• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.1
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• pp.1-12
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• 2022

Tilia amurensis is an important honey plant. As T. amurensis mainly distributes mountainous area with various elevations in Korea, accurate prediction of blooming time at the different elevation would benefit forest beekeepers. In this study, we measured time-dependent blooming progress of T. amurensis in Mt. Gariwang area ranging from 500-1500m. Additionally we collected blooming data from web and published literatures and estimated the variation of blooming time relative to the geographic locations. Flowers began to bloom from July 6 to July 22 with full blooming on July 14 in location where elevation is 638m in Mt. G ariwang area in 2021. Based on these databases, a growing degree day (G DD) model was developed for prediction of T. amurensis blooming progress using average daily temperatures. Using the starting date of G DD accumulation of January 1 and base temperature of 5 ℃, blooming period ranging from 10% to 90% of cumulative blooming rate was estimated as 860-1198 degree days (DD). This corresponded to the beginning to the end of July in Mt. Gariwaning area in 2021. This model could explain the phenological variations of T. amurensis flower blooming possibly affected by elevation within geographic area, latitude or year relative to the climate change, and aid forest beekeepers for better timing of nectar foraging by honey bees.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.1 no.1
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• pp.36-41
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• 1963

10 of Korean domestic recommended varieties(all of them are determinate type) and 10 of introduced varieties from U.S.A.(All of them are indeterminate type) are grown in replicated field in order to clarify the varietal differences in the days from planting to blooming to ripening. The results are summarized as follows; 1. Domestic varieties showed remarkable shortday sensibility for the days from planting to blooming. The difference in sensibility between domestic and introduced was significant while within the domestic group the differences were not significant. 2. The days from planting to blooming were linearly shortened in accordance with the delayed planting from the late April through the late June. 3. Annual variation in days from planting to blooming was not noticeable in the domestic varieties while the introduced ones showed remarkably. 4. The days from blooming to ripening were significantly shortened for the introduced varieties but not significantly for the domestic varieties accordingly with the delayed planting. The mean shortest days of domestic varieties were longer than the mean shortest days of introduced varieties. 5. The days from planting to blooming was shortest when a variety was grown during early August through middle September (with 12.5~13.5 hrs day length and 22~$27^{\circ}C$ temperature), and the days from blooming to ripening were also shortest when a variety was matured within same duration. These were true for the varieties of both groups.

• Journal of Korean Society on Water Environment
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• v.31 no.5
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• pp.533-542
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• 2015

In order to investigate the effect of internal loading from sediment on algal blooming at Chusori area in Daechung Reservoir, the amount and contamination level of sediment and the release rate of total phosphorus were analyzed. The sedimentary layer was consisted with two layers, and the average depth of upper and lower ones were 0.35 and 1.44 m, respectively. The fraction of inorganic phosphorus in the sediment was higher than that of organic phosphorus, and the fractions of phosphorus which responsible for internal loading were very high as in the range of 72.7 and 80.2% of inorganic phosphorus. The C/N ratio of sediment taken with core sampler indicated the organic compounds are originated from settled algae from water body. The average release rate of total phosphorus from sediment was $6.74({\pm}0.50)mg/m^2/day$. These results indicated that the internal loading from sediment contributes the excessive algal growth at Churosi area, and the countermeasures to improve the quality of sediments are required to manage algal blooming in Daechung Reservoir.

• Food Science and Preservation
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• v.1 no.1
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• pp.45-53
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• 1994

Circulation state and changes in quality during ripening of strawberry were investigated. Tissue damage of the fruit happened when it was harvested and selected. Strawberry has been harvested without considering of fruit temperature in the farm. It takes 25 hours from Goreung which is main production area of strawberry to retailer, and seasonal variation in the price was severe. Shelf-life of strawberry from Feb to Mar was 5-6 days, and was 24-30 hours from May to June. Desirable ripening stage was 28-30th day after blooming and 40th day and after this was over ripening stage when the degree of ripening estimated by color "a" value and color saturation. Overall eating quality and vitamin C contents and sugar content were more higher in the fruit of the desirable ripening stage than that of unripening and over ripening stage. The dark redness degree was high in the over ripening stage.

• 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.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.5
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• pp.59-69
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• 2013

Global warming also has effects on the phenology. The limitation of phenology study is an acquisition of phenology data. Satellite images analysis can make up limitation of monitering data. This study is to analyze spatial distribution and characteristics of phenology changes using MODIS images. Research data collected images of 16 day intervals of 11 years from year 2001 to 2010. The data analyzed 228 images of 11 years. It can figure out changes of phenology by analyzing enhanced vegetation index of MODIS image. We made a comparison between changes of phenology and flowering of cherry blossoms. As a results, Startup of season spatially was getting late from southern area to north area. Startup of Phenology was foreshortened 13 days during 11 years, and change ratios of cherry blooming was getting more faster from 0.18 dat to 0.22 day per year during that same period.

• Journal of Microbiology
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• v.34 no.4
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• pp.300-304
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• 1996

To define the effects of zooplankton and phytoplankton to bacteria, bacterial numbers, frequency of dividing cells (FDC) and size distribution were performed with image analysis in the surface layer of Lake Soyang. In August 1992, when Anabaena was blooming, the bacterial number increased at daytime. Bacterial numbers and FDC value had a negative correlation (r = 0.83, P < 0.01). Bacterial size spectrums were dynamically changed during the day and night, especially the small bacteria less than $0.5\;{\mu}m^3$. Meanwhile, in October, after the bloom, the bacterial number was only one third of that in August, even though the FDC was higher than that in August. The bacterial numbers of small size class dropped at 13:00. But the size spectrums were relatively constant during the night time. These results suggest that the bacterial growth was tightly coupled with phytoplankton during Anabaena bloom. And after the bloom, the bacterial number was controlled grazing activity of zooplankton at daytime.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.5
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• pp.578-584
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• 2006

This research analyzed the contents of ascorbic acid according to cultivating season, regions and cooking method. The ascorbic acid content was steadily increased from 40.08 mg per 100 g on the 5th days after blooming to 90 mg on the 30th day, an increase of 2.25-fold. The ascorbic acid content of the peppers was highest for (C) region at 100.9 mg per 100 g, followed by (B) region at 90 mg and (A), region at 23.35 mg. it increased by ascending downward from the stem. If examining species' and regional ascorbic acid change of marketing peppers, it was contained in flesh most and placenta, seed in order in four species. The ascorbic acid content of the peppers was affected by the cooking method and decreased greatly in the order of blank>microwave>$saut{\acute{e}}ing$> boiling> steaming.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.3
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• pp.243-250
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• 1981

Soybean, azuki-bean and mungbean were cultivated at different growing conditions, May 10, June 9, July 9 seeding, and May 10 seeding-short day treatment, to investigate the distribution of flowering date and the variation of pod/flower ratio. The growth habit type of the soybean variety used was determinate, but the azuki-bean and mungbean varieties used showed indeterminate growth habit. The pod/flower ratio ranged 38 to 48% for soybean, 23 to 34% for azuki-bean and 46 to 60% for mungbean along with growing conditions. Flower abscission for soybean and mungbean, and pod abscission for azuki-bean affected more on the number of matured pods. Soybean showed once full blooming period, but azuki-bean and mungbean showed two or three times full blooming period except July 9 seeding plot through the whole growing period. Flowers bloomed just after every full blooming period showed lower value of pod/flower ratio and higher pod/flower ratio was obtained from flowers bloomed before or far after full blooming at plots seeded May 10 and June 9 in three pulse crops. Most full blooming period of soybean coincided within 5 days near the terminal leaf appearance date, and number of flowers bloomed before terminal leaf expansion and matured pods from these flowers were major in every soybean plant at all growing codition plots. No relations were found between terminal leaf appearance and flowering or pod setting patterns of azuki-bean and mungbean.

• Fisheries and Aquatic Sciences
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• v.21 no.4
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• pp.9.1-9.7
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• 2018

To establish a comprehensive management strategy, as part of the optimization of cultural practice for an oyster rack culture system, we used a numerical model to estimate the primary production in the waters on the eastern coast of Wando island, South Korea. The estimated primary production ranged from 17.12 to $1052.55mgC\;m^{-2}day^{-1}$ ($204.22{\pm}224.75mgC\;m^{-2}day^{-1}$ in average). Except for the times of peak phytoplankton blooms, the estimated primary production (PP) was consistently under $200mgC\;m^{-2}day^{-1}$, which is more similar to the value of PP measured off the western coast of South Korea than the southern coast. No clear relationship was observed between nitrogen content and rainfall with the exception of heavy rainfall events, indicating that precipitation might not be the main source of nutrients in these waters. No clear influence was observed from Doam tidal discharge, located 24 km north from these waters due to main tide comes in this area from the channel between Gunwe-myeon in Wando island and Pukpyeong-myeon in Haenam-gun. Because of the shallow water depth and strong tidal current, resuspension of sediments, which causes an input of nitrogen into the system, could be easily caused by even mild wind and the infrequent passing of ships. Microscopic examination of the phytoplankton composition showed additional contribution of benthic species such as Paralia sulcata into the waters, which increase the productivity of oyster farms in the waters. The availability of nitrate and phosphate for primary production was temporarily limited throughout most of the spring and autumn blooming season.