Organic Characteristics And Source Analysis Of Suspended Solids In Apparently Polluted Water

At present,most of the functions of urban water bodies have been transformed into landscape functions.With the acceleration of China’s economic growth,a large number of people have entered cities to work and live,and the urban population has rapidly increased.The weak awareness of water resources protection of urban residents and the fragility of urban water bodies have caused the appearance of poor quality of urban water bodies due to the influence of external pollutants to become more serious,and the landscape functions of urban water bodies have also been affected.With serious damage,the protection of urban water bodies is imminent.Based on the previous research of the research team,the suspended matter is the main cause of the apparent pollution of the water body.From the perspective of the particle size distribution of the suspended matter and the flow velocity acting on the suspended matter in the water body,we can explain its impact on the apparent pollution.Changes in the components of suspended solids in different types of water bodies may lead to different appearances of water bodies,and the components that are prone to changes are mainly organic components.Suspended particulate matter is a very complex organic-inorganic complex,so it is meaningful to explore the organic characteristics of the suspended matter surface and its source.This study is based on the flow cytometry analysis method to study the organic characteristics of suspended solids in different types of water bodies.According to the previous classification standards of water bodies,the water bodies are classified.The urban landscape water bodies of Suzhou City are used as the research object,and the suspension is analyzed by scanning electron microscopy.Quantify the suspended solids by measuring the concentration of suspended solids,and finally combine the FITC organic matter content,heterotrophic bacteria content,and phytoplankton content obtained by flow cytometry to explore the suspended solids in different types of water.Organic characteristics,select typical rivers to analyze the change history of the organic characteristics of suspended solids,and combine the organic C/N ratio of particulate matter to study the organic characteristics and sources of suspended solids in water.After a series of experimental studies,the main conclusions are as follows:（1）According to the results of scanning electron microscopy,the material forms of suspended solids in urban landscape waters are mainly divided into the following types:mineral particles,flocs,and monomer algae.The content of flocs in organic-dominant waters is as high as 30%～60%,the inorganic dominant type is mainly composed of clay mineral particles and mineral particles wrapped with organic matter,that is,an organic-inorganic complex.The nutrient-oriented water body is mainly composed of monomeric algae.The mixed type is similar to the inorganic dominated type,the only difference is that the mixed type water has a higher proportion of flocs particles.（2）During the study period,the characteristics of the total amount of suspended solids in different polluted water bodies were as follows:inorganic-dominated water had the highest TSS content,with an average value of 67.2 mg·L^-1,and nutrient-dominated TSS had the lowest content,with an average value of 7.6 mg·L^-1,the average TSS content of organic-dominated water is 32.7 mg·L^-1,and the average content of mixed TSS is 24.2 mg·L^-1.The proportion of OSS/TSS in different types of water bodies is organically dominated>nutrition dominated>mixed type>inorganic dominated.The average values are 77%,70.8%,41.2%,and 19.8%,indicating that there is suspension in Suzhou landscape waters.The main substances are mainly organic components.（3）Using flow cytometry analysis,the particles in the urban landscape water that can be FITC dye accounted for 65%to 92%of the total particles,indicating that the suspended particles in the water rarely exist alone,and it also shows that the suspended particles in the water body rarely exist alone.The surface is covered by abundant protein organic matter,protein-containing bacteria,phytoplankton.（3）The distribution of FITC organic matter in different types of water bodies is:inorganic-dominated type>organic-dominated type>mixed type>nutrient-dominated type,which is highly correlated with the content of suspended solids;the distribution characteristics of heterotrophic bacteria in different types of water bodies are mainly It is organic-dominated>inorganic-dominated>mixed>nutrient-dominated,which is related to the degree of organic pollution in the water body and the concentration of suspended solids;the phytoplankton content is similar to the distribution of heterotrophic bacteria,indicating that there is a certain degree of phytoplankton and heterotrophic bacteria.Correlation.（4）Based on the influence of environmental factors on the organic characteristics of suspended solids based on factor analysis,it can be seen that the high content of FITC in inorganic-dominated water is mainly due to the higher concentration of suspended solids.The content of each component in organic-dominated water It is mainly related to the DOC,Chl-a and nitrogen and phosphorus nutrition content in the water body.The content of each component in the nutrient-oriented water body is mainly positively correlated with Chl-a,and the content of each component of the suspended matter in the mixed water body is positively correlated with the concentration of the suspended matter,Chl-a.（5）Source analysis of suspended solids in typical rivers1.The average flow velocity of the Free Village Bridge is 0.04 m/s,which is mainly nutrient-oriented,but it is easy to be polluted by external sources to change the type of water body.According to the change in the content of FITC organic matter in the suspended solids,combined with the particulate C/N ratio Analyzing the source of suspended matter,study periods 7,8,and 9 correspond to the early,middle and late periods of the flood season.The suspended matter in the middle of the flood season showed a heterogeneous type,with a C/N of about 13.3,mainly due to the influence of surface runoff from the source surface.The source is mainly self-derived,with a C/N of about 8,and the main source is from authigenic algae propagation.The C/N ratio of suspended matter in December was 17.04,showing a very strong heterogeneous type,which may be related to the surrounding road construction.2.The average flow velocity of Hualien Road and Bridge is 0.32 m/s,which is a mixed water body.There is no obvious external source input in the water body of Hualien Road and Bridge.During the study period,the overall C/N ratio of Hualien Road and Bridge was in the range of 7.08-11.79.The changes in FITC organic matter content showed a good correlation with it.The heterogeneity of suspended solids is mainly concentrated in the middle of the flood season in August,and the C/N ratio is about 11.28.It is mainly due to the external input caused by rainfall.On the whole,it can be seen that the organic characteristics of the surface of the particulate matter in the water body are mainly manifested from the source.Sexuality stems from the growth of algae and the re-release of organic pollutants from the bottom mud.