赣江流域水体无机氮分布特征

The Distributive Character of Inorganic Nitrogen in the Ganjiang River Catchments

于2006年1月和7月对赣江流域地表水进行了系统采集,分析研究了水体中各形态无机氮分布特征,结果表明,赣江水体中主要的氮素形式是NO3--N,枯水期赣江流域NO3--N、DIN从上游至下游呈明显的上升趋势,NH4+-N变化不明显。丰水期从上游至下游NO3--N含量逐渐降低,但降幅不大,而NH4+-N和DIN在中游含量最低,下游最高。主要支流中枯水期以袁水NO3--N和DIN含量最高,赣江中支NH4+-N含量为全流域最大值,而丰水期以禾水NO3--N为流域最高值。赣江主干流丰水期各形态无机氮含量明显低于枯水期。氮污染较重的袁水的输入致使G38(樟树)处氮含量明显高于其它地方。

Various forms of inorganic nitrogen （N） of surface water were investigated in the Ganjiang River catchments during January （ dry season） and July （ flood season）, 2006. The results indicated that nitrate N （ NO^3- - N） was the main existence form of inorganic N among the Ganjiang River catchments. The concentrations of NO^3- - N and DIN showed increasing trend from upstream to downstream in the Ganjiang River catchments during dry season, but NH4^＋ - N showed no significant variation trend. The concentrations of NO^3- - N showed slight decreasing trend from upstream to downstream in the Ganjiang River catchments during flood season, but the concentrations of NH4^＋- N and DIN were the lowest in the middle stream and the highest in the downstream. The concentrations of NO^3- - N and DIN in the Yuanshui River were the highest than the other major tributaries during dry season, and the concentrations of NH4^＋ - N were the highest in the Ganjiang middle tributaries. But the NO^3- - N concentrations were the highest in the Heshui River. The concentrations of various forms of inorganic N were apparently lower in the flood season than in the dry season. The N concentrations were apparently higher at the G38 than other sites due to the recharge from the Yuanshui River that was polluted by nitrogen seriously.