Effects of colloids on the nitrogen fixation rates in surface water in beibu gulf of China

The influences of colloids on nitrogen fixation rate of surface water were studied in the Beibu Gulf of China. The results show that the increment ratios of nitrogen fixation rates in water samples that cultured with colloids added are -96% to 1456% in spring, -9% to 64% in summer, -72% to 122% in autumn and -13% to 216% in winter. The enhancement is most significant in spring. Generally speaking, colloids can promote the nitrogen fixation rates in surface water to some extent.