氮磷营养因子对赤潮异弯藻生长的影响

研究了N、P营养浓度对赤潮异弯藻(Heterosigma akashiwo)生长的影响.结果表明,该藻的生长速率与N、P营养因子浓度的关系符合Monod公式.在NO₃^--N浓度达到7.5 mg·L^-1时,赤潮异弯藻开始生长;浓度为3.75～75 mg·L^-1时,赤潮异弯藻的比生长速率与NO₃^--N浓度成正比关系.N营养充足时,赤潮异弯藻的最大生长速率μ_m-n=0.3475·d^-1，K_s-n=18.91 mg·L^-1.PO₄^--P浓度为0～1.0 mg·L^-1时,赤潮异弯藻的比生长速率与P浓度成正比关系；P营养充足时,赤潮异弯藻的最大生长速率μ_m-p=0.3024·d^-1，K_s-p=0.4086 mg·L^-1.N/P达到25后藻细胞浓度达到最大，表明N/P为25时最适合赤潮异弯藻生长.赤潮异弯藻最适合在N 37.5～225.0 mg·L^-1、P 5.0～50.0 mg·L^-1、N/P=25条件下生长.

Effects of nutrients nitrogen and phosphorus on Heterosigma akashiwo growth

The study showed that the relationships between the specific growth rate (up) of Heterosigma akashiwo and the concentrations of nutrients nitrogen and phosphorus in water body accorded with Monod equation. H. akashiwo started to grow when the concentration of NO3(-)-N was higher than 7.5 mg x L(-1), and the specific growth rate (micro) of the algae was proportional to the concentration of NO3(-)-N between 3.75 to approximately 75 mg x L(-1). The maximum growth rate of H. akashiwo (micro/m-n) was 0.3475 x d(-1), and the half saturated constant (Ks-n) was 18.91 mg x L(-1). The specific growth rate of the alga was proportional to the concentration of PO4-P between 0 to approximately 1.0 mg x L(-1).The maximum growth rate of H. akashiwo ( microm-p) was 0.3024 x d(-1), and Ks-n was 0.4086 mg x L(-1). The most suitable growth conditions for H. akashiwo were 37.5 to approximately 225.0 mg x L(-1) NO3(-)-N, 5.0 to approximately 50.0 mg x L(-1) PO4-P, and N/P 25.