Effects of Mixing Ratios of Swine Manure and Rice Straw on Physico-Chemical Characteristics and Earthworm(Eisenia foetida) Survival

돈분에 볏짚 혼합 수준이 퇴비화 과정중 이화학적 성상 변화와 지렁이 생존에 미치는 영향

This study was conducted to investigate the effect of different ratios of rice straw to swine 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 swine manure and rice straw was determined to 100:0(SM), 90:10(SRS 10), 80:20(SRS20), 70:30(SRS30) and 60:40(SRS40) on the basis of volume. The results are summarized as follows. Earthworm appeared after 8 week of aging period, and it was possible for the earthworm to survive in all the treatments. C/N ratio was significantly higher (P<0.05) in the treatments of rice straw mixture (SRS30 and SRS40) than swine manure alone (SM treatment). Appropriate C/N ratio for earthworm survival was the range of 10.43 to 11.16. During the period of aging, pH value and electrolytic conductivity (EC) were the highest in the treatment of swine manure alone. However, as the inclusion of rice straw was increased, pH value and EC showed a decreasing tendency. Appropriate pH value and EC for earthworm survival were 7.7 to 7.8, and 2.72 to 4.59mS/cm, respectively. The results from this study indicated that mixing swine manure with rice straw more improved more physico-chemical environment for earthworm growth in comparison with swine manure alone, and rice straw showed the sufficient possibility as a bulking agent for an efficient vermicomposting of swine manure.

본 연구는 돈분에 볏짚을 0(SM), 10(SRS10), 20(SRS20), 30(SRS30) 및 40(SRS40)의 수준으로 혼합하여 부숙기간별 이화학적 변화를 측정하고 이를 바탕으로 생존율을 조사하여 가축분의 효율적인 vermicomposting의 기초자료로 이용하고자 실시하였다. 그 결과를 요약하면 다음과 같다. 부숙이 경과함에 따라 지렁이가 생존하기 시작하여 8주부터 지렁이의 생존이 가능하였다. 처리구별 탄질비는 볏짚 혼합구(SRS30과 SRS40)가 순수 돈분구보다 유의하게 높았다(P<0.05). 지렁이가 생존하기 시작한 8주째의 탄질비는 $10.43{\sim}11.16$으로 나타났다. 부숙이 경과함에 따라 pH와 전기전도도는 순수 돈분구에서 가장 높았고, 볏짚의 혼합 빈율이 높을수록 pH와 전지전도도는 낮은 경향이었다. 지렁이가 생존하기 시작한 pH와 전기전도도는 각각 $7.7{\sim}7.8$과 $2.72{\sim}4.59mS/cm$으로 나타났다. 이상의 결과를 종합해 보면 지렁이 먹이로써 돈분에 볏짚을 수준별로 혼합하여 부숙을 시켰을 경우 순수 돈분보다 이화학적 성상이 양호한 것으로 나타나 돈분의 효율적인 vermicomposting을 기대할 수 있었다.