This experiments was conducted to investigate the influence on organic rice cultivation by continuous use of cow manure in the central region of Korea and investigated productivity of organic rice and feed value, stock carrying capacity of organic rice straw. In the results, application of chemical fertilizer showed higher one of 1st and 2nd year in fresh matter yield (15.77, 30.30ton/ha), dry matter yield (9.90, 13.89 ton/ha), dry matter yield of rice straw (4.88, 7.15ton/ha), dry matter weight of kernel per plant (29.81, 39.99g) and number of kernel per plant (1212.58, 1701units), but there were not significantly differences with each experimental plots in 3rd year. And harvest index showed higher one in application of chemical fertilizer (0.52, 0.48, 0.43) until 3 years. But their quantitative difference between application of chemical fertilizer and cow manure was gradually decreased each year. And the average value of KCP and KTDN showed higher one in application of chemical fertilizer (2.01, 2.94, 1.95 head/ha/yr) until 3 years. However, quantitative difference between chemical fertilizer and cow manure was gradually decreased each year. Especially, application of cow manure showed higher value of 3rd year in KME, but there was not significantly difference with each experimental plots. According to the results, continuous use of cow manure will be reduced their quantitative differences between chemical fertilizer as the year progress in the central region of Korea in terms of productivity of organic rice and feed value, stock carrying capacity of organic rice straw.

This study was conducted to investigate the effect of cattle manure application on productivity, feed value, and stock carrying capacity of forage crops in upland and paddy fields at Gang-Wondo area. In the result, dry matter yield of sorghum x sudangrass hybrids obtained was 15.12 ton/ha at the level of 150kg N/ha of composted cattle manure. Significantly highest values of crude protein and total digestible nutrients (TDN) yields obtained were 0.59 and 5.35 ton/ha at the level of 150kg N/ha of composted cattle manure in the first cutting, and 0.44 and 3.70 ton/ha at the level of 150kg N/ha of organic raw cattle manure in the second cutting, respectively. The values of KCP+KTDN/2 and KME of sorghum × sudangrass hybrids obtained was 7.76 and 4.46 head/ha at the level of 150kg N/ha of composted cattle manure. The dry matter yield, crude protein and TDN yields of rice straw were 4.95, 0.16 and 2.75 ton/ha at the level of 100kg N/ha of organic raw cattle manure, and the values of KCP+KTDN/2 and KME of rice straw were 1.89 and 3.43 head/ha. The dry matter yield of winter crops, rye+red clover was 4.36 ton/ha in upland field, and rye+hairy vetch was 4.19 ton/ha in paddy field at the level of 100kg N/ha of composted cattle manure. Crude protein and TDN yields of rye+red clover was 0.29 and 2.38 ton/ha at the level of 100kg N/ha of composted cattle manure in upland field, and rye+hairy vetch was 0.30 and 2.48 ton/ha at the level of 80kg N/ha of composted cattle manure in paddy field. The values of KCP+Kㄴ/2 and KME of rye+red clover was 2.34 and 2.15 head/ha in upland field, and rye+hairy vetch were 2.27 and 2.11 head/ha in paddy field, respectively. As the result, the productivity, feed value, and stock carrying capacity of sorghum ×sudangrass hybrids showed higher values with composted cattle manure than organic raw cattle manure. rye+red clover in upland field and rye+hairy vetch in paddy field were most adaptable mixed combinations for roughage production at Gang-wondo area, it may due to their highly productivity, feed value, and stock carrying capacity.

This experiment was carried out to investigate the optimal stocking rate of earthworm populations grown under different stocking rates. The stocking rate in terms of ratio of biomass of earthworms to biomass of feeds(organic resources) is an important factors for biomass productivity of earthworms and vermicast production. The different stocking rates were 1:16(S-1), 1:32(S-2), 1:48(S-3) and 1:64(S-4), as the ratios of biomass of earthworm to biomass of organic dairy cow manure, respectively. The stocking rate of 1:32(S-2) and 1:46(S-3) were obtained a higher values on increasing rates and conversion efficiency of organic matter to earthworm biomass than other stocking rates. Thus, a stocking rates of 1:32 and 1:46 estimated an optimal stocking rates for maximum biomass productivity of earthworms. A stocking rate of 1:16(S-1) showed a significantly highest values of vermicast production and ratios of vermicasts during the rearing periods.(P≦0.05) A stocking rate of 1:48(S-3) showed a highest values of the number of cocoons and vermicasts production per earthworm biomass among the treatment (P≦0.05) The contents of nitrogen, available phosphorus, cation exchange capacity and exchangeable cations of vermicasts tended to increase with stocking rate and rearing progressed. Vermicasts have a great deal of potential for crop production and protection in sustainable organic cropping systems.