Study Of Sewage Sludge Compost Used In Seedling-raising And Soilless Culture Of Petunia Hybrida

Sewage sludge contains large amounts of organic compounds, phosphorus, nitrogen and other nutrients and pathogens.It would cause serrious pollution to the environment if they were not be dealt with. Application on the cultivation of garden plant is a reasonable methods for sewage sludge compost which should be promoted.In this study, dewatered sewage sludge from Nanchang Qingshan Lake Sewage sludge Treatment Co., Ltd, sawdust and cinder were mixed at different volume ratio. Through the reseach of the physical and chemical properties of compost composed with different materials, explored the application of sewage sludge composting in seedling-raising and soilless culture of Petunia hybrida,the nutrient uptake and distribution of Petunia hybrida,its aim is to resolve some problem in the utilization of sewage sludge compost in theory.The main results were as follows:The changes of physical and chemical properties of compost consisted with different volume ratio of materials showed that, the nutrient contents which could be effectivily uptaked by plants increased after composting, and the content of heavy metal was decreased as the cinder had some passivation effects on heavy metals in sewage sludge. Compost mixed with sewage sludge and sawdust, cinder was more efficient than signal sewage sludge composting or compost mixed with sewage sludge and sawdust or compost mixed with sewage sludge and cinder. As far as the physical and chemical properties of compost was concerned, compost mixed with sewage sludge, sawdust and cinder 3:1:1 showed the best efficient on plant.The heavy metal content in sewage sludge was in the standard range,but the low pH and high EC values of the compost were the main deficiency on its agricultural applying.The research of the retting mature sludge extracts and sewage sludge compost on seeding-raising of Petunia hybrida showed that retting mature sludge extracts on seed germination, seedling growth inhibition. Inhibited the more obvious the higher the concentration.Mainly due to excessive retting mature sludge extracts'EC values over the range suitable for plant growth. Sewage sludge compost decreased seed germination rate and seedling survival rate of Petunia hybrida,inhibited the growth of Petunia hybrida seedlings. Sewage sludge compost acidic pH, high EC values is the possible reason.With different proportions of sewage sludge compost and perlite mixture 3:1 by volume as substrate of Petunia hybrida. The effect of sewage sludge compost on growth and development of Petunia hybrida was researched,the result showed that the best formulas of substrate for Petunia hybrida is treatment 1 (sludge:sawdust:cinder=3:1:1)3: perlitel and treatment 5 (sludge:sawdust=3:2) 3:perlite1.Petunia hybrida nutrient absorption and distribution of study have shown that petunia hybrida on N, P, K absorption varies in different growth stages. K is much larger than the absorption of N, P uptake. During vegetative stage, N, P, K were higher in the leaves, after N, P, K content increased in the flowers at the reproductive stage, N, P, K absorption assigned to the growth center.