氮磷比对蛋白核小球藻和塔玛亚历山大藻种间竞争的影响

Effect of nitrogen-phosphorus ratio on the interspecific competition of Chlorella pyrenoidosa and Alexandrium tamarense

通过单独培养和共同培养的方法,以NaNO3和KH2PO3为氮源和磷源,研究了氮磷比（4、6、9、10、13、16、22、36和91）对蛋白核小球藻（Chlorella pyrenoidosa）和塔玛亚历山大藻（Alexandrium tamarense）生长和种间竞争的影响,并对其作用机制进行了探讨.结果表明：在单独培养模式下,蛋白核小球藻在N/P为4-22时生长适宜,N/P＞22时生长受抑制,而塔玛亚历山大藻在N/P为4和6时生长适宜,N/P＞6时生长受抑制;在共同培养模式下,蛋白核小球藻具有竞争优势,而塔玛亚历山大藻的生长受抑制,且N/P为13和16时蛋白核小球藻种群竞争优势最明显;蛋白核小球藻和塔玛亚历山大藻的培养滤液对彼此生长均未产生抑制作用,由此推测,两种微藻的种间竞争主要以资源利用性竞争为主.结果可为开发利用饵料藻进行赤潮生物防控提供一些理论依据.

The effect of nitrogen-phosphorus ratio （ N/P ） on the interspecific competition of ChloreUa pyrenoidosa and Alexandrium tamarense was investigated under two modes of monoculture and co-cuhure by choosing NaNO3 and KH2 PO3 as N and P source. The results showed that under monoculture mode, C. pyrenoidosa grew normally with N/P ranging from 4 to 22 and was inhibited when the ratio was above 22. In comparison, A. tarnarense grew favorably at N/P of 4 and 6, and its growth was inhibited when N/P exceeded 6. Under co-culture condition, C. pyrertoidosa obtained competitive advantage,especially when N/P is 13 and 16. There was no reciprocal inhibiting effect of the culture filtrate between C. pyrenoidosa and A. tamarense. This indicated that their interspecific competition was mainly on resource utilization. This study provides basic data for the control of red tide using prey microalgae.