养殖水体沉积物中氮的形态、分布及环境效应

Nitrogenous Forms, Distribution and Environmental Impacts in the Sediment of Aquacultural Water Columm

养殖水体沉积物中的氮可分为有机态氮和无机态氮,以有机态氮为主(70％～90％)。无机态氮主要有NO3--N、NO2--N和NH4+-N,其中以NH4+-N为主。各形态的氮含量在水平方向上的分布随距污染源的远近而有小到大变化;垂直方向上的分布则是:NH4+-N随沉积深度的增加含量增大,NO3--N随沉积深度的增加含量减小,而NO2--N随沉积深度的变化不明显。

In aquacultural waters, there were two nitrogenous forms: organic nitrogen, which comprised 70% -90% in the sediments, and inorganic nitrogen, which primarily included NO3-N,NO2-- N and NH4+ -N, among which NO4+ - N accounted for high proportion. All nitrogenous forms increased with their distance to contaminated areas, and decreased with their distance far from the contaminated areas. The content of NH4+- N increased with an increase in depth of sediment.On the other hand, the NO3- - N level decreased with increase in sediment depth with invariable NO2- ~ N level.