Study On Zoology Characteristic Of Nitrifying Bacteria And Nitrification In Yellow River Delta

In recent years,With the increasing of population and the developing of agriculture and cultivation industry,the nitrogen pollution tointensify,and the red tide phenomenon occurrenced frequently in shore sea area. It forms serious pollution for ocean environment. Therefore, the biology rehabilitate technic about inorganic nitrogen contamination is becoming one of the important research field in current ocean pollution disposal. Study the ecologycharacteristic of AOB and nitrification and adsorption of sediments in coastal wetland have very important signification for the research of nitrogen circling and rehabilitate in littoral.In this paper,the distribution of Ammonia-Oxidizing Bacteria(AOB) and its'environmental factors in different environment sediments of Yellow river delta were researcched by using three-fluid method.It was found that the number of AOB in different environment sediments is different.The number of AOB in plant rhizomatic sediments is bigger than that in non-rhizomatic and low estuary sediments.The distribution of AOB is interrelated to organic matter in sediment.And is disrelated to the pH and concentrition of NH4+-N in sediments.The zoology characteristic of nitrification bacteria in different environment of wetland was studied by using molecular biological technology.There are both similar nitrification bacteria communities and differential communities in different environment sediment.It has manifested characteristic that the diversity of AOB in non-plant area and low estuary is prolific than that in plant area. And the diversity of AOB is interrelated to pH of sediment.The adsorptive characteristic and impact factors of NH4+-N on sediment were studied by using simulant method in lab.It was found that the adsorptive characteristic of wetland sediments were accordence with both Freundlich and Langmuir isotherm.accord to the Langmuir isotherm,the limit adsorptive capacity was 111.5mg/kg.The adsorptive capacity of sediments was affected by concentration,temperature,pH and salinity.With the NH4+-N concentration rising,the adsorptive capacity of wetland sediment increased,too.The adsorption was inhibited because of salty.The adsorptive capacity decreased if pH of solution was too high or too low.The nitrification of wetland sediments and its'impact factors were studied by using simulant method in lab. The nitrifying activity of soils from different environment was different.The influence of pH on nitrifying activity was strongest.Alkaline condition is more favorable than acidic condiation for nitrification. Low pH significantly inhibited nitrification of bacteria. The optimum temperature for nitrification was 28℃or so and Low temperature inhibited nitrification.Nitrification wasn't sensitive for the salinity increasing at lower salinities.But nitrification was inhibited when salinity was too high.