• The Journal of Fisheries Business Administration
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• v.43 no.3
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• pp.43-57
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• 2012

According to the result of the recent survey on the current condition of loss of the fishing gears in the East, West and South seas, it is estimated that 50% of the fishing gears used for coastal trap and gill net fisheries are lost every year and 20~30% of those used for inshore trap and gill net fisheries are lost. It is reported that such loss of fishing gears leads to the loss of about 10% of 1.7M tons of the total annual catch from the gill nets and traps along the country's coasts and shores, which amounts to 15~170K tons. Submerged marine litters that have recently been accumulated because of the washed out or lost fishing gears significantly affect the development of fisheries resources as well as the natural environment. The purpose of this study is to identify the damages that the ever-increasing submerged marine litters of washed out fishing gears would have on the fishery and to analyze the effects of the coastal and inshore submerged marine litter collection business on the fishery management. For this, the economic analysis was carried out for the coastal and inshore submerged marine litter collection business based on the fishermen's expenses and earnings and their catch. The result of the analysis shows that the submerged marine litter collection business is quite effective in certain areas but rarely effective in other areas. However, taking into consideration that the litter collection would contribute to protecting the marine environment as well as the fisheries resources, it is expected to have a significant impact on the protection of the marine environment even in those areas where it is not effective for the protection of the fisheries resources.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.598-602
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• 2004

The Tongcheng pig breed is a famous Chinese indigenous breed. The Ministry of Agriculture of China has filed it as 1 of 19 national key conservation breeds selected from more than 100 Chinese indigenous pig breeds in 2000. In order to improve the reproductive performance, it has been intensively selected to increase the litter size for about 10 years. The population randomly sampled from conservation nucleus of eight families in the Tongcheng pigs was genotyped for identification of their estrogen receptor locus polymorphisms with the PCR-RFLPs method. Only AB heterozygotes and BB homozygotes were detected, and $X^2$ test demonstrated that the locus was in disequilibrium at a significant level (p<0.05). In the present paper, the litter sizes in different parities were regarded as different traits. Holistic status of other unspecific and unidentified genes was estimated by using the statistical methods. Coefficients of kurtosis and skewness showed that the litter size still presented segregating characteristic in the 2nd, 5th, 7th, 8th and 9th parities. Analysis of homogeneity of variance between families confirmed the results for the 5th, 7th and 8th parities. The heritability of litter size for the 1st to 10th parities was estimated with paternal half-sib model and individual estimated breeding values (EBVs) were evaluated by a single trait animal model as well. We found that the averages of EBVs for litter size in each parity did not differ significantly between genotypes, despite the significant difference for original phenotype records in the 3rd, 4th and 5th parities (p<0.05 or p<0.01). The results may be explained by the deduction that the polymorphisms of ESR locus are no longer the important genetic base of litter size variation when the frequency of allele B accumulated in the experience of selection procedure, and further conferring that there exist special genes associated with litter size in the recent Tongcheng pigs population can be made.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.381-386
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• 2004

To develop accurate and predictive global carbon cycle models, it is important to understand the change of accumulated carbon for many ecosystems according to successional stage. In this study, I measured total biomass, litter and soil organic matter contents through an aerial photo and field observation. As a result, accumulated organic matter contents per unit area (kg $m^{-2})$ of three communities composed at grassland were 7.00 kg $m^{-2}$, in Solidago altissima community, 9.18 kg $m^{-2}$, in Imperata cylindrica community, and 12.68 kg $m^{-2}$, in Miscanthus sinensis community, respectively. Accumulated total organic matter contents was high in Miscanthus sinensis community at later succession stage but soil carbon was low. In Miscanthus sinensis community, highly accumulated organic matter contents was resulted from increasing of biomass comparison with that of the other two communities. The pattern of accumulated organic matter contents was changed by changing of the dominant community due to progressing in succession. The accumulated carbon in temperate grassland will be increased with progressing in succession.

• Journal of Animal Environmental Science
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• v.13 no.3
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• pp.211-218
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• 2007

This study was carried out to develop the technique for manufacturing activated carbon from livestock manure and to analyse it's odor absorptiveness. Each of layer manure(LM), litter from broiler house(BL) and litter from dairy barn(DL), compost from layer manure(LC) and pig manure(PC), and coconut shell(CS) was used as a raw material. Activated carbon by grinding the raw material, adding the coal tar as a binder, palletizing, drying, heating with $N_2$ gas at $400^{\circ}C$ for 1 hour, activating by reaction with steam at a temperature of $750^{\circ}C$ for 1 hour. Moisture contents of raw material was 44.9% in layer compost, 71.9% in layer manure, 24.4% in broiler litter, 47% in pig manure compost and 33.9% in dairy litter. Volatile matter in layer compost, layer manure, broiler litter, pig manure compost and dairy litter was 18.8%, 31.0%, 49.8%, 22.3% and 11.6%, respectively. Surface area(BET) of activated carbon from layer compost, layer manure, broiler litter, pig manure compost, dairy litter and coconut shell was 259.8, 209.8, 63.5, 442.3, 812.9 and $1,040\;m^2/g$, respectively. Activated carbon made by livestock manure or litter were examined with scanning electron microscope, and micropore was a type of sponge like particles honeycombed with chambers. Pore size of activated carbon was ranged from 0.39 to $5.02\;{\AA}$, but coconut shell was $0.30\;{\AA}$. Iodine absorptiveness of activated carbon from livestock manure was $530{\sim}580mg/g$. But activated carbon made by coconut shell was 1000 mg/g. Each activated carbon could absorb odor compound very well. Absorptiveness of activated carbon from layer manure for hydrogen sulfide and trimethyl amino was 74.5% and 73.9% at the accumulated flux of 60,000 ml, but, in the case of ammonia was only 15.2% at the accumulated flux of 10,000 ml

• Korean Journal of Environment and Ecology
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• v.24 no.4
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• pp.426-435
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• 2010

The present study attempts to compare the soil chemical characteristics and biological activities (i.e. microbial biomass and soil enzyme activities), and litter decomposition rate of Arundinella hirta and Miscanthus sinensis var. purpurascens) collected from serpentine and non-serpentine sites by litter bag techniques at serpentine and non-serpentine field experiment sites over a 9-month period. The serpentine soil showed higher pH and soil alkaliphosphatase activity, and lower soil dehydrogenase and urease activities than the non-serpentine soil. Microbial biomass-N at the serpentine soil was larger than the non-serpentine soil, although the microbial biomass-C and microbial biomass-N represented no significant difference between serpentine and non-serpentine soil. These results suggest that the larger microbial biomass-N caused the lower C/N in serpentine soil. At the end of the experiment, the litter samples of A. hirta and M. sinensis collected from serpentine soil revealed a 39.8% and 38.5% mass loss, and the litter sample from non-serpentine soil also showed a 41.1% and 41.7% mass loss at the serpentine site. On the other hand, at the non-serpentine site, 42.2%, 37.4%, and 46.8%, 44.8% were respectively shown. These results demonstrate that the litter decomposition rate is more intensely affected by the heavy metal content of leaf litter than soil contamination. Moreover, the litter collected from the serpentine soil had a lower C/N, whereas the litter decomposition rate was slower than the litter from the non-serpentine soil, because the heavy metal inhibition activities on the litter decomposition process were more conspicuous than the effect of litter qualities such as C/N ratio or lignin/N. The nutrient element content in the decomposing litter was gradually leached out, but heavy metals and Mg were accumulated in the decaying litter. This phenomenon was conspicuous at the serpentine site during the process of decomposition.

• Asian Journal of Turfgrass Science
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• v.10 no.4
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• pp.275-283
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• 1996

An investigation was performed to reveal the relation between the storage and decomposition of the titter DNA of a Zoysia japonica grassland on Mt. Kwanak. The loss constant k of litters was 0.167. The times required for the decomposition of half, 95% and 99% of accumulated DNA on the grassland floor were 3.8, 16.6 and 27.6, respectively. The amount of DNA which is turned to living organism in the ecosystem is higher than that of crude protein. In the case of crude protein, the decay constant k was 0.181. The times needed for the decomposition of half, 95% and 99% of accumulated crude protein on the Z. japonica grassland floor were 3.8, 16.6 and 27.6 years, respectively. Key words: Zoysia japonica, Mt. Kwanak, Litter DNA, Crude protein, Decomposition, Accumulation.

• The Korean Journal of Ecology
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• v.8 no.3
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• pp.163-169
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• 1985

The composition rates of litters were studied at Camellia japonica forests in Koje-Do and Haenam, and at Quercus acuta, Quercus acutissima, Cryptomeria japonica, and Chamaecyparis abtusa forests in Haenam. Total amounts of nitrogen, phosphorus, potassium, calcium, and sodium in litter samples were measured and the relation between these amounts and decomposition rate was studied. Annual litter production were rarely different at each forest in Haenam. The amount of accumulated organic matter was about 4 times greater at C. japonica forest in Koje-Do than at the C. japonica forest in Haenam. These amounts were 5, 282.1 $\pm$ 1, 026.03g/m2 in Koje-Do and 1, 420.7 $\pm$ 384.77g/$m^2$ in haenam. The decomposition rate were rarely differnet at each forest in Haenam, but the rates showed great difference at C. japonica foreests in Koje-Do and Haenam. The rates were 0.093 and 0.313 at C. japonica forests in Koje-Do and in Haenam respectively. The sodium contents were 0.472% and 0.229% on L layer and on Css layer of C. japonica forest in Koje-Do, while they were 0.034% and 0.043% on L layer, and on Css layer of C. jpaonica forest in Haenam. It is sugested that much difference in the salt contents in the forest floor was present from the results of sodium content measured at each site, and that the decomposition rate was affected by the much concentration of salt in Koje-Do.

• Korean Journal of Microbiology
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• v.6 no.3
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• pp.92-92
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• 1968

1) The aim of present investigation is to elucidate the relation of the balance of the production and decomposition of the fir litter. in Kwangnung plantation stands. 2) The decay constant, K, of litters was 0. 185 for the fir stand at Kwangnung. 3) The mode for the accumulation of organic carbon ($C_a$) is $c_a$= $610(1-e^{-0.185t})$), and for the decay of organic carbon (C) C = $610(1-e^{-0.185t})$. 4) The time required for the decay of half of the accumulated organic carbon in the fir stand is 3. 74 years and for 99% of elimination 27.02 years. 5) The litters of Abies holophylla killed by heat and washed with alcohol-benzol, with hot water, or with both alcohol-benzol and hot water were incubated after inoculated with suspension of firwood soil. Plate counts were made of fungi and bacteria from time to time. 6) Removal of the alcohol-benzol soluble substance stimulates at the beginning of the decay the growth of fungi and also of bacteria. 7) Removal of the water soluble fraction is detrimental to the growth of fungi in particular. 8) The distribution of soil microbial population is higher in both F and H horizon of the fir plantation soil in Kwangnung. However, the number of soil microorganisms decreases with the depth in forest soil.

• Korean Journal of Microbiology
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• v.6 no.3
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• pp.93-99
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• 1968

1) The aim of present investigation is to elucidate the relation of the balance of the production and decomposition of the fir litter. in Kwangnung plantation stands. 2) The decay constant, K, of litters was 0. 185 for the fir stand at Kwangnung. 3) The mode for the accumulation of organic carbon ($C_a$) is $c_a$= $610(1-e^{-0.185t})$), and for the decay of organic carbon (C) C = $610(1-e^{-0.185t})$. 4) The time required for the decay of half of the accumulated organic carbon in the fir stand is 3. 74 years and for 99% of elimination 27.02 years. 5) The litters of Abies holophylla killed by heat and washed with alcohol-benzol, with hot water, or with both alcohol-benzol and hot water were incubated after inoculated with suspension of firwood soil. Plate counts were made of fungi and bacteria from time to time. 6) Removal of the alcohol-benzol soluble substance stimulates at the beginning of the decay the growth of fungi and also of bacteria. 7) Removal of the water soluble fraction is detrimental to the growth of fungi in particular. 8) The distribution of soil microbial population is higher in both F and H horizon of the fir plantation soil in Kwangnung. However, the number of soil microorganisms decreases with the depth in forest soil.

• Asian Journal of Turfgrass Science
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• v.11 no.4
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• pp.281-288
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• 1997

This study was performed to find out the mineral cycles of sulphur in dynamic grassland ecosystems in a steady state condition at the northwest side on Mt. Kwanak. The experimental results may be summarized on the communities of a Zoysia japonica and a Miscanthus sinensis as follows. As compared with some properties of the surface soils among two semi-natural grasslands, sulphur war greater quantity in a Miscanthus sinensis than in a Zoysia japonica on Mt. Kwanak . For the case of steady production and release, the raion of annual mineral production to the amount accumulated on the top of mineral soil in a steady state provides the estimates of release constant k. The release constants on sulphur of the litter were 0.54 in a Zoysia japonica and 0.36 in a Miscanthus sinensis grassland. The half times of S required for the release or accumulation of the litter on the grassland were 1.28 years in a Zoysia japonica and 1.93 years in a Miscauthus sinensis The amounts of annual cycles for sulphur in the grassland ecosystem under the steady-state conditions were 20.65g /$m^2$ in a Zoysia japonica and 26.28g /$m^2$ in a Miacanthus sinensis grassland. Key words: Zoysia japonica Miscanthus sinensis Mt. Kwanak, Sulphur, Mineral cycles.