Pilot Studies On The Mocroecology Of Suzjou Creek

Microorganisms play significant role in the energy flow and nutriments recycle in aquatic ecosystem. To study the distribution of physiological groups of bacteria and analyze the correlation between which with the main environment factors can accurately understand the status and role of bacteria in the aquatic ecosystem of Suzhou Creek. The population distribution of physiological groups of bacteria,including ammonifying bacteria, denitrifying bacteria, nitrobacteria and nitroso bacteria, organic phosphate dissolving bacteria and inorganic phosphate dissolving bacteria in water body and sediment of Suzhou Creek are studied with MPN and flat account method from Jan. 2002 to Mar. 2003. The role of these physiological groups of bacteria in Suzhou Creek aquatic ecosystem is discussed. The factors which affect the growth and function of ammonifying bacteria in Suzhou Creek are studied with altering the environmental conditions.The amounts of microorganisms in Zhejiang road-bridge and Wuning road-bridge sections are maximal. Because the two sections are located in midtown, is badly contaminated with domestic fecal sewage and industrial sewage. The plentiful organic matters provide abundant nutriments and energy sources for microorganisms. The population distribution of bacteria which participate in N & P cycle correlates with the content of correlated nutrient salt in water body. The sediment release experiment tested out that microorganisms in water body can be supplied from sediment. Ammonifiers in Suzhou Creek can not use inorganic nitrogen and carbamide as nitrogen source; additional carbon source and garbage lixivium have little influence on ammonifiers growth; high content of salt and low temperature restrain ammonifiers growth; alkalescent condition has little influence on ammonifiers, but acidic condition restrain ammonifiers growth; the biomass of ammonifiers are not necessary correlated with the function of ammonifiers, adding glucose with 1g/l content into the water sample obviously promote the growth and function of ammonifiers.Physiological groups of bacteria play significant role in the translation andtransference of nitrogen and phosphor in Suzhou Creek. They are important indicators of water quality. Through physiological groups of bacteria, we can inquire into treatment mechanisms of water treatment system. The present content of ammonia in Suzhou Creek water body is high. The environmental conditions are propitious to ammonifiers growth in Suzhou Creek. Through primary analysis on the characteristics of ammonifiers growth and function, ammonification is a possibly important origin of ammonia in Suzhou Creek water body. The studies tested that adding K2HPO4 can reduce ammonifiers function. It maybe has important reference value for ecosystem resume in Suzhou Creek.A mass of ammonifiers in water body and sediment can make ammonia accumulate in water body through ammonification .The study in succession must give emphasis to bring more ammonia into nitration. That will expedite the nitrogen cycle and remove nitrogen in water body.