Temporal And Spatial Variation Of The Yellow Ditch Area Of Bosten Lake Basin Salinity, Nitrogen And Phosphorus

In recent years,with the rapid social and economic development, production and development ofindustrial and agricultural activities to increase strength, coupled with the irrational exploitation of waterresources and the rapid increase in population, serious damage to the ecological environment of theBosten Lake Basin.Salty water and eutrophication is the main type of making the environment worse.Agricultural non-point source water pollution problems due to environmental issues have becomeincreasingly prominent, while the level of point source pollution control relative increase, non-point sourcepollution, especially heavy use of fertilizers and pesticides caused by the people’s attention.In this paper, combined with the actual situation,based on the domestic and foreign research onnon-point source pollution,the typical farmland of Bosten Lake Basin as an example, Through a series ofinvestigations,experiments, analysis, research the temporal and spatial distribution characteristics of plotssalinity,nitrogen and phosphorus in the field and the drainage ditch after the winter irrigation,discusses thesource of agricultural non-point source pollutants and internal relations.To provide a theoretical basis forthe control and prevention the non-point source pollution of salinity and nutrients in the Bosten LakeBasin, and has important significance to improve the ecological environment of the river basin. The mainresearch contents and results are as follows:（1）After winter irrigation,the layers of farmland soil salinity and TP concentrations showed a risingtrend over time,while the concentration of NH+-4-N,NO3-N and TN decrease with time. Along the depthdirection,soil salinity, NO-3-N and TN concentration increased gradually along the vertical direction,thevertical NH+4-N concentration did not change significantly,TP tends to decrease along the depthdirection.Compared nitrogen, phosphorus, salt concentration before and after the winter irrigation, theconcentration of the pollutants in the soil before filling were significantly greater than after winterirrigation,because of the irrigation water flushing, farmland nutrients enter the Bosten Lake.（2）Farmland along the vertical between soil salinity and nitrogen, phosphorus concentrationinterrelated impact.Through the analysis of soil salinity monitoring data after irrigation,20-40cm and40-60cm layer of soil salt concentrations were significantly correlated. And along the vertical direction ofsoil TN concentration correlation decreased.0-20cm and20-40cm layer of soil has high correlationbetween the concentration of TP.No obvious correlation between the concentration of NH+4-N and TN insoil after irrigation,TN and NO-3-N concentration has a high correlation,TN mainly as NO-3-N.（3）Drainage water salt concentration versus time showed a decreasing trend,Changes in nitrogen,phosphorus with time large fluctuations in the initial and then level off.Salt, NH+4-N, NO-3-N, TN and TP inthe horizontal direction from the inlet to the outlet of the drainage ditche showed a slow decreasing trend,this shows that interception of drainage ditches for pollutants has a certain effect.（4）Drain sediment salt concentration increased over time,and the sediment concentrations ofnitrogen and phosphorus more complex over time, at the entrance showed a decreasing trend over time.Inthe horizontal direction,since the accumulation of salt and nitrogen, phosphorus,from the gutter to the nextexit of the inlet sediment salt,NH+4-N, NO-3-N, TN and TP concentrations along the trend showed a slowrise.（5）By analyzing the concentration of pollutant drainage ditch in the water and sediment related relation, the salt concentration in drainage water and sediment showed highly significant negativecorrelation, the concentration of TN was a weak negative correlation, significantly positive correlation withthe concentration of TP.The concentration of salt and TP in drain water inlet and outlet is closed.（6）The relationship between soil salt concentration and drain sediment closely that significantcorrelations. The concentration of TN is related to the soil and drain the sediment, and the content of TPsoil and drain sediment correlation is weak.