A Record-setting of Cyanobacterial Bloom in 2017 in Lake Taihu, China

Session: 52. - Climate Interactions with Large Lakes? Physical Systems

Boqiang Qin, Nanjing Institute of Geography & Limnology, [email protected]

Abstract

Lake Taihu is a large shallow and eutrophic lake. It has long suffered from the eutrophication and HABs persistence, which had resulted in the drinking water crisis in Wuxi in May 2007. Since that time, intensive lake restoration with various measures have been implemented in this lake, including the construction of wastewater collection pipeline system and treatment plants, wetland restoration, sediment dredging and water diversion from Yangtze River for flushing. Monitoring program found that there is little abatement of cyanobacterial bloom and decrease in nutrient loading. The reason is attributed to low nutrient removal efficiency of wastewater treatment and less measures taken aiming at the non-point pollution control. More importantly, the climate change, i.e. increase in the water temperature in winter and spring and decrease in wind speed, exacerbated the cyanobacteria bloom persistent throughout the all year round. Nutrient enrichment and climate warming are the results of the record-setting of cyanobacterial bloom in 2017. Intensive cyanobacterial bloom occurred earlier and long persistent, however, caused the increase in pH frequently due to the enhanced photosynthesis, which further promoted the phosphate releasing from sediment and extending the water quality deterioration and cyanobacteria bloom persistence.

1. Keyword
global warming

2. Keyword
eutrophication

3. Keyword
water quality

4. Additional Keyword
cyanobacteria bloom