复合垂直流人工湿地中基质生物膜的特性

从基质生物膜量、生物膜厚度和脱氢酶活性等方面研究了以复合垂直流人工湿地中基质颗粒作为附着生长载体的生物膜的特性。结果表明，复合垂直流人工湿地中，基质生物膜的形成时间为40~60 d。进水水质不同,基质生物膜的形成时间有差异，进水中相对高的营养水平有利于基质生物膜的积累，60 d内形成的稳定生物膜量相差1.59倍；生物膜活性也较大，平均相差1.5倍。不同发育程度的生物膜表现出的活性不同，最佳活性厚度为150 um。人工湿地中不同层次基质生物膜厚度差异显著，最表层0~5 cm层次基质生物膜厚度2~3倍于10 cm以下层次，为最佳活性厚度的3~4倍，其生物膜的过量积累不仅不利于处理效率的提高，且易造成人工湿地的堵塞。

BIOFILM CHARACTERISTICS OF THE SUBSTRATE IN INTEGRATED VERTICAL-FLOW CONSTRUCTED WETLAND

The biomass,thickness and activity of the biofilm in substrate in integrated vertical-flow constructed wetland were studied.The formation time of biofilms varied from 40 to 60 days with the quality of influent water.The biofilms with high trophic level in influent accumulated rapidly,the steady biomass and activity of biofilms were 1.59 and 1.5 times higher.The activity of biofilms with various thicknesses was different,and the optimum thickness was 150 um.The biofilm thickness in different layers of the substrate was dissimilar,the thickest biofilm was in the outmost surface(0~5 cm) of the substrate,being 2~3 times of other layers and 3~4 times of the optimum thickness.Excessive biofilm accumulation was not in favor of improvement of treatment efficiency and prone to cause clog of constructed wetland.