中国沿海典型赤潮生物氮同位素分馏作用及其动力学研究

Nitrogen is one of the most important nutrients in the ocean. The study of nitrogen isotope fractionation is significant for the understanding of the element biochemical process and some problems on marine environment. This project studied the effect of N sources on N isotope fractionation of marine phytoplankton. Based on the model of d15N uptake kinetic, fractionation e in the individual N sources were obtained. The effects of mixture N-sources and DON (dissolved organic nitrogen) on the fractionation were studied. It was found that the value of e in the mixture N-sources was between the maximum and the minimum of e values in the individual N sources, which explained the field work of Montoya et al. in Chesapeak. The δ15N of DON was similar to the δ15N of PN in the exponential phase and was 3.7‰ more than PN in the stationary phase. In order to know the relationship between the fractionation and eutrophication and HAB (Harmful algal bloom), we monitored the whole bloom process of HAB occurred in Jiaozhou Bay and studied the fractionation during the process. The nutrient characteristic before and after the bloom was gotten. The relationships between fractionation and HAB and eutrophication were studied and explored. As the achievement of the project, two papers were published. Two papers were submitted. 1-2 papers will be finished soon.

氮是海洋中最重要的营养元素，通过氮同位素分馏作用机制的研究将对深入研究海洋中该元素复杂的生物化学过程、揭示有关海洋生态环境问题有重要意义。本项目将研究我国主要赤潮生物氮同位素分馏作用机制，分析该作用与环境富营养化以及有害赤潮形成间的关系，考察δ15N动力学对新生产力和再生生产力测定的影响，建立赤潮生物理学δ15N吸收动力学模型。