Research On Space And Time Change Rule And Influence Factor Of NO₂～--N Content In Breeding Sea Area Of Tang Dao Gulf

In recent years, our country sea area breeding way is developing to the high intensity,water contamination could seriously affect the sustainable development of aquatic productbreeding. Accumulation phenomenon of the nutritive elements in the sea and deposition ofbreeding area is becoming more and more serious. Research is insufficient, because thevelocity is rapid that NO₂^--N returns to the nitrogen gaseous oxide compound. People haveneglected frequently the fact that NO₂^--N transformation in the short-term can engender ecologytoxicology influence to the biological individual. NO₂^--N can transform the hemoglobin of theblood in into the meta hemoglobin, and cannot again combination with the oxygen, causing theparalysis of oxygen transportation function, therefore NO₂^--N accumulates of low quantitypossibly affect the survival of aquatic biological.Pick earth sample of the sea water surface layer, the sea water basement and depositionbottom in breeding sea area of Tang Dao gulf in spring, summer, autumn and winter. Based inlaboratory analysis, this paper researches the space and time change of the main physics andchemistry index?ï¿ nitrogen content of kinds of shapes, and attributes the space and timedistribution rule of NO₂^--N. Indicate quantitatively the influence of various environment factorto NO₂^--N content by correlation and the regression analysis to the obtained data exerting theSPSS statistics software.The research indicates:(1) The water quality of breeding sea area in Tang Dao is weaker than that of comparisonspot, but the pollution degree is low, lower than the two levels of national standards.(2) The NO₂^--N -content of Tang Dao gulf appears obvious accumulation in the autumn, andthe mean value has achieved even higher than 20|ìg/L, but content of other season is quite low.The NO₂^--N content of the superficial water is higher than the basement water generally. In thedeposit the NO₂^--N content is quite low, and the difference of four seasons is quite small.(3) The NO₂^--N content have prominent relevance with environment factor of water. NO₂^--N?ï¿ NH4+-N of superficial water has achieved remarkable relevance with IP (p<0.01), with COD, DO,the salinity, pH and the transparency have achieved the remarkable inverse correlation (p<0.01),and it is also strong with the chlorophyll relevance (p<0.05). In the first floor sea water NO2--Nand NH4+-N, NH4+-N, IN and IP have achieved remarkable relevance (p<0.01), while COD, pH, DOand the salinity have achieved remarkable inverse correlation (p<0.01), with chlorophyllrelevance also very strong (p<0.05), in the deposit NO2--N and the organic matter and IN haveachieved remarkable relevance (p<0.01), and it is also strong with the NO3--N relevance (p<0.05).(4)The thesis adopts the regression analysis, knowing that in the surface layer sea waterCOD, DO and the salinity have an enormous influence on the dependent variable NO2--N. In firstfloor sea water IN, NH4+-N and NO3--N?ˉs influence on dependent variable NO2--N is the biggest,while the organic confrontation has a overwhelming influence on the dependent variable NO2--Nin the deposit.Having obtained in the sea water and the deposit according to the regression analysis resultthe NO2--N standardization regression equation, the thesis indicates various environment factorsby the quota to the water body in the NO2--N content influence, for the further study of the NO2--Npollution in the breeds of the sea area water body.