Study On The Remediation Of Contaminated Water Body By Coupled Microorganisms Of Aquatic Plants

In recent years,a large amount of domestic sewage and industrial wastewater have caused serious pollution in China's water bodies,and the status of water pollution is not optimistic.In the treatment of sewage,the combined restoration technology of plants and microorganisms has gradually been applied.However,there is not much discussion about whether there is a mechanism of action.In order to make a preliminary study on the mechanism of action in the combined restoration of plant microorganisms,this study sets the The static dynamic experiment of the water bacteria capsule not only evaluated the water purification effect of the plant water purifying bacteria capsule,but also researched and discussed the relationship existing between the plant microorganisms combined water purification process.The main research results are as follows:(1)Water purification bacteria-embedded solid capsules showed good performance in water purification experiment.On about the 7th day,the removal rate of ammonia nitrogen reached 60%.The optimal dosage of water purification bacteria-embedded solid capsules was determined as 20 g.Iris tectorum Maxim.was screened as experimental plant in this experiment.Iris tectorum Maxim.presented not only good environmental adaptability,but also good effect in the water purification experiment combined with water purification bacteria-embedded solid capsules.During the experiment,the removal rate of ammonia nitrogen reached 72%,and the removal rate of TN reached 40%,which were far superior to other groups.(2)By comparing the low-concentration ammonia nitrogen dynamic simulation experiment with the high-concentration ammonia nitrogen dynamic simulation experiment,it is found that increasing dissolved oxygen may contribute to the removal of ammonia nitrogen,but it is not conducive to the removal of TN.At the same time,nitrification dominates in the simulated dynamic experiment.(3)High-throughput dynamic water purification results revealed a total of 52 bacterial phyla,120 bacterial classes,267 bacterial orders,524 bacterial families and 1,292 bacterial genera.Proteobacteria,Bacteroidetes,Firmicutes,Actinomycetes and Cyanobacteria occupied a dominant position in samples.Moreover,Proteobacteria was the most dominant strain among all samples.Ammonia-oxidizing bacteria in samples belonged to 10 phyla,3 classes,5 orders,5 families and 9 genera.Proteobacteria and partial unclassified bacteria were the most dominant strains,with a proportion of 98.3%.Denitrifying bacteria belonged to 4 phyla,7 classes,10 orders,10 families and 12 genera.Among them,over 96.1%were mainly distributed in Proteobacteria and unclassified bacteria.The results of typical correlation analysis(RDA)showed that the relationship between environmental factors and water purification bacteria samples was ammonia nitrogen>TN>COD>DO,which was the most relevant for Nirs functional microorganisms,and the most important for ammonia nitrogen in Amob functional microorganisms.(4)The combination of plants and bacteria had an effect on microbial diversity index(Chao1 index Shannon index)in water.Experimental results showed a highest Chao1 index and Shannon index in the plant-microorganism combination group.The microbial Chao1 index of water samples increased by adding plants,while diversity index showed no obvious increase in the experimental group with only water purification bacteria-embedded solid capsules added.As the experiment progressed,the abundance index of the microorganisms in the water body of the combined group(YWB)gradually increased in two different concentrations of ammonia nitrogen,and the other groups in the comparison experiment also belonged to higher values,and the combined group(YWB)net in the experiment.The water effect is always the best,indicating that there are more microbial species in the water body of the plant and microorganism.