丹江口水库氮干沉降的时空特征及生态影响  

Spatial and temporal characteristics and ecological impacts of nitrogen dry deposition in the Danjiangkou Reservoir

作　　者：武俐[1] 宋百惠 李啸林 王海坡 赵同谦[1] 王祖恒 WU Li;SONG Bai-hui;LI Xiao-lin;WANG Hai-po;ZHAO Tong-qian;WANG Zu-heng(Institute of Resources and Environment,Henan Polytechnic University,Jiaozuo 454000,Henan,China;Sanmenxia Aoke Chemical Co.,Ltd,Sanmenxia 472000,Henan,China)

机构地区：[1]河南理工大学资源环境学院,河南焦作454000 [2]三门峡奥科化工有限公司,河南三门峡472000

出　　处：《生态学杂志》2023年第1期190-197,共8页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(U1704241和41702174);中原科技创新领军人才项目(194200510010)资助。

摘　　要：氮沉降是水库水体外源氮输入的重要途径,对水生态系统有直接影响。通过采集丹江口水库淅川库区162个大气氮干沉降样品,分析了库区氮干沉降通量特征、典型农业期对氮沉降的贡献以及潜在的生态影响。结果表明:库区氮干沉降通量为22.60 kg N·hm^(-2)·a^(-1),有机氮沉降量占总氮沉降通量的50.8%,以有机氮沉降为主;库区东北与西南区域氮干沉降通量较高,而北部和东南区域较低;春、秋季库区总氮、有机氮和尿素沉降通量高于夏、冬季,铵态氮沉降通量在夏季最高,硝态氮沉降通量在冬季最高,与氮素的来源、农业生产活动以及气象因素有关;典型农业期氮干沉降量月均值是非典型农业期的1.75倍,农业活动对总沉降量的贡献不容忽视;淅川库区大气氮干沉降通量是我国湖泊营养盐总氮沉降临界负荷的2.26倍,有潜在的水体富营养化风险,需重点关注典型农业活动期对水生态系统的影响。Nitrogen deposition is a vital pathway for the input of exogenous nitrogen into reservoir waters, which has a direct effect on aquatic ecosystems. By collecting 162 atmospheric nitrogen dry deposition samples from the Xichuan area of the Danjiangkou Reservoir, we analyzed the characteristics of nitrogen dry deposition fluxes, the contribution of typical agricultural periods to nitrogen deposition, and potential ecological impacts. The results showed that the nitrogen dry deposition flux was 22.60 kg N·hm^(-2)·a^(-1)and that organic nitrogen deposition accounted for approximately 50.8% of the total nitrogen deposition fluxes. The dry deposition was dominated by organic nitrogen deposition. The nitrogen dry deposition fluxes were higher in the northeast and southwest regions than that in the north and southwest regions of the reservoir. Fluxes of total nitrogen, organic nitrogen, and urea deposition were higher in spring and autumn than in summer and winter. Seasonal characteristics were related to nitrogen source, agricultural production activities, and meteorological factors. The mean value of monthly nitrogen dry deposition during the typical agricultural period was 1.75 times higher than that during the atypical agricultural period. The contribution of agricultural activities to the total deposition could not be ignored. Atmospheric nitrogen dry deposition flux was 2.26 times that of the critical load of total nitrogen deposition from nutrients in lakes in China and was associated with the potential risk of water eutrophication. Given that agricultural activities significantly affect nitrogen deposition, attention should be paid to the effects of typical agricultural activity periods on aquatic ecosystems.

关 键 词：丹江口水库 氮沉降 时空特征 农业活动 生态影响 

分 类 号：X524[环境科学与工程—环境工程]