摘要
湖泊蓝藻水华期间,水体无机氮缺乏,有机氮的循环转化能为浮游植物提供重要的氮素补充,而藻华频发的中国东部湖泊有机氮浓度的时空特征和影响因素尚不明确。该文基于区域划分系统分析了中国东部84个湖泊有机氮浓度特征和影响因素,并对比分析了区域典型湖泊鄱阳湖、太湖有机氮浓度的长期变化。结果表明,调查湖泊枯水期有机氮浓度为0.08~3.30 mg/L,均值为(0.85±0.46)mg/L,占总氮比例为8.01%~99.45%,均值为(64.67±22.72)%;丰水期有机氮浓度为0.05~1.47 mg/L,均值为(0.68±0.42)mg/L,占总氮比例为9.15%~93.39%,均值为(59.12±20.77)%。有机氮浓度均值呈现枯水期"西高东低"而丰水期"西低东高"的特征,即枯水期长江(宜昌-望江段)流域湖泊>长江(望江-入海口段)流域湖泊>淮河流域湖泊,而丰水期与之相反。从有机氮占总氮比例的季节特征来看,长江(宜昌-望江段)流域和淮河流域湖泊多数呈现枯水期高于丰水期,而长江(望江-入海口段)流域湖泊多数呈现枯水期低于丰水期。湖泊藻生物量、悬浮物浓度对湖泊有机氮浓度的影响呈现季节和区域性差异,区域典型湖泊鄱阳湖有机氮浓度主要受悬浮物浓度影响,而太湖有机氮浓度主要受藻生物量影响,受悬浮物浓度影响较小。
During cyanobacterial blooms in lakes,inorganic nitrogen concentrations are low,and the transformation of organic nitrogen can supply significant nitrogen nutrition for phytoplankton.However,the spatial and seasonal characteristics and influencing factors of organic nitrogen concentrations in the lakes of eastern China,where cyanobacterial blooms are frequent,are not clear.The seasonal characteristics and influencing factors of organic nitrogen concentration in 84 lakes of eastern China were analyzed based on regional division,and the long-term changes of organic nitrogen concentrations in 2 typical lakes were analyzed as well.Results showed that the concentration of organic nitrogen in lakes of eastern China during the dry period ranged from 0.08 to 3.30 mg/L with a mean of(0.85±0.46)mg/L,and the proportion of total nitrogen ranged from8.01%to 99.45%,with a mean of(64.67±22.72)%.The concentration of organic nitrogen during the flood period ranged from0.05 to 1.47 mg/L with a mean of(0.68±0.42)mg/L,and the proportion of total nitrogen ranged from 9.15%to 93.39%,with a mean of(59.12±20.77)%.The regional mean values of organic nitrogen concentrations showed characteristics of"high in the west and low in the east"during the dry period and"low in the west and high in the east"during the flood period,namely,during the dry period,lakes in the Yangtze River basin(Yichang-Wangjiang section)>lakes in the Yangtze River basin(Wangjiang-estuary section)>lakes in the Huaihe River basin,while the opposite pattern was observed during the flood period.In terms of the seasonal characteristics of organic nitrogen to total nitrogen ratio,most of the lakes in the Yangtze River(Yichang-Wangjiang section)basin and Huaihe River basin showed higher ratios during the dry period than during the flood period,while most of the lakes in the Yangtze River(Wangjiang-estuary section)basin showed lower ratios during the dry period than during the flood period.The influence of algal biomass and suspended matter concentrations on the organic nitrogen concentrations showed seasonal and regional differences.The organic nitrogen concentration in Lake Poyang is mainly influenced by suspended solid concentrations,while the organic nitrogen concentration in Lake Taihu is mainly influenced by algal biomass and less influenced by suspended solid concentrations.
作者
丁润楠
姚晓龙
傅大放
张路
DING Runnan;YAO Xiaolong;FU Dafang;ZHANG Lu(School of Civil Engineering,Southeast University,Nanjing 210096,China;Nanjing Institute of Geography&Limnology,Chinese Academy of Sciences,Nanjing 210008,China)
出处
《环境科学与技术》
CAS
CSCD
北大核心
2021年第6期35-42,共8页
Environmental Science & Technology
基金
国家自然科学基金面上基金项目(41771519)
中国科学院南京地理与湖泊研究所引进人才启动项目(NIGLAS2019QD008)。
关键词
东部湖泊
有机氮
时空特征
叶绿素
悬浮物
lakes of eastern China
organic nitrogen
spatial and seasonal characteristics
algal biomass
suspended matter
