大型海藻龙须菜与锥状斯氏藻间的营养竞争研究  

COMPETITION ON NUTRIENTS BETWEEN GACILARIA LEMANEIFORMIS AND SCRIPPSIELLA TROCHOIDEA(STEIN) LOEBLICH Ⅲ

作　　者：张善东[1] 宋秀贤[1] 王悠[1] 俞志明[1] 

机构地区：[1]中国科学院海洋研究所海洋生态与环境科学重点实验室

出　　处：《海洋与湖沼》2005年第6期556-561,共6页Oceanologia Et Limnologia Sinica

基　　金：国家杰出青年基金项目;40025614号;中国科学院创新工程项目;KZCX3-SW-214号;国家重点基础研究(赤潮"973")项目;2001CB409710号。

摘　　要：利用生物和化学方法研究了大型海藻龙须菜(Gracilaria lemaneiformis)与赤潮生物锥状斯氏藻(Scrippsiella trochoidea(Stein)LoeblichⅢ)共培养时二者的生长情况,以及二者之间营养盐NO3-、PO43-竞争的情况。结果显示,两者共培养时,由于龙须菜的影响,锥状斯氏藻的生长周期以及所能达到的最大细胞密度与对照组相比都有所下降,且受抑制程度随龙须菜起始密度的增大而增强;而锥状斯氏藻对于龙须菜的生长不构成明显的影响。当龙须菜起始密度较低时(0.2、0.1gFW/L),共培养组微藻细胞密度的下降是因为水体中NO3-的耗尽;当龙须菜起始密度较高时(0.5gFW/L),共培养组微藻细胞密度的下降可能是因为龙须菜与微藻之间的“互荫效应”,或者龙须菜能够分泌出足够浓度的克生物质所致。龙须菜可作为有效吸收营养盐的大型海藻,用以降低近海水域富营养化程度及有害赤潮发生的几率。In recent years, harmful algal blooms （HABs） occurred in more localities and more frequently than before, which have caused serious problems in coastal marine ecological environment and massive mortality of cultured organisms in China. Various mitigating methods, physical or chemical ones, have been applied, but the re- sults were unsatisfactory with probable negative impact on marine ecosystem. Biological strategy was therefore suggested recently for its potential HABs mitigating ability with fewer side effects. Using macroalgae to remove microalgae is an alternative measure advocated by many scientists for its combined merit. Macroalga is popular in aquatic ecosystem. They absorb nutrients quickly from water to build their bodies. Some of them could also release certain allelopathic materials to kill microalgae cells. When harvested, they can carry lots of nutrients from the water column onto the land. To study the feasibility of applying macroalgae in HABs mitigating, macroalga Gracilaria lemaneiformis, a common species in China coasts, was selected to study its interference with and competition for nu- trients against a bloom-causing dinoflagellate Scrippsiella trochoidea （Stein） Loeblich Ⅲ, which was originally separated from Jiaozhou Bay of China, under controlled laboratory conditions. The initial density of G. lemaneiformis was designed at three gradients of 0.5, 0.2, and 0. 1 gFW/L. The S. trochoidea in exponential phase were inoculated into a new culture medium to reach an initial cell density of ca. 3 × 10^3 cells/ml. Results showed that G. lemameiformis had obvious algicidal effects on S. trochoidea in the coexisting system. When co-cultured, both growth period and maximum cell density of S. trochoidea were decreased, and the degree of the decrease was positively related to the initial density of G. lemameiformis. Oppositely, S. trochoidea had little effects on growth of G. lemoneiformis and their daily increasing rates presented no significant difference with that in mono cultivating syste

关 键 词：龙须菜 锥状斯氏藻 共培养 营养竞争 

分 类 号：X55[环境科学与工程—环境工程]