evaluated. We also compared these hawthorn fruits of five clones (selected from different area of Korea) with Chinese hawthorn cultivars. Glucose, galactose, fructose and sucrose were the major sugar components of hawthorn. In this study, we observed that sucrose, glucose and fructose content. The highest sucrose content of hawthorn fruit was 188.12g/100g in Daegeumseong cultivar. The sweetness index, which plays important role of taste, was also calculated from the content of sucrose, glucose and fructose. The contribution of each carbohydrate was calculated, based on the fact that fructose is 2.30 and sucrose 1.35 times sweeter than glucose. The highest sweetness of hawthorn fruit was 579.52 in Pocheon clone. Main organic acid detected in hawthorn fruit were citric acid, malic acid and shikimic acid. The highest citric acid and malic acid content in hawthorn fruit were 157.50g/100g (Pocheon 3) and 34.12g/100g (Daegeumseong), respectively. The results of this study would be helpful for using food and functional food products, due to the beneficial effects of free sugar and organic acid for human health such as antioxidants and anticarcinogenic properties.

• Journal of Apiculture
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• v.33 no.4
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• pp.227-237
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• 2018

The majority parasitic bee mites of Thailand in genus Tropilaelaps are infesting colonies of native bees (Apis dorsata) and introduced bees (A. mellifera). The investigation aims to study morphological and genetic variation of Tropilaelaps mites infected different hosts. Adult mites were collected from honey bee brood throughout Thailand. Traditional and geometrical morphometrics were measured on photograph by using TPS program. Additional, COI gene variations were examined by PCR-RFLP and nucleotides sequencing. Tree of mites relationships were constructed by NJ and MP assumptions. Morphometric results indicated T. mercedesae were major species infesting on A. dorsata and A. mellifera. Mophological variation represented at anal and epigynial plate, which the shape of the anal plate apex margin has been key character to identify between T. mercedesae (bell to blunt shape) and T. koenigerum (pear shape). However, the discriminant analysis suggested that geometric results were potential to classify Thai Tropilaelaps populations from different hosts better than traditional morphometric. Otherwise, PCR-RFLP clearly detected the site of Dra I and Xba I digestion of Thai Tropilaelaps morphotypes. The COI sequences of T. koenigerum were founded infesting only A. dorsata in Thailand and four sequences that related to the Thai T. mercedesae morphotypes. The NJ and MP tree were clearly classified Thai Tropilaelaps species which were suggested both from morphological and molecular analysis. This information might be basically of taxonomic status, but this should have implication for controlling these mites in Thailand and other countries.

• Journal of Korean Society of Forest Science
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• v.111 no.2
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• pp.311-318
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• 2022

We conducted this study to derive the site index, which is a criterion for the planting of Robinia pseudoacacia, a honey plant, and to investigate the diameter distribution change by derived site index. We applied the Chapman-Richards equation model to estimate the site index of the Robinia pseudoacacia stand. The site index was distributed within the range of 16-22 when the base age was 30 years. The fitness index of the site index estimation model was low, but we judged that there was no problem in the application because the residual distribution of the equation had not shifted to one side. We used the Weibull diameter distribution function to determine the diameter distribution of the Robinia pseudoacacia stand by site index. We used the mean diameter and the dominant tree height as independent variables to present the diameter distribution, and our analysis procedure was to estimate and recover the parameters of the Weibull diameter distribution function. We used the mean diameter and the dominant tree height of the Robinia pseudoacacia stand to show distribution by diameter class, and the fitness index for dbh distribution estimation was about 80.5%. As a result of schematizing the diameter distribution by site indices as a 30-year-old, we found that the higher the site index, the more the curve of the diameter distribution moved to the right. This suggests that if the plantation were to be established in a high site index stand, considering the suitable trees on the site, the growth of Robinia pseudoacacia woul d become active, and not onl y the production of wood but al so the production of honey would increase. We therefore anticipate that the site index classification table and curve of this Robinia pseudoacacia stand will become the standard for decision making in the plantation and management of this tree.

• Journal of the Korean Society of Food Culture
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• v.2 no.1
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• pp.17-24
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• 1987

As people know how to brew a wine from fruits and cereals, they continued to develope various wines good to their taste. Korean wines are also ones made from cereals and they have long been eager to improve the delicate taste. They used to drink Takju, raw rice wine, made from nonglutinous rice and Nuruk, a kind of yeast starter. During Koryo Dynasty, Soju a liquor was imported from Won(the Chinese dynasty). Nowadays this traditional folk wine, which had been developed variously and drunk all over the country, is decreasing year after year. The purpose of this study was to review on the wines ; its kinds, raw materials, brewing method, manufacturing utensils, measuring units and devices and the terms for wine making based on 20 documents published in 1600, in the middle of Yi dynesty. The results of review were as follows. 1. There were 121 kinds of wines at that time in Korea. 2. Among the raw materials for wines, major materials were glutinous rice, nonglutinous rice, wheat flour, wheat, mung bean, and black soybean. And minor materials were pepper corn, Lycium chinenisis, cinnamon, pine needles, pine nuts, jujube, mugwort leaves, lotus leaves, pine corn, pine bud, chrysanthemum, pine flowers, honey, Acanthopanox seoultenses, bamboo-root, marrowbone of blak cow, sweet flag, Ciprus noblis, Saurea lappa, honey suckle, Tricho santhes, azalea, the leaves of the paper mulberry, and bark of chungum tree. 3. There were several kinds of wines such as a wine without using Nuruk, a wine made from glutinous rice, nonglutinous rice, or glutinous and nonglutinous rice with flour. 4. There were several brewing methods for wines such as a wine boiled with ring rice cake, a wine brewed with loaves of rice cake, a wine brewed with hard boiled rice, a wine brewed with rice gruel, and a wine brewed with powdered rice gruel. 5. There were 23 kinds of utensils including measuring devices for weight and volume.

• Journal of Korean Society of Forest Science
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• v.109 no.4
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• pp.512-520
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• 2020

We assessed the nectar source potential of a prospective honey plant, Idesia polycarpa, by analyzing nectar volume, free sugar content, and free amino acid content. Idesia polycarpa is a dioecious tree; the males bloom approximately four days earlier than females, and the blooming period is approximately 17 days-from March 14th to March 30th. Upon investigating the patterns of nectar secretion, it was found that male flowers peak on the third day of blooming at 5.0 ± 2.5 μL, and female flowers peak on the second day of blooming, at 1.1 ± 0.4 μL. There was a significant difference between males and females in the total nectar volume (9.7 ± 2.9 μL for males and 1.7 ± 0.5 μL for females) and the dried nectar volume (2.2 ± 0.6 μL for males, 0.8 ± 0.3 μL for females) during the blooming period. The free sugar content of floral nectar was 54.6 ± 15.4 ㎍/μL for males and 20.5 ± 4.9 ㎍/μL for females, and the sugar content per flower was higher in males (170.7 ± 15.4 ㎍) than in females (24.9 ± 5.5 ㎍). Our analysis of the amino acid content showed that 20.4 ± 3.9 mg/L (comprised of 19 amino acids) is produced in male flowers and 3.2 ± 0.1 mg/L (11 amino acids) in female flowers. In the male flower, the main amino acid was glutamine, followed by asparagine and proline, whereas in the female nectar, asparagine was the main amino acid, followed by glutamic acid and glutamine. Idesia polycarpa blooms after the blooming period of a major honey plant, Robinia pseudoacacia, and its nectar volume and nectar characteristics, such as free sugar content and amino acid content, make it a viable honey plant.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.427-435
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• 2023

Changes in flowering time due to weather fluctuations impact plant growth and ecosystem dynamics. Accurate prediction of flowering timing is crucial for effective forest ecosystem management. This study uses a process-based model to predict flowering timing in 2023 for five major tree species in Korean forests. Models are developed based on nine years (2009-2017) of flowering data for Abeliophyllum distichum, Robinia pseudoacacia, Rhododendron schlippenbachii, Rhododendron yedoense f. poukhanense, and Sorbus commixta, distributed across 28 regions in the country, including mountains. Weather data from the Automatic Mountain Meteorology Observation System (AMOS) and the Korea Meteorological Administration (KMA) are utilized as inputs for the models. The Single Triangle Degree Days (STDD) and Growing Degree Days (GDD) models, known for their superior performance, are employed to predict flowering dates. Daily temperature readings at a 1 km spatial resolution are obtained by merging AMOS and KMA data. To improve prediction accuracy nationwide, random forest machine learning is used to generate region-specific correction coefficients. Applying these coefficients results in minimal prediction errors, particularly for Abeliophyllum distichum, Robinia pseudoacacia, and Rhododendron schlippenbachii, with root mean square errors (RMSEs) of 1.2, 0.6, and 1.2 days, respectively. Model performance is evaluated using ten random sampling tests per species, selecting the model with the highest R². The models with applied correction coefficients achieve R² values ranging from 0.07 to 0.7, except for Sorbus commixta, and exhibit a final explanatory power of 0.75-0.9. This study provides valuable insights into seasonal changes in plant phenology, aiding in identifying honey harvesting seasons affected by abnormal weather conditions, such as those of Robinia pseudoacacia. Detailed information on flowering timing for various plant species and regions enhances understanding of the climate-plant phenology relationship.