白线蚓对蚯蚓处理城市污泥的影响

蚯蚓处理污泥反应器中,常伴大量的白色线蚓(寡毛纲、线蚓科).因此,本文以蚯蚓处理城市污泥为研究对象,初步探讨了白线蚓(Enchytraeus Spp.)接种密度对赤子爱胜蚓(Eisena fetida)处理城市污泥的影响.结果表明,白线蚓的密度显著影响了蚯蚓堆肥后产物的物理化学性质和蚯蚓的生物量.白线蚓接种密度与蚯蚓堆肥产物的pH值、电导率(EC)、总氮(TN)呈负相关;与其总有机碳(TOC)、有效磷(AP)、重金属Cu、Zn、Pb、Cr及Cd的含量呈正相关.同时较高的白线蚓接种密度显著降低了蚯蚓的生长率,但蚯蚓的卵数未受显著影响.由此可知,蚯蚓和白线蚓在反应器中存在食物链竞争关系.本研究建议对蚯蚓处理污泥反应器中的白线蚓采取一定的控制措施.

Effects of enchytraeids on vermicomposting of sewage sludge

A large number of enchytraeids are often propagated in vermicomposting reactor during recycling of sewage sludge, which may affect the performance of vermicomposting by earthworms. Therefore, this study aims to investigate the effects of different densities of enchytraeids inoculated on the vermicomposting for treating dewatered sludge. The results show that the properties of final vermicomposting products and the biomass of earthworms were strongly influenced by the densities of enchytraeids. The increasing population of enchytraeids had a negative correlation with pH, electrical conductivity (EC), total nitrogen (TN) of the vermicompost, while had a positive correlation with total organic carbon (TOC), available P and heavy metals (Cu, Zn, Pb, Cr and Cd) of the end products. And also, the higher density of enchytraeids significantly reduced the growth of earthworms. However, for the cocoon number of earthworms, no significant effect was recorded. Such finding reveals that the relationship of food chain competition between earthworms and enchytraeidae existed, causing the negative effect on earthworms. Hence, it is suggested that some control measures should be taken for the enchytraeids in the vermicomposting reactor of sewage sludge.