Effects Of Humic Acid On The Growth And Reproduction Of Earthworm And The Contents Of Cu And Zn In Compost Products

Using vermicomposting to treat livestock manure is a commonly used way of resource utilization.Vermicomposting is a kind of high quality organic fertilizer.At the same time,adult earthworm can also be used as bait to enter the fishing market.In this paper,the treatment of different livestock manure and organic waste by earthworm,the effect of humic acid on the growth and reproduction of earthworm and the effect of humic acid on the content of Cu and Zn in earthworm body and compost products were studied in order to provide some reference for the popularization and application of vermicomposting.The main research contents and results are as follows.1 Study on the treatment of different livestock manure and organic waste by earthwormPig manure,cow manure and sweet potato sludge were treated with earthworm to study the growth and reproduction of earthworm in different raw materials and the physicochemical properties of earthworm manure.The results showed that the amount of cocoon produced by earthworm in pig manure was more than that in cow manure,and the earthworm in cow manure had the largest earthworm weight at the end of the experiment.The p H value of each raw material compost product decreased and approached neutrality,the organic carbon content decreased,and the total nitrogen,phosphorus,potassium and available nutrients content increased significantly(P < 0.05).2 Effect of humic acid on the growth and reproduction of earthwormHumic acid was used as an additive for pig manure-earthworm compost to explore the effect of humic acid on the weight gain and cocoon production of earthworms.Studies have found that humic acid has a promoting effect on the weight gain and cocoon production of earthworms.When the humic acid content was 2 % of the dry weight of pig manure,the contents of total nitrogen,total potassium,available nitrogen,available phosphorus and available potassium in pig manure vermicomposting increased significantly(P < 0.05).3 Effects of humic acid on copper and zinc contents in earthworm and compost productsHumic acid was added to pig manure compost and natural compost to study the effect of humic acid on the copper and zinc content of worm and compost products.The results show that the addition of humic acid can weaken the accumulation of heavy metals in the compost and reduce the content of copper and zinc in earthworms.Both vermicomposting and natural compost can significantly increase the content of copper and zinc in the compost product(P <0.05);Vermicomposting could significantly reduce the contents of available copper and zinc in compost products(P < 0.05),but adding humic acid to vermicomposting did not further reduce the contents of available copper and zinc.In conclusion,the growth law of earthworm in different livestock and poultry feces and organic wastes was explored.Meanwhile,the weight and cocoon production of earthworms in pig manure were increased by humic acid,and the accumulation of Cu and Zn in earthworms was reduced,which provided some scientific basis for vermicomposting.