In recent years, the eutrophication of seawater has led proliferation of large seaweeds in offshore waters, becoming a worldwide environmental problem. Since 2007, the green tide of Ulva prolifera has continuously broken out in the Yellow Sea, causing huge economic losses. In order to investigate the relation between macroalgae and the ratio of nitrogen to phosphorus (N/P), and the competition mechanism with other macroalgae, we studied the growth of U. prolifera and U. lactuca when pure culture and co-culture. The results showed that: (1) When U. prolifera was pure cultured, the higher or lower N/P can promote the growth of U. prolifera. (2) When U. lactuca was pure cultured, the effect of the N/P on U. lactuca is not obvious. (3) U. prolifera growth was inhibited to some extent under the different N/P conditions when U. prolifera and U. lactuca were co-cultured, and the lowest N/P group was affected the most. (4) The N/P in the Subei Shoal is more suitable for the growth of U. prolifera, which may be one of the main reasons for the large-scale outbreak of U. prolifera green tide.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |