The Effect Of Papermill Pollution On Daling River Sediment Bacterial Community

Papermaking wastewater of Jincheng Paper Co.,Ltd is the major pollution of Daling River. There is vast sulfate in the wastewater, as sulfur is used in papermaking process. Actually, it does not directly do harm to the River, therefore it didn’t attract much attention in the past. The sulphate is easily to accumulate in the sediment because it is stable in the natural condition, however its accumulation may affect the entire ecosystem. SRB can produce large amounts of sulfides such as thio sulfide and other toxic substances, including toxic odor H2S by sulfate reduction in the natural environment, and eventually generating serious pollution. Meanwhile, the community of SOB will be changed. Therefore, it is necessary to study the community of SRB and SOB in the sediment polluted by papermaking wastewater.The sulfur metabolism genes of SRB and SOB were studied in our work. We utilized DGGE to study the effect of sulfur pollution on the bacterial communities of Daling River. We selected12sampling points along Daling River, and studied the bacterial communities of the sediment samples for three consecutive years.The results of this research are as follows:1. There was lots of sulfate in the papermaking wastewater of Jincheng Paper Co.,Ltd, and the sulfate concentration in the sediment of the sewage area was much higher than other sampling sites.2. The16srDNA fingerprint of three years showed that the microbial species were abundant. There was high diversity index and low bacterial community similarity in sewage area compared with other sediment samples. We also found that the bacterial communities of the downstream region were relatively similar.3. The apr DGGE profiles indicated that there were few species of bacteria related to sulfur metabolism. But the species of sulfur bacteria in the sewage area were more abundant than other sites. It showed that there was more active sulfur metabolism in the sewage area than other sites, which is closely associated with high level of sulfate.4. The results of sequencing showed that most of the bacteria are similar to SRB, and lots of them are similar to Desulfobulbus which is an incomplete oxidation SRB, and a few are similar to Desulfobacterium which is a complete oxidation SRB, while the main SOB is the chromatiaceae Thiococcus.