• Korean Journal of Organic Agriculture
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• v.13 no.4
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• pp.423-433
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• 2005

This study was conducted to develope efficient vermicomposting using of different mixture ratios of cow manure and sawdust by feeding these to earthworm and then by studying the growth and reproductive efficiency of earthworm, and the chemical composition of worm cast and its production. The results are summarized as follows. C/N ratio of feed was $20.43{\sim}45.20$ and it increased according to the higher proportion of sawdust, and survival of earthworm was $97.6{\sim}100%$. Number of young worms were significantly higher in 30 and 40% addition of sawdust (number of 899.6 and 927.8) than number of 769 of real cow manure treatment (P<0.05). Fresh weight of young worms was $8.00{\sim}14.35g$ and it was significantly higher in 40% addition of sawdust than other treatments(P<0.05). The cast production of earthworm was showed in the tendency of becoming lower in the 40% addition of sawdust than in $10{\sim}30%$ addition of that, but digested matters were significantly higher in $10{\sim}40%$ addition of sawdust than real cow manure treatment(P<0.05).

• Advances in environmental research
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• v.12 no.1
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• pp.51-64
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• 2023

The sustainable management of rice straw is essential for protection of human health and environment. This study assesses the impact of stock density of earthworm (Eisenia fetida) and Neem leaves (Azadirachta indica) on the quality of the final vermicompost. The vermicompost is produced using different combinations of rice straw, Neem leaves, and cow dung (bulking agent) by varying stock density of earthworms. The vermicomposting experiments are performed in plastic containers (32 cm × 28 cm × 28 cm) in open for 90 days under laboratory conditions. The stock density of the earthworm is found to be an important factor to influence nutritional quality of the final vermicompost. There is observed significant improvement in the total nitrogen (91.8%), phosphate (73.4%), potassium (38.8%), and calcium (59.05%) content of the vermicompost produced with the highest stock density of the earthworms. All the treatments showed decrease in TOC and C:N content after 90 days of vermicomposting. The treatment with Neem leaves showed maximum growth of earthworms (2.65 fold). Neem leaves brought positive changes in the quality of final vermicompost by enhancing the growth and reproduction of the earthworms. The calcium content increased by 39% in the final vermicompost with the addition of Neem leaves at the same stock density of the earthworms. The stock density of the earthworms and Neem leaves are found to significantly improve quality of the final vermicompost as compared with the compost (control). The surface morphology in SEM images showed high degree of fragmentation in the vermicompost as compared with the compost. The combined action of microbes and earthworms resulted in high degree of disintegration in the vermicompost.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.3
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• pp.35-41
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• 2003

The on-site sewage sludge vermicomposting equipment was designed and evaluated on the batch and continuous tests. The vermicomposting equipment was designed to consider the mechanization as well as automation. Especially, the automatic controls of water content and temperature and the mechanization of the sludge feeding and cast separating were the important factors. In terms of changes in chemical characteristics when the equipments for experiments are operated continuously, the ORP, EC, $NH_3-N$ and $NO_3-N$ were found to be higher before and after treatment. In addition, it was found that changes in properties were low. Furthermore, the $NO_3-N$ concentration of the humus produced after treatment was found to be higher than the $NH_3-N$ concentration showing that it was appropriate based on the recycling criteria.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.1
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• pp.57-66
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• 2014

The present study was conducted to provide basic data for environmentally friendly treatment of manure using vermicomposting. This was done by investigating the influence of physiochemical property change during the composting period on the survival of earthworms after mixing cow manure in different levels (0(CRH0), 10(CRH10), 20(CRH20), 30(CRH30), and 40%(CRH40)) with the rice hull that is generally added for composting manure. As composting proceeds, earthworms were able to survive in all conditions after 3 weeks. In terms of the C/N ratio by treatment groups, the rice hull mix treatments were significantly higher than the CRH0 treatment. Among rice hull mix treatments, the treatments with 30~40% rice hull level (CRH30 & CRH40) showed the highest ratio out of all composting periods (p<0.05). The C/N ratio in the 3rdweek when earthworms started surviving was 23.26~34.44. As composting progressed, pH and electrolytic conductivity (EC) were the highest in the CRH0 treatment (p<0.05) and tended to decrease with higher proportion of rice hull in the mix. It was found that pH and electrolytic conductivity (EC) that earthworms start to survive are 7.58~7.74 and 0.41~1.17 mS/cm, respectively. To summarize, when composing cow manure with various levels of rice hull mix, all physiochemical property changes turned out to allow the survival of earthworms, but the results suggest that efficient vermicomposting requires the tests to examine the growth and reproduction according to the rice hull mix ratio.

• Korean Journal of Organic Agriculture
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• v.22 no.1
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• pp.183-195
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• 2014

The present study was conducted to provide basic data for environmentally friendly treatment of manure using vermicomposting by investigating the influence of physiochemical property change during the composting period on the survival of earthworms after mixing cow manure in different levels (0(CSD0), 10(CSD10), 20(CSD20), 30(CSD30), and 40%(CSD40)) with the sawdust that is used bedding in livestock pens. As composting proceeds, earthworms were able to survive in all treatments after 3 weeks. In terms of the C/N ratio by treatment groups, the sawdust mix treatment was significantly higher than the CSD0 treatment (p<0.05). The C/N ratio in the 3rdweek when earthworms started surviving was 23.26-61.05. As composting progressed, pH and electrolytic conductivity were highest in the CSD0 treatment and tended to decrease with higher proportion of sawdust in the mix. It was found that pH and electrolytic conductivity that earthworms starting to survive are 7.4-7.7 and 0.28-1.17 mS/cm respectively. To summarize, when composing cow manure with various levels of sawdust mix, all physiochemical property changes turned out to allow the survival of earthworms, but the results suggest that efficient vermicomposting requires the tests to examine growth and reproduction according to the sawdust mix ratio.

• Journal of the Korea Organic Resources Recycling Association
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• v.14 no.4
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• pp.104-112
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• 2006

Population growths of earthworm were investigated when the earthworm populations with different levels of initial densities per unit area were fed with cow dung mixed with paper mill sludge. The tested levels of earthworm densities were as follows; $1kg/m^2$, $2kg/m^2$, $3kg/m^2$, $5kg/m^2$. There were no significant differences in population growth rates 60 and 90 days after feed supply among the tested densities of earthworm. Therefore, it was suggested that initial densities of earthworm populations per unit area higher than $3kg/m^2$ should not be favorable because of the cost for purchasing earthworm. Vermicomposting rates of earthworm on feed were also investigated when different amounts of feed were supplied repeatedly to unit area of nursery bed with $5kg/m^2$ of initial densities earthworm populations. The tested amounts of feed at each supplying time were as follows; $16kg/m^2$, $24kg/m^2$, $32kg/m^2$, $40kg/m^2$. The more the amount of feed at each supplying time, the higher vermicomposting rate and population growth rate. Therefore, it should be more favorable for earthworm breeders to supply more than $40kg/m^2$ of feed at each supplying time, because it would reduce time and labor cost.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2004.12a
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• pp.1-16
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• 2004

This study was conducted to investigate effects of different ratios of sawdust to poultry manure as an earthworm feed on the change of physico-chemical characteristics and earthworm viability during composting, and further to provide the basic information for an efficient vermicomposting using the manure of livestock. Experimental earthworm used in this study was Eisenia foetida and the ratio of sawdust and poultry was determined to 100:0(A), 80:20(B), 70:30(C), 60:40(D) and 50:50(E) on the basis of volume. The results are summarized as follows. Earthworm appeared after 6 wk of aging period, and it was possible for the earthworm to survive in treatments of C. D and E including 30 $^{\sim}$ 50% of sawdust. C/N ratio was significantly higher (P<0.05) in treatments of sawdust mixture (B, C, D, and E) than poultry manure alone (A treatment).Appropriate C/N ratio for earthworm survival was the range of 16.9 to20.7. During period of aging, pH value and electrolyticconductivity (EC) were the highest in the treatment of poultry manure alone. However, as the inclusion of sawdust was increased, pH showed decreasing tendency. Appropriate pH and EC for earthworm survival were 7.69 to 7.79, and 2.77 to 2.87mS/cm, respectively. The results from this study indicated that the mixing of poultry manure with sawdust more improved physico-chemical environment for earthworm growth in comparison with poultry manure alone, and sawdust showed the sufficient possibilityas a bulking agent for an efficient vermicomposting of poultry manure.

• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.2
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• pp.39-45
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• 1997

This study was performed to investigate the growth response of earthworm (Eisenia foetida) in cow manure added Cadmium (Cd) and therefore, to estimate the toxic threshold level of Cadmium and the levels of Cadmium in cow manure for obtain-ing the maximum Cadmium-concentration enable to accumulate in earthworm tis-sue. Seven different concentrations of Cadmium added in cow manure were 0 (control), 50, 100, 200, 400, 800, 1600 mg/kg, respectively. Survival rate (SR), mean fresh weight of adult worm at final time ($FW_2$), increasing rate (IR), number of cocoon (NC), number of young worm (NY) and residual matter (RW) were not significantly different among Cadmium concentrations in cow manure. Of the measured growth-characteristics, survival rate (SR) had a significantly positive correlation (p<0.001) with number of cocoon (NC). But mean fresh weight of adult worm at final time ($FW_2$) had a significantly negative correlation (p<0.05) with residual matter of cow manure. The maximum Cadmium concentration accumulated in tissue was ranged from 283.8 mg/kg to 396.2 mg/kg. It was obtained at the level of 956.5 mg/kg and 1116.6 mg/kg in cow manure added Cadmium, respectively.

• Korean Journal of Organic Agriculture
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• v.14 no.4
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• pp.421-431
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• 2006

This study was conducted to develope efficient vermicomposting using of different mixture ratios of cow manure and rice hull by feeding these to earthworm and then by studying the growth and reproductive efficiency of earthworm, and the chemical composition of worm cast and its production. The results are summarized as follows. C/N ratio of feed was $20.43{\sim}31.16$ and it increased according to the higher proportion of rice hull, and survival of earthworm was $97.6{\sim}98.4%$. Number of young worms were significantly higher in $10{\sim}40%$ addition of rice hull(number of $824{\sim}844$) than number of 769 of real cow manure treatment(P<0.05). Fresh weight of young worms was $8.00{\sim}11.8g$ and it was significantly higher in 40% addition of rice hull than for other treatments(P<0.05). The cast production of earthworm was significantly lower in the 40% addition of rice hull than for other treatments(P<0.05). But digested matters were showed in the tendency of becoming higher in the 40% addition of rice hull than in $10{\sim}30%$ addition of that. C/N ratio of worm cast was significantly higher in 40% addition of rice hull than for other treatments(P<0.05). Heavy metal concentrations of worm cast were showed in the tendency of becoming lower in the 40% addition of rice hull than in addition of that.

• Journal of the Korea Organic Resources Recycling Association
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• v.4 no.2
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• pp.35-45
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• 1996

In order to investigate the possibility of treating nightsoil sludge, the growth trend experiments with vermicompsting was performed and the stability of worm castings was evaluated by the analysis of minerals according to growth periods. Survival rate(SR) of earthworms decreased as earthworms grow up to 7 weeks. The growth period of the earthworms could be classified into two phases on the basis of the ratios of cast to feed ingested(ID). The growth period of the earthworms up to 3 weeks, the high percentage of dry weight of feed ingested(ID) is mainly utiliz-ed to an increase in fresh weight of earthworms, and after the 3 weeks, it is utilized to cast production in this experiment, respectively. The highest values of increasing rate(IR) and biomass of the earthworms(BE) were obtained at 3 weeks and those were 10.59mg/day and 14.48g, respectively. Between the increasing rate(IR) and biomass of the earthworms(BE), a highly positive correlation coefficient(p<0.001) ap-peared. The highest values of biomass of the earthworms(BE) and cast production(CW) were obtained at 3 and 7 weeks, respectively. All the concentrations of minerals except calcium(Ca) in worm castings was lower than the values in nightsoil sludge. It was considered that the major portion of minerals in nightsoil sludge may have been retained in the bodies of earthworms. And these values were lower than the regulated levels in organic fertilizers that the regula-tion standards. In conclusion, the worm castings are very stable for the use as soil conditioner or organic fertilizers.