Spatio-temporal Differentiation Charactertistics Of Conventional Water Quality Parameters For The Chemical Factory Reach Of Ancient Canal In Yangzhou City

To reveal the water quality change of Yangzhou agrochemical factory's upstream and downstream of ancient canal,choosing the 4 sections(Sec.1,Sec.2,Sec.3,Sec.4)of Yangzhou agrochemical factory's upstream and downstream of ancient canal to develop the monitor for the WT,pH,DO,EC,and TDS;Based on the observation results of the conventional water quality parameters from October 2015 to July 2017 of the four observed sections agrochemical factory of ancient canal in Yangzhou,using correlation coefficient method,single factor analysis method,coefficient of variation coefficient and multiple linear regression coefficient to analyze the observed results,evaluating the effect of chemical plant drainage on the water quality of the ancient canal.The main conclusions are as follows:(1)The drainage of chemical plants led to the increase of WT in local whole section of the ancient canal,the decrease in DO,the obvious change of pH,and the increase of EC and TDS.Both upstream and downstream sections'(Sec.1 and the Sec.2)WT,pH,DO,EC and TDS corresponding observation sequence value's correlation coefficient were 0.99,0.91,0.90,0.88 and 0.88,showing two section observation sequence of each water quality parameter had significant correlation.(2)During the period of observation from October 2015 to May 2016 and December 2016 to April 2017,Sec.1 DO met the ancient canal water function area water quality goal,in other time,DO did not satisfy the water function area water quality goal;In the observation period from December 2015 to March 2015 and from January 2016 to March 2016,Sec.2's dissolved oxygen concentration met its water function area water quality goal,in the other time,did not meet their water function area water quality goal;And the water quality of Sec.2 is worse than that of the Sec.1.(3)In WT,DO,pH,EC,and the observation sequence of TDS value of coefficient of variation,the amplitude of fluctuation of DO was the biggest,the fluctuation range of pH was the smallest,the variation process of two observed sections of EC and TDS was similar,and Sec.2 had larger variation degree;The variation degree of the same section EC and TDS was the same.(4)Analyzing the Sec.1,Sec.2 DO and pH,WT by multivariate linear regression,Sec.1's pH and Do's standard coefficient were 0.514 and-0.482,showing that the main factors affecting the DO were pH and WT,the pH was the main factor influencing the DO.The standard coefficients of Sec.2 pH and DO were 0.500 and-0.388 respectively,indicating that the main factors affecting DO were pH and WT,the pH was the most important factor affecting DO.(5)The intersection of ancient canal and Andunriver was equipped with an Andun gate.The gate opens every 1?2 months,and the rest of the time there is not exchanged water with the ancient canal.Therefore,the impact of the Andun river on the water quality of the ancient canal can be ignored.In the intersection place of ancient canal and the new town river,the ancient canal's water flow direction towards the new town river,so the influence of the new town river on the water quality of the ancient canal can be excluded.The results of the study expects to provide part of basic data for the measures adopted of improving the water quality of Yangzhou ancient canal and the water environment research,providing reference of methods to the research of urban river water quality.