BEIJING( REUTERS)-China's eastern port city Qingdao is experiencing the worst ever algae infestation in the region, with more than 1, 700sq km of coastal area blanketed by harmful green seaweed, also known as" green tide". Qingdao has suffered from algae for 15 years.... It normally appears from late spring and lasts for three to four months, damaging the local marine ecosystem as algae take oxygen from other organisms and churn out toxic odours while decaying. More than 1 million tonnes of alg