• Journal of Forest and Environmental Science
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• v.28 no.4
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• pp.220-226
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• 2012

An assessment of Marsh crocodile's (Crocodylus palustris LESSON, 1831) habitat, its feasibility in supporting the total population, feeding, hatching difficulty and variations in egg and clutch size of Marsh crocodile were carried out in Bangabandhu Sheikh Mujib Safari Park for one year (July 2010 to June 2011). Major problem identified was the breeding failure, i.e. till now no hatching were found. Mainly two local weather variables (average temperature and humidity) were identified as the most obstructing parameters. Higher temperature (average $37.03^{\circ}C$) and Lower Humidity (average 75.33%) in comparison with standard range of incubation temperature and humidity for Marsh crocodile were seems to be vital reason for the failure of hatching. Understanding of the identified problem of this paper can direct the wildlife conservationist and the policy maker to take proper action for conserving the Marsh Crocodile in Bangladesh.

• Journal of Mechanical Science and Technology
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• v.18 no.12
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• pp.2265-2272
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• 2004

The aquaculture tank is used for breeding fish in sea water which was pumped up to land. The flow characteristics in the aquaculture were investigated with varying the tank geometry and flow rate. The numerical analysis has been employed for calculating the velocity and temperature distributions in a water tank of rectangular type. The finite volume method and SIMPLE algorithm with 3-dimensional standard $\kappa$-$\varepsilon$ turbulence model were used for the numerical analysis. For comparison with experimental results, the PIV system was applied to visualize the flow patterns quantitatively. The numerical results showed good agreements with the experimental results. The mean velocity and temperature versus aquarium depth were represented for various circulating flow rates. Especially, the aquaculture environment is recommended that the aquarium depth has to be d=0.5 m, and this case is the condition of higher velocity and temperature in winter season.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.726-732
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• 2004

In this manuscript, a review of the diversity of Chinese indigenous goat breeds according to data from body stature and appearance, chromosome group, blood proteins, DNA molecular markers (mitochondria DNA, random amplified polymorphic DNA, microsatellite DNA, major histocompatibility complex) has been introduced. All of these provide efficient tools for the diversity analysis of Chinese indigenous goat breeds and are very important for biodiversity conservation, restoration of declining goat breeds, the priority defining in Chinese indigenous goat breeds' protection and the selection of nature preservation zones. Many Chinese indigenous goat breeds with small population size in the isolated mountains or reservoir areas are verging the potential threat of extinction, effectively lost with the rapid destroying of ecological environment. On the other hand, as a result of the introduction of modern commercial goat breeds and shortage of effective conservation, some populations, such as Small-xiang goat and Tibetan goat decrease rapidly in number of sires. In the interests of the long-term future of the goat breeds in China, conservation of goat breeds' genetic resources should be considered urgently and some conservation measures should be adopted. In addition, the continuing development of molecular biology will further enhance conservation of diversity of Chinese indigenous goat breeds.

• Journal of Animal Environmental Science
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• v.20 no.4
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• pp.177-182
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• 2014

This research was conducted to grasp the present condition of environmental management relating to Korea detector dogs that performed their duties such as detection and lifesaving. We directly conducted a survey throughout visit to five government agencies. In environmental management case, average length and width of kennels were 1.78 m and 3.50 m, respectively. Types of floor were searched as coating cement, tile, ucrete and concrete. Most of government agencies ventilated kennels using ventilation fan systems with natural ventilation. But there were differences between government agencies in frequencies of the sanitary management items. On the other side, major diseases of the German shepherd breed as a major detector dog were in order of arthritis, measles, earache, and dermatosis. And their daily training time was average 4 hours. Finally, it is thought that these results could be used as a basic data of standard breeding management manual of Korea detector dog.

• Korean Journal of Breeding Science
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• v.43 no.5
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• pp.349-359
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• 2011

Agriculture plays a vital role in the sustenance of human society and is the fundamental of developing economies. Nitrogen is one of the most critical inputs that define crop productivity. To ensure better value for investment as well as to minimize the adverse impacts of the accumulative nitrogen species in environment, improving nitrogen use efficiency of crop plants is of key importance. Efforts have been made to study the genetic and molecular biological basis as well as the biochemical mechanisms involved in nitrogen uptake, assimilation, translocation and remobilization in crops and model plants. This review gives an overview of metabolic, enzymatic, genetic and biotechnological aspects of nitrogen uptake, assimilation, remobilization and regulation. This review presents the complexity of nitrogen use efficiency and the need for an integrated approach combining physiology, quantitative trait genetics, system biology, soil science, ecophysiology and biotechnological interventions to improve nitrogen use efficiency.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.285-291
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• 2018

The impact of climate change on animals has been globally documented. Especially, migration of birds has been extensively monitored as migratory birds are susceptible to any changes occurring both on breeding grounds and on wintering grounds. However, in contrast to spring migration, the patterns and the factors for autumn migration have not been well documented. In this study, we investigated the relationship with climate condition and the first arrival dates (FADs) of bean geese (Anser fabalis) and white-fronted geese (A. albifrons), the representative group of wintering birds in South Korea, using the data collected by Korean Meteorological Association during 1995-2016. Average temperature of September in wintering grounds has increased, and the FADs of the geese have advanced over the 22 years. Even when the influence of autumn temperature was statistically controlled for, the FADs of the geese have significantly advanced. This suggests that warming has hastened the completion of breeding, which speeded up the arrival of the geese at the wintering grounds. In order to assess the effect of climate condition on the arrival of the wintering migratory birds such as the geese in more detail, extensive data collection over many sampling sites and with long-term monitoring is needed.

• Journal of Ecology and Environment
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• v.48 no.3
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• pp.214-221
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• 2024

Background: To identify and avoid predators, amphibians rely on chemical cues. Onychodactylus koreanus undergo two to three years of the larval stage in mountainous streams, where they encounter various predators. We aimed to identify the potential predators of O. koreanus larvae based on their antipredator responses to predator odors. Additionally, we examined whether the response was innate or can be strengthened by predator olfactory learning. Results: In Experiment 1, O. koreanus larvae exhibited a substantial antipredator response to Chinese minnow (Rhynchocypris oxycephalus) odor but not to Korean freshwater crayfish (Cambaroides similis) odor. In Experiment 2, O. koreanus larvae, who did not previously expose to R. oxycephalus odor, demonstrated a substantial antipredator response to it. Experiment 3 indicated that predator olfactory learning of R. oxycephalus did not enhance the antipredator response of the larvae. Conclusions: Rhynchocypris oxycephalus could prey on O. koreanus larvae, whose antipredator response to R. oxycephalus odor is innate and not enhanced by olfactory learning. Further investigation into the olfactory system of this species may provide insights into the life cycle of O. koreanus, uncovering hidden underground breeding sites and unknown breeding periods.

• Korean Journal of Environment and Ecology
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• v.23 no.6
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• pp.564-568
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• 2009

The principal objective of this study was to determine and characterize the food resources and foraging sites of Pacific Reef Herons bred in Aewol-eup, Jeju Island, during Feb. 2005 ~ Aug. 2005. The food resources of Pacific Reef Herons were identified as comprising 21 individuals of 5 species, and these identifications were verified as follows: 38.1% of Tridentoger obscurus(n=8), 19.0% of Ennedpterygius etheostomus(n=4), and 14.3% of Engraulis japonica(n=3). The sizes of the food resources were measured as follows: total $58.29{\pm}5.17mm$(n=19), T. obscurus was $67.49{\pm}4.91mm$(n=8), E. etheostomus was $43.98{\pm}3.50mm$(n=4), and E. japonica was $22.77{\pm}1.17mm$. The semi-digested foods were confirmed as Paralichthys olivaceus and Sebastes inermis. The primary foraging sites were 7.4km(Oedocheon) east, to 6.6km(Geumseongcheon) west of the Aewol breeding area.

• Journal of Microbiology and Biotechnology
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• v.17 no.7
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• pp.1106-1112
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• 2007

This report provides the complete nucleotide sequences of the full-length cDNA encoding squalene synthase (SQS) and its genomic DNA sequence from a triterpene-producing fungus, Ganoderma lucidum. The cDNA of the squalene synthase (SQS) (GenBank Accession Number: DQ494674) was found to contain an open reading frame (ORF) of 1,404 bp encoding a 468-amino-acid polypeptide, whereas the SQS genomic DNA sequence (GenBank Accession Number: DQ494675) consisted of 1,984 bp and contained four exons and three introns. Only one gene copy was present in the G. lucidum genome. The deduced amino acid sequence of Ganoderma lucidum squalene synthase (GI-SQS) exhibited a high homology with other fungal squalene synthase genes and contained six conserved domains. A phylogenetic analysis revealed that G. lucidum SQS belonged to the fungi SQS group, and was more closely related to the SQS of U. maydis than to those of other fungi. A gene expression analysis showed that the expression level was relatively low in mycelia incubated for 12 days, increased after 14 to 20 days of incubation, and reached a relatively high level in the mushroom primordia. Functional complementation of GI-SQS in a SQS-deficient strain of Saccharomyces cerevisiae confirmed that the cloned cDNA encoded a squalene synthase.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2006.10a
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• pp.86-96
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• 2006

To provide some ecological informations for protection and management of mixed heronries, their distribution, breeding species and individuals, and site characteristics that may be important to heron ecology were investigated in Jeollanam-do during 2005 breeding season. During the study, 17 mixed heronries, containing a total of six ardeid species were found. Of them, Great Egret(Egretta alba) and Grey Heron(Ardea cinerea) bred in most sites(both 92%) and were most numerous(36.3%, 31.0% respectively). Many of heronries(53.3%) were located within the bamboo forest. Other site characteristics were as follows: the mean area of heronry was $2346m^2$ with range of $500-7,000m^2$, the mean distance between nearest two heronies was 18.1km with range of 5.6-40.4km, the mean distance to nearest village was 297m with range of 10-2,000m, the mean gradient of the topography was $18^{\circ}$ with range of $2^{\circ}{\sim}40^{\circ}$, and 40.0% of heronries were located in the eastern slope.