2011年烟台四十里湾微微型金藻褐潮分析

ANALYSIS ON BROWN TIDE OF AUREOCOCCUS ANOPHAGEFFERENS AT YANTAI SISHILI BAY,YEAR 2011

依据烟台四十里湾赤潮常规监测资料及烟台金沙滩旅游度假区气象观测资料,分析了2011年四十里湾褐潮特点及环境背景。褐潮原因种为微微型金藻Aureococcus anophagefferens;褐潮特点为:海水棕褐色,透明度低,发生于春夏季节,持续时间长,分布范围广,导致扇贝滞长或死亡。5月下旬,水温16℃左右,海水中N严重富营养化,为褐潮藻生长提供了适宜的水文条件及营养物质基础;浮游植物物种多样性指数仅为0.47,群落稳定性差,为褐潮藻大量繁殖提供了契机;又恰逢连续多日阴雨、低光照天气从而引发褐潮暴发。异养及自养的混合营养方式使褐潮藻在低透明度环境中占据生态优势,持续生长3个月。高含量的P非褐潮暴发的必要条件。褐潮藻的兼养模式使海水pH、DO不似自养藻类赤潮因光合作用而大幅度上升。大量繁殖的海洋细菌积聚微藻细胞、有机及无机碎屑等黏附于扇贝网笼及扇贝体,妨碍扇贝呼吸及摄食,导致扇贝生长缓慢甚至死亡。

It is to ana tide monitoring data lyze the Brown Tide happened at Sishili bay at Yantai Sishili Bay from year of 2009-2011 from May to Aug. 2011, based on red and meteorological observation data at Yantai Gold beach tourism area. The brown tide organisms were Aureococcus anophagefferens. This brown tide shows： tan sea with lower transparency, happened on spring and summer with long time continuing, cultivated Scallops stopped growing, on late of May the water temperature is up to around 16~C, the contents of nitrogen in the sea is up suddenly. That Provide suitable hydrological conditions and trophic basis for brown tide algae growing. It gives A. anophagefferens the chance to proliferate that the diversity index of phytoplankton is only 0.47 and the phytoplankton community structure is under unstable status. In the meanwhile the continuous cloud and raining weather with lower sunny caused brown tide. A. anophagefferens＇s mixotrophic mode of Heterotrophic and Autotrophic makes it more competitive on time, and have a longer continuance under prosperous growth. Heterotrophic mode as the main living way is different than Autotrophic mode, can not make sea pH and DO a serious rise due to photosynthesis. Heterotrophic bacteria replicating extensively gathers Algae cells, organic ＆. inorganic scraps, etc, which attach to the skirt and gill of scallops for a long time, hinder scallops breath and feeding, and cause Scallops grow slowly and even die.