Sludge bulking leads to loss of balance in sludge microecosystem, change in microbial community structure and filamentous bacterium domination.

• 指出丝状菌污泥膨胀的实质是活性污泥微生态系统平衡失调，微生物群落结构与功能发生变化，丝状菌种群代替菌胶团菌群成为优势种；