由养殖废水导致的湛江硇洲岛海域夜光藻赤潮

Harmful Algal Blooms of Noctiluca scintillans Resulted from Wastewater of Aquaculture in the Waters Around the Naozhou Island, Zhanjiang, China

于2002年2月对湛江硇洲海域发生的夜光藻赤潮进行了调查,结果发现:该赤潮发生的海域水温19℃,盐度27～32,pH值6.87～8.33,溶解氧2.81～8.11mg·L-1,化学需氧量0.97～492.28mg·L-1,氨氮0.002～0.258mg·L-1,硝酸盐0.040～0.262mg·L-1,亚硝酸盐0.005～0.175mg·L-1,无机氮0.047～0.529mg·L-1,活性磷酸盐0.048～1.682mg·L-1。这是由于当地对虾养殖池清塘,将大量富营养化养殖废水直接排入海,从而造成该海域发生长约2km,宽约50m,面积约10hm2的红色夜光藻赤潮的主要原因。

An investigation of harmful algal blooms of Noctiluca scintillans was conducted in the waters around the Naozhou Island, Zhanjiang, China. The investigation showed that the harmful algal blooms appeared in the waters around the Island when the sea temperature was 19 ℃, the salinity 27 - 32, the pH 6.87 - 8.33, the dissolved oxygen 2. 81 -8. 11 mg · L-1 , the chemical oxygen demand 0. 97 -492. 28 mg · L-1 , the ammonia nitrogen 0. 002 -0. 258 mg · L-1 , the nitrate 0. 04 -0. 262 mg · L-1 , the nitrite 0. 005 -0. 175 mg · L-1 , the inorganic nitrogen 0. 047 -0. 529 mg · L-1, and the reactive phosphate 0. 048 - 1. 682 mg · L-. This was due to the fact that large amounts of eutrophic waste water were discharged into the sea waters directly from the local prawn ponds due to pond cleaning. This mass of eutrophic waste water was the major factor that caused the harm- ful algal blooms of N. scintillans covering the waters 2 km long and 50 m wide, or a sea area of 10 hectares in the waters around the Island.