• Korean journal of applied entomology
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• v.58 no.3
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• pp.219-224
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• 2019

The super mealworm, Zophobas morio, is mainly used as food for pets, fish, reptiles, amphibians, birds, and as snacks. An experiment was conducted to investigate the effects of temperature, supplementary feeding, and spawning interval on super mealworm rearing. To efficiently rear this species, the insects were bred at a temperature of $27^{\circ}C$ or higher and reached a weight of over 0.6 g at 80 days after hatching. Supplementary feed (with high protein content: 10% of soybean meal and 10% of fish meal) enabled larvae to reach a weight of over 0.7 g at 80 days after hatching. Mass rearing of super mealworm requires increase in egg production (i.e., high yield) and uniformity of larvae. Adults were transferred to spawning bases every 5, 10, or 15 days (three treatments), which resulted in a total of 7,256, 5,439, 2,060 hatched larvae, respectively. It is possible to obtain more than 7,000 larvae by transferring the egg-laying frame to the spawning base at intervals of 5 days and with nine spawning operations; this procedure generates larvae weighing over 0.68 g each.

• Korean Journal of Environment and Ecology
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• v.32 no.6
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• pp.575-581
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• 2018

The relationship between the body size of species and the environment has been an active research subject for many years. Until recently, studies had focused on the relationship between the body size and environment based on the ecogeographic rule for various animal groups. In this study, we examined the relationship between body size of Hyla japonica and the habitat environment in Jeju island located at the southernmost part of the Korean peninsula. We collected H. japonica from three breeding sites, Cheonji, Bonggae, and Aewol, and measured SVL, BW, and HW of the species. We also measured the altitude, longitude, latitude, annual mean temperature, and annual mean precipitation of each site to analyze the relationship between the body size and the habitat environment. The analysis results showed that there was the clear difference of the body size according to the habitat and the body size in Aewol was significantly bigger than others, while the body size in Cheonji was the smallest. The altitude was the most important environmental variable and showed a positive correlation with body size. The body size of H. japonica increased as the altitude increased, and this results were consistent with Bergmann's rule, one of the biological laws related to body size. In conclusion, the environment could affect the body size of H. japonica, and the body size has a certain direction according to the environment.

• Journal of agriculture & life science
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• v.52 no.6
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• pp.1-12
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• 2018

This study was conducted to analyze the openness of erosion control dams situated near mountain stream. The ecological functions of erosion control dams analyzed by such openness for adequately protect and manage the diversity of species and to prevent disasters. The obtained results were as follows. When structurally modifying or changing non-permeable, gravity type dams with a passing rate of less than 1% into open-type dams, the passing rate increased by about 77 times more from 0.72% to 55.8%. Except for closed, gravity type erosion control dams that are constructed with a special purpose such as creating sand deposits and reservoirs, there is a need to construct and improve the dams into permeable type dams that can relatively satisfactorily perform various functions such as carrying soil and sand to the downstream region and create a ecological corridor upstream and downstream for fish and amphibians. The openness based on the blocking height of the erosion control dam varies depending upon the height of the base part and the depth of the substructural part. It must be designed based on the on-site conditions and the purpose of the construction. The functional types of erosion control dams based on the open form of the cross-section as follows: the fish traffic type, flood control type, reservoir type for forest fire control), non-permeability type for soil and rock blocking, net type for blocking the rock flow and the particle screen type.

• Korean Journal of Heritage: History & Science
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• v.44 no.1
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• pp.122-137
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• 2011

The purpose of this study was to present the characteristics of tree growth and the status of the ecosystem in Yeongdeok Docheon-ri Docheon forest, which was designated as Natural Monument No. 514. Results showed that most of the soil properties were generally within desirable levels except for some properties. The forest was composed of 503 trees. Major trees included Zelkova serrata, Celtis sinensis, Cornus walteri, Diospyros lotus, Hemiptelea davidii, and Evodia daniellii. In particular, trees such as Zelkova serrata, Celtis sinensis, and Cornus walteri showed D.B.H ranging from 10cm to 70cm. These trees appeared to be major tree species since the beginning of Docheon forest's existence. The wild birds observed from the site were from 18 families, 20 species, and 95 individuals. Also were found 1 mammal species, 1 reptile species, and 1 amphibian species. A dead Aix galericulata (designated Natural Monument No. 327) was found in the forest. The annual tree diameter growth of the sample trees was 2.3mm per year on average. The average age of the overstory trees was approximately 101 years, and the oldest tree was estimated to be 300~400 years old.

• Journal of Environmental Impact Assessment
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• v.31 no.1
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• pp.75-81
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• 2022

The purpose of this study is to propose the angle-limit of the escape ramp by analyzing the frog behavior characteristics according to the inclination angle of the waterway escape ramp installed in the concrete U-bench plume pipe channel. Forthe experiment, an escape test device was manufactured with the same shape and number of materials applied in the field. And Rana coreana living in paddy wetlands were sel selected. The main behaviors of frogs on the slope were 'jumping', 'crawling' and 'slipping', and afterrecording the behavioralresults according to the inclination angle, statistical analysis was conducted using the chi-square test method. As a result of the analysis, there was no statistically significant difference between 30° and 40°. This result is an evidence for expanding the standard of inclination angle 30° suggested in the 'Guidelines for Installation and Management of Ecological Pathways' to a maximum of 40°. However, further research is required in that the escape ramp targets not only Korean frogs but also various small wild animals. However, considering that various wild animals are affected by artificial canals, additional studies using various target wild animals are needed.

• The Korean Journal of Zoology
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• v.19 no.1
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• pp.25-32
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• 1976

To observe the changes of mucosubstances of the mucous secreting cells, stomach tissues in frog tadpoles at each stage of metamorphosis were fixed in 10% buffered formalin at $4^{\circ}C$, embedded in paraffin, sectioned to 4 $\mu$m thickness and stained with periodic acid-Schiff(PAS) and alcian blue (AB) of pH 2.5 and pH 1.0. The results obtained were as follows: 1. The reactivities of the surface mucous cells, which exhibited strong PAS-positivity and weak alcianophilia at both pH 2.5 and 1.0, were not changed in metamorphosis stages and the intracellular contents of neutral mucosubstances in the surface mucous cells increased significantly in XXIV and XXV stages of metamorphosis. 2. In the foveolar mucous cells, which appear after metamorphosis XXI, the staining reactivities to PAS, AB of pH 2.5 and 1.0 were the same as that of surface mucous cells during metamorphosis and the alcianophilia were stronger at pH 1.0 than at pH 2.5. 3. THe mucous neck cells, which appear after metamorphosis XXIV, exhibited a strong PAS-positive reaction and weak alcianophilia at metamorphosis XXIV but at metamorphosis XXV weak reactivity to PAS and strong alcianophilia at pH 1.0.

• Journal of Wetlands Research
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• v.26 no.2
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• pp.160-167
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• 2024

The amphibians serve as environmental indicator species warning of threats from pollution and development, and information regarding their body condition and surrounding habitat can be utilized as crucial indicators for assessing ecosystem health. The objective of this study was to investigate the differences in body condition and the climate environments according to the season and sex of Class II endangered Kaloula borealis. A total of 53 surveys were conducted from June to October 2018, targeting frogs inhabiting the Godeok-dong area of Gangdong-gu, Seoul. Using the weight and length of each individual, the body condition index (SMI, Scaled mass index) was calculated. Results showed a total capture of 396 individuals, consisting of 235 males and 161 females. Females exhibited longer SVL and greater weight compared to males, with higher body condition indices. Monthly body condition indices were lower for males in June, while no differences were observed between males and females from July to September. Among the climate environments where females and males appeared, environmental variables related to precipitation and humidity showed differences. These research findings are deemed crucial for providing fundamental information to ascertain suitable habitats for Kaloula borealis and selecting alternative habitats due to developmental impacts in the future.

• Journal of the Korean Society for Nondestructive Testing
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• v.30 no.4
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• pp.386-395
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• 2010

The steam generator management program(SGMP) has recently defined the procedures for the qualification of eddy current hardware and technique. These procedures provide two basic methods for qualification. The first way is to qualify the equipment or the probe by using the flaw mechanism and method of the pulled tubes from the heat exchangers or the artificial flawed tubes. The second way is to verify the equivalency with the characteristics of the qualified equipment or probe. In this case, the qualified equipment or probe may be modified to substitute or replace instruments or probes without re-qualification provided that the range of essential variables defined in the examination technique specification sheet are met. This study is to describe the result of the comparative performance evaluation of bobbin coil eddy current probes manufactured by KEPCO Research Institute and probes manufactured by a foreign manufacturer. As a result of this study, although there were minor differences between the two kinds of probes, it was evaluated that the two kinds of probes were almost identical in the significant performance characteristics described in the KEPCO Research Institute guideline.

• The Korean Journal of Zoology
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• v.27 no.3
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• pp.127-136
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• 1984

The specification of dorsal/ventral axis in the egg of Xenopus laevis was investigated as a series of oblique orientation to gravity by tilt and clinostat. The results are as follows. (1) If the eggs were oriented, in the early period after fertilization, to novel gravity by $15^\\circ, 30^\\circ, 45^\\circ$ and $60^\\circ$ tilt until gastrula stage, the site of involution was usually formed in the OpG side (the side opposing gravity). As the degree of tilt was raised from $15^\\circ to 60^\\circ$, the rate of relocation of the involution site was proportionally increased. (2) When UV-irradiated eggs were tilted period to first cleavage by $15^\\circ, 30^\\circ, 45^\\circ$ and $6\^\\circ$, the effect of UV syndrome was rescued, and the extent of rescue was propotional to the tilt degree. (3) The fertile eggs were loaded on the clinostats of several speeds. In the range of low speeds between $0.45 \\sim 9.0$ rph, the location of dorsal lip was dependent on the direction of rotation, and in $40 \\sim 360$ rph, lip was formed at a random position. In addition, some of the tadpoles experienced with clinostat showed the typical syndrome of "dorsal axis reduction". The above results were discussed regarding the mechanism of the establishment of dorsal/ventral palarity. palarity.

• Korean Journal of Environmental Biology
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• v.21 no.1
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• pp.45-51
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• 2003

Genetic diversity of local populations among geologically isolated groups of Rana amurensis was refined by sequence comparison of the mitochondrial (mt) 165 rDNA genes. Each 401 base pairs of DNA sequences, which was determined from four local populations of Rana amurensis, two local populations of R. nigromacutata, and three species of the genus Rana were used in this analysis. Despite morphological similarity of Rana amurensis, Korean populations were well distinguished from the other groups on the basis of 105 rDNA gene difference. Further analyses for additional local populations belonging to R. amurensis will be necessary to clarify the taxonomic status.