| With the animal husbandry industry developing continuously, organic waste disposal problems in livestock and poultry farms such as sludge and manure has become a difficult and hot spots in China. The traditional methods of dealing with organic waste have disadvantages like high cost, complex technology, so they are hard to spread. Contrary to this, the vermicomposting technology has been widely used in some areas due to its characters of low carbon, no secondary pollution and recycling use. Based on the problems found in application, this study was conducted from two ways. On the one hand, earthworms which are at several growth stages were breeding with different waste in various proportion to find out the best feeding conditions. On the other hand, the effect of feeding frequency on the growth of worms was tested. The aim of this study was to provide technical support for practical application. The results are as follows:1. The cocoons show different hatching situations in different treatments, and the mixtures were better than single waste. With higher sludge, the number of hatched earthworms for each worm cocoon was more, and the total number of incubated cocoons was higher, but the time consistency of hatching was poor. With higher cow dung, the number of hatched earthworms, and the total number of incubated cocoons were low, the time consistency of hatching was poor, and the number of death cocoons was a little more. Under the condition of 20 cocoons were incubated in each treatment groups, the maximum number of the hatched cocoons was 19.33 in the treatment of 20% cow dung and 80% sludge in the first 15 days; it was 16.50 in 20% sludge and 80% pig manure treatment during the first 13 days to 15 days; the maximum number of death cocoons was 2.33 in 100% cow dung treatment; the highest number of small earthworms was 92.67 in 80% and 20% manure sludge treatment.In the infancy stage, earthworms showed higher growth rate in mixtures with more cow dung, middle growth rate in mixtures with more pig manure, and poor growth performance in mixtures with more sludge. The highest weight of earthworms was 0.0467g obtained in 100% cow dung.In the young stage, earthworms in the treatment groups with more cow dung showed better growth performance, followed by with more sludge, and pig manure. The highest average weight of earthworms was 0.6013g obtained in treatment with 80% cow dung and 20% pig manure.In the adult stage, the reproduction of earthworms in mixtures was better than in single wastes. The largest cocoon production was 537 obtained in 40% sludge+60% pig manure treatment, and it’s low in pig manure+cow dung mixtures. The higher average weight of earthworms was obtained in treatment with more cow dung, and the maximum value was 0.6797g.The fertility of substrates was analyzed after vermicomposting by young and adult worms. The reduction of dry weight in treatment with more pig manure was higher. And the most reduction rate was 35.21% in 60% sludge and 40% pig dung mixture during young stage while it was 27.37% in 40% sludge and 60% pig dung during adult stage. The highest reduction rate of total organic carbon was found in the treatments with more cow dung, so was the ammonium nitrogen. Besides, the highest increment rate of total potassium and total phosphorus concentration was illustrated in treatments with more pig manure. And the quantity of nitrate nitrogen and Olsen-P was high in mixtures with cow dung and pig manure.2. The frequency of adding organic waste affected the earthworm growth and quality of vermicomposts. The highest biomass of worms was 0.1387g when the organic waste was provided per 7 days. With this adding interval, the minimum quantity of total organic carbon, the maximum quantity of total nitrogen, total phosphorus, Olsen-P and ammonium nitrogen were obtained. The maximum quantity of total potassium and the minimum dry weight were found when the wastes were added in 10 days interval.. |
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