• The Korean Journal of Malacology
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• v.9 no.2
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• pp.85-93
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• 1993

Contamination of heavy metals in water and sediments along Mantyeong (river) has reached up to critical level, The object of the study is to dlucidate some macroinvertebrates which inhabit along the river in respect to the modulatory role in reducing the pollution. For the purpose, Scapharca subcrenata(sea shell) which is common in numbers and biomass in the area was collected, and cadmium (Cd) was subjected as a reference metal in the experiment. The seashell was dried and autoclaved, followed by pellet preparation under various concentration of Cd: 50,100,250,500 and 1,500 ug /pellet. Mice were fed for 3 months, althrough last group(5 mice), 1,500 ug/pellet, died within 4 weeksof the administration.MT-Cd in liver and kidney increased in correlation with the amont of Cd concentration in pellet, especially in kidney than in liver. Liver and kidney of the mice showed pathological changes such as cellular infiltration and focal necrosis in liver, and peri-tubular cell infiltration or tubular necrosis etc. The changes were more intensive by amount of the Cd. Overall results in the present study suggest that Cd may eventually combine with soluble-protein forming metalloprotein, then reduce the toxicity of heavy metal, How the formed Mt-Cd is discharged from the kidney and the mechanism shall be the further subject to be clarified.

• Journal of the Korean Institute of Landscape Architecture
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• v.14 no.2
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• pp.7-16
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• 1986

This study was carried out to investigate the effects of such erosion control measures as sowing, planting and small earth structures on the soil and vegetation. In order to study the changes in soil and vegetation, 36 plots were surveyed from 1981 to 1982 in the large erosion control area which is restored last 20 years. The factors which were measured included vegetation coverage, tree growth, number of species, soil depth, soil consistancy, and Chemical properties of soil. The results were as follows; 1) Maximum coverage of the overstory and understory was attained 7 years after the initiation of erosion control. So the overstory need to be tended and pruned. 2) Diversity of species increased until age 6 after which it began to decrease. 3) In order of tree growth, black locust was the fastest, followed by siberian alder and pitch pine. The initial growth of black locust, though the best among the 3 tree stop., decreased rapidly year by year. At the same time, siberian alder and pitch pine grew well until 12 and 6 years after the initiation of erosion control respectively. 4) Fifty percent of the initially planted trees died within 8 yeard. The mortality of siberian alder occurred until the 20th year while the mortality of pitch pine stopped after 10 years. Thereafter 500 trees per hectare were maintained. 5) The soil depth in A and B horision increased by 2cm annually during 20 years. The soil consistency also decreased rapidly until 7th year. The physical soil properties of the rehabilitated areas were improved after the 14th year. 6) The soil pH tend to decrease from 5.3 during the first year to 5.1 during the twentieth year. 7) The organic matter and nitrogen content in the soil were increased by fertilization but after 20 years these nutrients are still deficient for normal tree growth. 8) The phosphorous content in the soil was high in the first year but the longer the period after the initiation of erosion control the lese the content of phosphorous. 9) The biomass of black locust was the highest and increased continuously. The biomass of siberian alder on the contrary decreased from the 15th year because the number of trees in this place was very low. The total biomass in the twentieth year after erosion control initiation was 105.7 ton per hectare.

• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.3
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• pp.51-62
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• 2005

The effects of the processing mixture of food wastes and various organic wastes when vermicomposted on earthworm(Eisenia foefida) growth, the cast production amounts and the chemical properties of casts were evaluated. The substrates used in this experiments were cow manure, pig manure sludge, fermented pig manure with sawdust, nightsoil sludge, and sewage sludge and were respectively mixed with food wastes at a ratios of 50:50(v/v). The control consisted of food wastes alone without other wastes. All of earthworm died in the food wastes 100%, therefore the process of food wastes alone by vermicomposting was impossible in this experiment. Worm cast produced sufficiently contained quantities of available phosphorus, exchangeable potassium, exchangeable magnesium, and cation exchange capacity. The increase of earthworm's biomass occured on the mixtures of food wastes and cow manure, fermented pig manure with sawdust. Dry weight of worm cast was the highest on the mixtures of food wastes and fermented pig manure with sawdust and the proportion of cast weight after vermicomposting was significantly the highest on the mixtures of food wastes and cow manure($p{\leq}0.05$). Also, the mixtures of food wastes and cow manure, and fermented pig manure with sawdust showed a positive values of conversion rate and conversion efficiency rate of organic matter to earthworm tissue than that of other treatments. These results suggested that cow manure and fermented pig manure with sawdust are adequate to process with food wastes by vermicomposting.