Concentrations distributions of dissolved inorganic nitrogen(DIN) and NO~-_3-N in overlying water varied seasonally,which got their maximum concentration in October 2004 while the NH~+_4-N concentration showed a little difference.

• 上覆水中溶解无机氮(DIN)和NO3--N含量的季节变化趋势一致,在2004-10达到峰值,NH4+-N的季节变化稍有不同;