洱海水-陆界面溶解性有机氮组成结构及生物有效性-以永安江为例

发布时间：2018-04-13 23:21

  本文选题：洱海水-陆界面 + 溶解性有机氮　； 参考：《光谱学与光谱分析》2017年04期

【摘要】：利用紫外与三维荧光光谱技术,研究了洱海水-陆界面溶解性有机氮(DON)组成结构及生物有效性特征,并探讨了其对湖泊水质影响。结果表明:(1)水-陆界面经由永安江输入洱海DON浓度在0.25~1.39mg·L~(-1)之间,从河流到湖内以夏秋两季DON浓度较高;经由永安江输入洱海DON负荷量在0.48~2.34t之间,其中以夏季DON负荷量最高,表明经由入湖河流输入洱海的DON对洱海水质影响潜在风险较大,尤其夏季明显。(2)水-陆界面经由永安江输入洱海的DON组成主要以类腐殖质物质为主,永安江沿程到湖内衰解特征明显且生物有效性为15.27%,而类蛋白和可溶性微生物代谢产物则出现不同程度累积,累积率分别为42.00%和20.68%;DON组分的分子腐殖化程度经由永安江到洱海湖内呈渐降趋势且降低了14.97%。同时,分子芳香环取代基从以脂肪链为主逐渐向以羰基、羧基、羟基、酯类为主转变,尤其在夏季表现明显。(3)水-陆界面经由永安江输入洱海DON组成特征参数(P_((Ⅲ+Ⅴ,n))/P_((Ⅰ+Ⅱ,n))和A_(253)/A_(203)值)与其不同形态氮含量显著相关(R~2=0.64~0.74,P0.1,P0.05),即永安江输入洱海DON结构影响其生物有效性;水-陆界面DON不同结构特征参数与水质呈显著正相关(R=0.82~0.96,p0.05,p0.01),表明水-陆界面经由永安江入湖DON组成结构及生物有效性对洱海水污染有一定贡献,尤其在夏季受陆源等人类活动影响较大时,影响更为突出;由此可见,洱海水-陆界面经由永安江入湖DON组成结构变化(如P_((Ⅲ+Ⅴ,n))/P_((Ⅰ+Ⅱ,n)),A_(253)/A_(203))可在一定程度上反映洱海水质状况。
[Abstract]:The composition and bioavailability of dissolved organic nitrogen (DON) at the water-land interface of Erhai Lake were studied by means of UV and 3D fluorescence spectroscopy, and the effects of DON on lake water quality were also discussed.The results show that the DON concentration of Erhai Lake is higher in summer and autumn from river to lake at the water-land interface, and the DON load of Erhai Lake input through Yongan River is between 0.48 and 2.34 t, in which the DON load in summer is the highest.The results show that the potential risk of DON input into Erhai Lake from lake river is great, especially in summer.) the composition of DON input from the water-land interface to Erhai Lake via Yongan River is mainly humus-like material.The characteristics of senescence and bioavailability from Yongan River to the lake were 15.27, while protein like and soluble microbial metabolites accumulated in varying degrees.The accumulation rates of 42.00% and 20.68% of don components showed a decreasing trend and a decrease of 14.97% through the Yongan River to Erhai Lake.At the same time, the molecular aromatic ring substituents gradually changed from fatty chain to carbonyl, carboxyl, hydroxyl and ester.Especially in summer, the water-land interface input the characteristic parameter of DON composition of Erhai Lake via the Yongan River (鈪，

本文编号：1746675