• Korean Journal of Soil Science and Fertilizer
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• v.24 no.3
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• pp.165-170
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• 1991

Effects of liming and starch application on the soil pH and mineralization of organic nitrogen were compared to control at $30+/10^{\circ}C$ incubation for six weeks in two soil types(loam, sandy loam) adjusted with 80% of field moisture capacity. 1. While soil pH was increased abruptyl one week after incubation in loam applied with lime and lime+starch, it tended to decrease at control during incubation period. Liming on sandy loam increased soil pH, and application of lime+starch together showed high pH at first week of incubation which was lowered slowly after wards. Significant changes in soil pH was not detected at control or starch application only. 2. The content of $NH_3-N$ in loam started to increse three weeks after incubation, and was maximized at fifth week. Positive correlation was shown at control during incubation period between soil pH and $NO_3-N$ content. Level of $NO_3-N$ content applied with starch or lime+starch was low compared to control. 3. The $NH_4-N$ content was high when sandy loam was applied with lime+starch together. At the first week of incubation, the $NO_3-N$ content was high at control or lime application.

• Korean Journal of Ornithology
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• v.25 no.2
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• pp.69-76
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• 2018

Sexual dimorphism in birds refers to male-female differences in body size, plumage, color and/or behavior. In general, many seabirds, including the family of Laridae, are monomorphic in plumage-color, which makes the determination of sex difficult in the field because both parents also tend to share a great portion of parental care. The development of an inexpensive sexing tool facilitates understanding the degree of sex-specific parental care in the evolution of the life history. Here, we developed a non-invasive method for the determination of sex using the bill-head morphometric of known captive pairs and applied this tool to wild pairs to document factors underlying male-female parental care during the incubation period of Saunders's gulls (Saundersilarus saundersi). Males exhibited relatively larger bill-head ratios than their mates within naturally formed pairs in captivity, resulting in the determination of sex in12 wild pairs at the nest during the incubation period. Males and females equally shared the incubation role during the daytime, attending the nest at a high rate of 95%. However, the male's proportion of nest attentiveness greatly increased with time towards sunset, presumably reflecting the male duty for nighttime incubation. The present study provides a non-invasive method for the determination of sex in a monomorphic seagull species and highlights how male-female incubation behavior is associated with time of the day, rather than other ecological conditions.

• Korean Journal of Environment and Ecology
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• v.28 no.2
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• pp.105-112
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• 2014

During incubation, pelagic seabirds undergo large variations in their body mass as a result of concomitant fasting. In Procellariifomes undergoing important changes in body mass through the incubation, body mass regulation could be an important factor in behavioural decisions for changing activities during the incubation. The aim of this study was to investigate the effect of individuals' quality and incubation behaviour on their body mass regulation in Streaked Shearwaters Calonectris leucomelas breeding at Sasudo Island, in Jeju, South Korea during incubation period, June to August in 2013. In our results, we found that there was no relationship between the daily body mass loss and body size or condition of Streaked Shearwaters. However, the daily body mass loss increased significantly as the incubation bout increased. Moreover, the daily incubation bout was positively related to their body size. Consequently, although breeders' qualities were not related to their daily body mass loss during the incubation, the incubation behaviour affecting their daily body mass loss was regulated by their body size. Therefore, the body size of Streaked Shearwater breeders is one of important factors in their decisions for the incubation behaviour.

• The Korean Journal of Ecology
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• v.8 no.2
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• pp.119-126
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• 1985

One nest of the Common Kingfisher Alcedo atthis bengalensis Gmelin breeding in the area of Mt. Bangu, Mugye-ri, Jangye-ri, Jangyu-myon, Gimhae-gun, Gyongnam province, was observed for 43 days from July 18 to August 29, 1984. The nest was found at a height of 71cm in a steep mountain side. It was tunnel-shaped, with a size of 53cm(length), 5.5*6.4cm (the diameter of entrance) and 16.1*10.5cm (the diameter of incubation seat). The cluth size was 5 eggs. The eggs were white in color, the average size of 5 eggs being 20mm (length)*17.9mm(width). The incubation period was 18 days, the parent birds stayed in the nest at on average of 494 minutes and the rate of incubation was 82.20%. The incubation time increased gradually. The nesting period of 3 chicks was 25 days, and the average feeding frequency was 5, 50 times per day with the highest frequency of 10 times on the 14th days after hatching. The time and frequency of attendance gradually decreased as their chicks grew up. Total increase length in body was; body length 45.35longrightarrow147.80mm, wing 6.95longrightarrow63.40mm, bill 1.73longrightarrow29.36mm and body weight 2.93longrightarrow41.00gr. The prey for the 3 chicks of the nest was entirely fish. The main food item was the fry of Gobiobotidae. The home range of the nest was 0.43ha. and the territory size was 0.05ha. Their feeding ground were outside of their territory.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.2
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• pp.63-70
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• 2001

Changes in concentrations of dissolved oxygen, ammonia, nitrate, pH, Fe and Mn were monitored from the laboratory incubation of an benthic chamber. The extent of sedimentary organic carbon and nitrogen decomposition was quantified by applying the concentration data to the chemical reaction equations of early diagenesis. The patterns of the concentration changes, observed during the 237 hr long incubation experiment, made it possible to divide the entire experiment period into four characteristic sub-periods (0-9 hr, 9-45 hr, 45-141hr, 141-237 hr). C/N ratio, estimated for each sub-period, was 6.63, 1.49, 0.81 and 0.02, respectively. This sequential decrease in C/N ratio suggests that during the incubation experiment dissolved nitrogen species diffuse more out of the sediment than dissolved carbon species. Greater diffusion of nitrogen indicates the preferential decomposition of organic nitrogen during early diagenesis of sedimentary organic matter. Comparison of the concentration data (sedimentary organic carbon and nitrogen, porewater organic carbon and ammonia)between the sediment pre and post incubation also indicates the preferential decomposition of nitrogen during early diagenesis of sedimentary organic matter.

• 한국균학회소식:학술대회논문집
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• 2018.05a
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• pp.29-29
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• 2018

Sparassis latifolia is called "Cauliflower Mushroom" and is known as an edible mushroom that has high content of ${\beta}$-glucan. Recently, artificial cultivation of S. latifolia has been done by bottle, plastic bag and wood cultivation in Korea. However it is not widely used because there are low incubation ratio and yield. For the high efficiency of production, we aim to find the superior strains and media for better mycelial and fruit body growth. First, we analyzed the genetic relationship among 31 strains and divided five groups with three kinds of URP primers. And then ten strains were selected from five groups based on the experiment of mycelial growth. The suitability of media for mycelial growth was different according to media type. The suitable solid and liquid media for mycelial growth of S. latifolia isolates were PDA and M2, respectively. In addition, with regard to C/N ratio, the mycelial growth increased even until C/N 160. Second, we investigated the production of fruitbody of the strains by plastic bag cultivation. The substrate was mixed with larch sawdust, corn flour, and wheat flour (8:1:1, v/v). Moisture content of substrate was controlled by about 60% with 10% molasses solution. Out of 31 strains, 19 strains formed primordia. The eight strains produced more than 140g/1kg in fresh weight. Third, molasses culture media was selected for the mycelial growth. And molasses suitable sugar content and input aeration were around 8Brix% and 0.3~0.6vvm, respectively. The longer the incubation period is, the more dried weight of mycelia increased, but medium volume decreased. Therefore, the best incubation period was 9 to 11 days depending on strains. In the future, research project entitled development of culture system and new variety for stable production of S. latifolia will be considered as a new item.

• The Korean Journal of Ecology
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• v.25 no.4
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• pp.241-245
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• 2002

During the breeding season of 1998, breeding ecology of the Great Reed-Warbler (Acrocephalus arundinaceus orientalis) was studied at Yangsoo-ri and Yongdam-ri of the Yangpyung-gun, Kyunggi province, Korea. Egg-weight (CV: 6.25) was more variable than either length or breadth, and breadth was the least variable of the measures. Significant variations in overall egg-weight occurred between clutches, and that more of the total variation in egg-weight and shape are due to inter-clutch variation as to intra-clutch variation when the data were pooled. The last egg tends to be larger than the remaining eggs in the clutch of the Great Reed-Warbler, suggesting the Great Reed-Warbler may adopt the brood-survival strategy. When method 3 was used, the most common incubation period is 12 days. In the Great Reed-Warbler, the length of the incubation period was related to clutch-size when method 1 (r=0.485, p<0.05) and method 2 (r=0.621, p<0.01) were employed, but not related to egg weight. The averagee number of days of hatching asynchrony was 2.5, raging 0.5~2.5. Asynchronous hatching was related to the clutch size (r=0.66, p<0.01). Hatching sequence was closely related to the laying sequence (r=0.93, p<0.001), suggesting Great Reed-Warblers incubate their eggs before clutch completion. The effect of egg weight on hatching asynchrony was found in Great Reed-Warblers (t-test, p<0.01).

• Korean Journal of Environment and Ecology
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• v.38 no.2
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• pp.143-147
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• 2024

This study aimed to determine the egg-hatching period of boreal digging frogs, Kaloula borealis, and investigate whether the incubation temperature affects the hatching period. In this study, the egg hatching was recorded based on the appearance of the tadpole. The results of this study showed that all the eggs hatched within 48 hours after spawning, with 28.1% (±10.8, n=52) hatching within 24 hours and 99.9% (±0.23, n=49) within 48 hours after spawning. The mean hatching rate of tadpoles showed significant differences depending on the difference in water temperature. The mean hatching rate between 15 and 24 hours after spawning was higher at a water temperature of 21.1 (±0.2) ℃ than at 24.1 (±0.2) ℃. The results suggest rapid hatching occurs at relatively low water temperatures because the spawning habits that spawn eggs in temporary ponds or puddles in the rainy season require rapid hatching before the puddles dry out. The results of this study are helpful for understanding the most suitable temperature conditions for the incubation of eggs of the endangered species, boreal digging frog.

• Archives of Pharmacal Research
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• v.13 no.1
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• pp.33-37
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• 1990

The effects of pH values, temperature and some elements on the amylolytic activity and stability of the purified S. aureofacienc 77 amylase were studied in this investigation. The purified enzyme showed its maximum activity at pH 6 within 8 min incubation at $40^{\circ}C$. None of the tested 6 metals showed on stimulatory effect on the enzymatic activity, $Fe^{+++}$, $Cu^{++}$ and $Hg^{++}$ at high dose inhibited the enzyme activity to great extent as compared with $Zn^{++}$, $Mn^{++}$ and $Fe^{++}$ whih gave less effect in this respect. The enzyme liquor was found to be thermolabile, since it lost completely its activity after 4 days incubation under room temperature and showed maximum activity during this period as a result of additions of $Ca^{++}$and NaCl, Gradual reduction was however recorded until activity reached 30% after 60 days of incubation.

• Journal of Mushroom
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• v.17 no.3
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• pp.99-106
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• 2019

To improve the productivity of shiitake mushroom (Lentinula edodes), seven different types of media for liquid spawn (denoted as "A" to "G") were prepared with 0.3% soybean meal and varying sugar and glucose concentrations. During 14 days of incubation, the pH of the liquid culture gradually acidified with increasing incubation period. Additionally, there was a significant, but not prominent, difference in the degree of acidification depending on the sugar to glucose ratio. Liquid spawn culture "G," which had the highest sugar content was the most acidic on the last day of incubation. Mycelium dry weight increased significantly with increasing incubation period, and there was no significant difference in mycelium dry weight irrespective of the sugar to glucose ratio even after 14 days of culture. The inoculation of liquid spawn in sawdust medium with an inoculation volume ${\geq}45mL$ and incubation period of 15 to 18 days were the optimal culture conditions. Productivity of fruit bodies in sawdust medium and mushrooms treated with liquid spawn was significantly higher compared to solid spawn treatment. The mushrooms treated with liquid spawn had better chewiness, and the free amino acid content, which is associated with savory taste, was higher in these mushrooms compared to those treated with solid spawn.