Bio-abiotic Uptake Potential And Release Risk Of Phosphorus In Suburban Stream Streams Under Human Disturbing

The urban-rural interlaced belt is a kind of spatial transitional area between urban built-up area and rural area.Combining the advantages of urban and rural economic systems.At the same time,it is also a region where the problems of ecological environment are prominent and the contradictions are the most acute.Correspondingly,the characteristics of river water pollution in the area of this area are greatly influenced by human disturbance.Biotic and abiotic uptake of phosphorus in sediments is a significant research topic in the field of water pollution control and water environmental protection,and is also a hot research topic in current Environmental Science and Engineering.In this paper,by observing the bottom quality changes of stream channel under three kinds of human disturbances in interlaced urban and rural areas in Hefei.Samplesofoverlyingwaterandsurfacesedimentarecollected monthly.Ecological conditions of water environment of stream channels and speciation analysis of phosphorus was carried out accordingly,and to make assessment of the ecological potential of streams and the risk of phosphorous release from the bottom of the stream,and to make qualitative and quantitative analysis of biotic/abiotic uptake of phosphorous base.The main research results were outlined as follows:?1?The water quality of the stream in Modian is basically weak alkaline.Only in the case of natural canal section,the evaluation of water ecological function reached the standard,while the other cases were poor five categories and black odor.ThecontentofTPinthebottomofthestreamchannelis127.748mg·kg^-11232.832mg·kg^-1,and the assessment of total phosphorus pollution in the case of sewage outlet adjacent to the sewage outlet is high risk,and the rest of the situation is of lower risk.?2?Study on the canal stream of fresh benthic sediments biotic and abiotic uptake potential of the mean value of 0.950?g??g?h?^-1,2.461?g??g?h?^-1,benthic dry biotic and abiotic uptake potential mean value of 0.159?g??g?h?^-1,0.921?g??g?h?^-1.In general,the abiotic uptake potential is higher than that of biotic uptake potential,and the biotic and abiotic uptake potential of fresh benthic sediments is much higher than that of biotic uptake potential.?3?The contribution rate of benthic sediments phosphorus is much lower than the contribution rate of abiotic uptake,both fresh and dry samples.The contribution rate of abiotic uptake of wind dry samples is about 80%,and the contribution rate of biotic uptake is about 20%.?4?No.3 sampling point adjacent to a sewage outlet,the biotic and abiotic uptake potential of benthic sediments phosphorus is higher than that of other points in each season.It shows that the more serious the water pollution is,the greater the phosphorus uptake potential of benthic sediments is.The difference between the two indicators was significant in the three cases.It is also shown that human disturbance brings more complexity to the stream benthic sediments environment.?5?The benthic sediments PSI value of the natural canal section of the stream is the highest in 3 cases,the mean of 32.150?mg?L?·?100g·umol?^-1,the lowest soil erosion,the average is 25.379?mg?L?·?100g·umol?^-1.In season,the points are basically characterized by the peak value in summer.The characteristics of phosphorus release risk assessed by PSI,DPS and ERI are basically consistent,and the levels of corresponding phosphorus release risk were as follows:discharge section>soil erosion section>natural canal section.