The reduction action of anaerobic sulfate plays an important role in the metabolism of organic matter in the water, the release of endogenous phosphorous in sediments and the production of blackening matter. Previous researches show that the reduction action of anaerobic sulfate in water columns mainly takes place in ocean hypoxia zones and naturally stratified deep lakes. It is normally believed that the reduction action of anaerobic sulfate is hard to constantly take place in shallow lakes.   

Doctor Chen Mosheng and other researchers of Jiang Helong Research Group of Nanjing Institute of Geography and Limnology cooperate with the Institute of Soil Science and the researching team of the University of Oklahoma in the United States. By carrying out the simulating experiment on continuous flow, they found that during the falling and dying process of water-blooming cyanobacteria, the current sulfate ion concentration (about 100 mg L-1) in Taihu Lake can maintain the continuous reduction action of the anaerobic sulfate in water columns. The natural decomposition of cyanobacteria biomass causes the dissolvable sulfide concentration in water columns to be up to 5.90 mg L-1. The reaction between highly concentrated dissolvable sulfide and ferrous iron can produce large quantity of blackening matter ferrous sulfide in the water and sediments of 0-1 cm thick at the surface of the water. In addition, during the decomposition process of water-blooming cyanobacteria, the reduction action of sulfate ion in the water promotes the phosphorous combined with iron to be released from sediments, worsening the lake eutrophication. The research shows that the change of the sulfate concentrations in the water shall be noticed during the management of eutrophic lakes.

The above outcome “Increasing sulfate concentrations result in higher sulfide production and phosphorous mobilization in a shallow eutrophic freshwater lake” has been published in major journals of environmental science Water Research. This research has received funds including National Science Foundation of China.

Link: http://www.sciencedirect.com/science/article/pii/S0043135416301579