Distribution and Activity of Marine Bacterioplankton at Frequent HAB Area of East China Sea
- 生命科学－已发表论文 
[中文文摘]于2006年4~5月对东海近海28°~30.7°N之间的赤潮高发区浮游细菌的分布、活性和群落结构特征进行了调查.采用荧光显微计数法测定细菌丰度,荧光模拟底物法测定细菌胞外酶活性,PCR-DGGE分析该区域的细菌群落结构特征.结果表明,东海赤潮高发区的浮游细菌丰度在5.85×104~9.26×105cells.mL-1之间,其中舟山外海区域较高,在整个调查区域北部海域高于南部海域.β-葡萄糖苷酶的平均活性为0.023μmol.(L.h)-1,氨肽酶的平均活性约为其3.6倍,在5μm以上颗粒中的胞外酶活性平均占总活性分别为47.4%和44.24%.细菌胞外酶活性的分布与细菌丰度的分布无相关性,在整个调查区域南部海域高于北部海域.细菌群落结构和多样性差异较大,南部海域的细菌多样性低于北部海域.人类活动和陆源输入是影响浮游细菌分布的决定性因素,台湾暖流对细菌胞外酶活性及其分布有着决定性的影响,复杂的环境条件是细菌群落结构和多样性差异的主要原因之一.海洋细菌在东海赤潮高发区的生态作用有待进一步研究. [英文文摘]The distribution, activity and community structure of bacterioplankton in surface waterwere investigated at frequent harm fulalgae blooms (HABs) a rea in East China Sea (28b23017bN ) from April to May, 2006. The abundance of bacte riop lankton was determ ined by using the DAPI (4, 62d iamidino222phenylindole) direct count (DDC) method. The B2glucosidase and am inopeptidase activityweremeasured with fluorogenicmodel substra tes. And the bacterial community structure was analyzed by PCR2DGGE. Results showed that bacterial abundance in northern of the sampling area wasmuch more than that in southern of the sampling area. It ranged from 5185@104 ce lls# mL- 1 to 9126@105 ce lls# mL- 1. And there was the highest vaue area outer the costa l of Zhou Shan Island.The average aminopeptidase activity was 316 times of B2glucosidase activity which was 01023 Lmol# ( L# h) - 1 in th is area. The B2 glucosidase ac tivity in > 5Lm fraction contr ibuted 4714% of the tota,l and that of the aminopep tidase activity was 441 24% of the tota .l Bacteria l extracellular enzyme activity had a higher average value in southern of the sampling area. This indica ted that the bacterial activity had no direct relationship with bacteria l abundance. Bac terial diversity and community structure differed from each sampling station. Thereweremore divers in northern sampling area. The results suggested that the human being activity and continental inputting organic matte rsplayed a key role on the distribution of bacterial abundance. The d istribution of bacterial extrace llular enzyme activity wasmainly a ffected by the Taiwan warm current. And it was the complicated unknown factors that caused the difference of the bacterial community structure and diversity from each sampling station. Obviously, it needed furtherwork to enhance the knowledge of the ecological function of the bacte riop lankton at frequentHABs area of the coastal water in East Ch ina Sea.