摘要
为揭示大气湿沉降对胶州湾营养盐的输送通量及其生态效应,分别于2015年6—8月(夏季)、9—11月(秋季)采集胶州湾降水样品,测定了降水中不同形态N、P、Si的浓度。结果表明,降水中不同形态营养盐的浓度变化较大,且均与降水量呈负相关关系,其中NH4-N和NO3-N的浓度较高,溶解有机氮(DON)占溶解态总氮(DTN)含量的25.9%,而NO_2-N,PO_4-P和SiO_3-Si的浓度均很低。溶解无机氮(DIN)、DON、PO_4-P以及SiO_3-Si的湿沉降通量分别为141.7、61.87、0.35 mmol m^(-2)a^(-1)和0.12 mmol m^(-2)a^(-1)。受降水量和营养物质来源制约,各项营养盐湿沉降通量时间变化显著。农业活动导致的无机氮排放构成了胶州湾湿沉降DIN的主要来源。大气湿沉降DIN、DON、PO_4-P和SiO_3-Si分别占胶州湾总输入负荷的9.04%、10.24%、0.57%和0.17%,湿沉降输入的PO_4-P在夏、秋季分别可以支持0.575 mgC m^2d^(-1)和1.42 mg C m^2d^(-1)的新生产力;雨水中DIN/P比值高达1 617,突发性强降雨带来的营养盐输入会加剧表层水体的P限制和Si限制,对胶州湾浮游植物群落结构和粒级结构产生重要影响。大气湿沉降是胶州湾生源要素生物地球化学过程的重要一环,对营养物质收支的贡献及可能引发的生态效应不容忽视。
Recently, owing to anthropogenic activities such as fossil fuel combustion and agricultural fertilization, the amounts of nutrients and other pollutants entering the marine environment via atmospheric wet deposition have been increasing, Large amounts of nutrients input resulting from short-term heavy rainfall may result in the temporary eutrophication of surface waters, and could even lead to red tides. Therefore, research has presently been focused on atmospheric wet deposition. Jiaozhou Bay, North China, is a typical semi-closed bay negatively affected by natural changes and anthropogenic activities. With the rapid development of the economy, society, and the population growth of Qingdao City, anthropogenic activities have resulted in ecological environmental deterioration, such as frequent occurrence of smog and sandstorms. This has resulted in a considerable increase in the transfer rate of terrigenous pollutants into the sea via atmospheric wet deposition. Thus, research on the nutrients of atmospheric wet deposition in Jiaozhou Bay has received considerable attention from governments, society, and scientists. To evaluate the nutrients influxes by atmospheric wet deposition and their ecological effects on Jiaozhou Bay, 33 wet deposition samples were collected in Jiaozhou Bay from June to November 2015. The concentrations of nutrients （NH4-N, NO3-N, NO2-N, PO4-P, and SiO3-Si） , dissolved total nitrogen （ DTN）, and dissolved organic nitrogen （DON） were determined using a continuous flow analyzer. Results showed significant differences among the monthly average concentrations for nutrients, and negative relationships between several nutrients and the amount of precipitation. The concentrations of NH4-N and NO3-N in the rainwater were high, whereas the concentrations of NO2-N, POa-P and Si03-Si were low. Dissolved inorganic nitrogen （DIN） was the dominant species, accounting for 74.1% of DTN with DON accounting for 25.9% of DTN. The wet deposition fluxes of DIN, DON, POn-P and SiO3-Siwere estima
出处
《生态学报》
CAS
CSCD
北大核心
2017年第14期4817-4830,共14页
Acta Ecologica Sinica
基金
国家重点基础研究973项目课题(2015CB452901)
青岛海洋国家实验室鳌山卓越科学家人才专项(2015ASTP-OS13)
国家自然科学基金委-山东省联合基金(U1406403)
关键词
营养盐
大气湿沉降通量
生态效应
胶州湾
夏季
秋季
nutrients
fluxes of atmospheric wet deposition
ecological effects
Jiaozhou Bay
summer
autumn
