基于海洋生态在线监测浮标数据的钦州湾藻华过程研究

Analysis of Algal Bloom in Qinzhou Bay Based on Marine Ecology Online Monitoring Buoy Data

关键词:  藻华  广西  在线监测  浮标  预警

Key words:  algal bloom  Guangxi  online monitoring  buoy  early warning

摘要:

2018年8月19日至23日，广西钦州湾海域发生由红色赤潮藻（Akashiwo sanguinea）引起的藻华暴发现象。为探讨在线监测浮标应用于赤潮预警研究的作用，本文使用2018年8月16日至27日位于藻华海域的GX11号广西海洋生态在线监测浮标数据，分析藻华暴发过程前后风速、气温、水温、盐度、pH值、溶解氧、叶绿素a等环境要素的变化趋势，讨论环境因子对藻类增殖的影响规律。结果表明：气温、水温回升以及风速由大减小，有利于藻类聚集增殖，是藻华发生的环境诱因；在藻华暴发中期的4 d中pH值最高值分别为8.20，8.49，8.42，8.24，溶解氧最高值分别为9.01，12.26，11.81，10.22 mg/L，叶绿素a最高值分别为42.2，52.3，25.4，15.6 μg/L，均主要出现在中午至下午时段，且数值明显比藻华过程前期和消退期高；pH值、溶解氧、叶绿素a呈显著正相关，并具有联动的昼夜变化规律。结合气象条件因素，当在线监测显示pH值、溶解氧、叶绿素a出现同步的波动增大，特别是叶绿素a达到或接近10.0 μg/L时，可开展部分赤潮生物种类的藻华预警。

Abstract:

From August 20 to 23,2018,algal blooms caused by the Akashiwo sanguinea occurred in Qinzhou Bay,Guangxi.In order to explore the role of online monitoring buoys in red tide early warning research,based on the data of Guangxi marine ecological online monitoring buoy GX11 located in the algal bloom sea area from August 16 to 27,2018,the variation trends of environmental factors such as wind speed,air temperature,water temperature,salinity,pH value,dissolved oxygen and chlorophyll before and after the algal bloom were analyzed,and the influence of environmental factors on algae proliferation was discussed.The results showed that the rise of air temperature and water temperature and the great decrease of wind speed were beneficial to the aggregation and proliferation of algae,which were the environmental inducements of algae bloom.During the four days of algal bloom outbreak stage,the highest pH values were 8.20,8.49,8.42 and 8.24,respectively,the highest values of dissolved oxygen were 9.01,12.26,11.81,10.22 mg/L,and the highest values of chlorophyll a were 42.2,52.3,25.4,15.6 μg/L,respectively,all of which mainly appeared from noon to afternoon and the values were significantly higher than those in the early and regression phases of the algal bloom process.There was a significant positive correlation between pH value,dissolved oxygen and chlorophyll a,and there was a linked diurnal change rule.Combined with meteorological conditions,the early warning of algal blooms for some species of red tide organisms can be carried out when online monitoring shows that the synchronous fluctuation of pH value,dissolved oxygen and chlorophyll a increases,especially when chlorophyll a reaches or approaches 10.0 μg/L.