Preliminary Study On The Morphology And Spatial Distribution Of Phosphorus In Sediments Of Daya Bay And The Restoration Of Pond Sediments

Phosphorus is the main limiting factor for eutrophication of water bodies and has an important impact on the primary productivity and nutritional status of water systems.Compared with phosphorus in water,the potential phosphorus source in the sediment is more abundant.At the same time,it also acts as a buffer for the phosphorus content in the water.The study of the release of endogenous phosphorus from sediments can be used to understand the cycling and regeneration mechanisms of phosphorus in water environments,as well as to evaluate the exchangeability and bioavailability of phosphorus in sediments.At the same time,the clean,high quality substrate can act as a buffer when the water body is polluted by the outside,slowing the eutrophication of the water.The SEDEX method was used to extract the phosphorus from the sediments of Daya Bay.The results showed that the TP was 209.36-525.13?g/g,the Abs-P content was 1.01-8.36%,and the Fe-P content was 2.88-8.88%.The content of Ca-P accounts for 4.26-17.93%,and the content of De-P accounts for 13.35-61.46%.De-P is the main form of IP,and this part is difficult to participate in the change of phosphorus content in the ocean.Human activities have a great interference on the degree of eutrophication in the Daya Bay.The OP,TN and TOC are significantly correlated with each other(P<0.01),and the ratio of TOC/OP in the surface sediments of Daya Bay is much larger than 106,indicating that the source is The impact of nutrients in the sea is great.KHSO₅ effectively converts the black viscous sediment into a yellowish brownish thinner,and as the concentration of use increases,the total phosphorus content in the sediment decreases,and the phosphorus content of each form also It showed a downward trend with the increase of concentration,indicating that KHSO₅ has certain effects in decomposing organic pollutants.Bacillus subtilis can tolerate various inhibitory substrates and harsh environments.In this experiment,the ammonia nitrogen content and nitrite nitrogen content in the water added with Bacillus subtilis were significantly decreased,and the p H of the experimental group was significantly different from that of the control group(P<0.05),the high dose of the experimental group can significantly reduce the number of Vibrio in the water.In the results of this experiment,there was no significant difference in the content of different forms of phosphorus in the sediment compared with the control group,indicating that the addition of Bacillus subtilis had no effect on the phosphorus in the sediment.After adding Lactobacillus,the number of Vibrio in the aquaculture water of the experimental group was significantly lower than that of the control group,indicating that the Lactobacillus had a strong effect in inhibiting the growth of Vibrio.However,in the experimental group to which lactic acid bacteria were added,the contents of ammonia nitrogen and nitrite nitrogen were higher than those in the experimental group.In the results of this experiment,there was no significant difference in the content of different forms of phosphorus in the sediment compared with the control group,indicating that the addition of Lactobacillus had no effect on the phosphorus in the sediment.In summary,the water environment in Daya Bay is affected by human activities,and there is a trend of eutrophication.The management of the environment cannot be delayed.KHSO₄ has obvious effects in improving sediment pollution.At the same time,Bacillus subtilis has a great effect in helping to improve water quality.Lactobacillus can better inhibit the number of Vibrio in aquaculture water.