植物生态学报 ›› 2008, Vol. 32 ›› Issue (6): 1386-1396.DOI: 10.3773/j.issn.1005-264x.2008.06.020

• 研究论文 • 上一篇    下一篇

热冲击和加氯后亚热带海区浮游植物细胞数量的动态变化

江志兵, 曾江宁, 陈全震(), 廖一波, 寿鹿, 徐晓群, 刘晶晶, 黄逸君   

  1. 国家海洋局海洋生态系统与生物地球化学重点实验室, 国家海洋局第二海洋研究所,杭州 310012
  • 收稿日期:2008-04-10 接受日期:2008-06-30 出版日期:2008-04-10 发布日期:2008-11-30
  • 通讯作者: 陈全震
  • 作者简介:*(chenqz6509@126.com)
  • 基金资助:
    国家科技部社会公益研究专项资金(2004DIB3J087);国家海洋局青年科学基金(2005106);浙江省自然科学基金(Y504012)

DYNAMIC CHANGE OF PHYTOPLANKTON CELL DENSITY AFTER THERMAL SHOCK AND CHLORINATION IN A SUBTROPICAL BAY IN CHINA

JIANG Zhi-Bing, ZENG Jiang-Ning, CHEN Quan-Zhen(), LIAO Yi-Bo, SHOU Lu, XU Xiao-Qun, LIU Jing-Jing, HUANG Yi-Jun   

  1. Laboratory of Marine Ecosystem and Biogeochemistry, Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China
  • Received:2008-04-10 Accepted:2008-06-30 Online:2008-04-10 Published:2008-11-30
  • Contact: CHEN Quan-Zhen

摘要:

近年来, 随着电厂在河口和港湾等生态脆弱区和敏感区的急剧增多, 电厂冷却系统热冲击和加氯对浮游生物造成的伤害已成为沿海地区非常严峻的生态安全问题。为探明冷却系统升温和加氯联合作用对亚热带海区浮游植物的影响程度, 针对滨海电厂的实际运作情况, 在室内对采自浙江省乐清湾海域的四季浮游植物进行了不同水平的热冲击和加氯胁迫, 并观察了这些浮游植物细胞数量在15 d内的动态变化。结果表明, 热冲击、加氯和季节均显著影响浮游植物细胞数量的恢复(p<0.001), 其中, 加氯的影响最大, 季节次之, 热冲击影响最小, 但热冲击增强了氯对浮游植物的毒性。自然水温越高、升温幅度越大, 细胞数量恢复越慢。春、秋、冬季自然水温较低时, 升温4~12 ℃后, 细胞数量仅需1~6 d即可恢复到对照组水平; 夏季自然水温较高, 升温4~8 ℃后, 细胞数量需4~9 d恢复到对照组水平, 但升温12 ℃后, 细胞数量在15 d内未能恢复到对照组水平。加氯浓度越高, 细胞数量恢复越慢。加氯1.0~1.8 mg·L-1后, 浮游植物生长虽受影响, 但大多能在15 d内恢复; 而加氯5.6 mg·L-1后, 其生长受到完全抑制, 细胞数量在15 d内未恢复到对照组水平。

关键词: 热冲击, 氯胁迫, 海洋浮游植物, 恢复, 滨海电厂

Abstract:

Aims With the drastic increase in number of power plants adjacent to estuaries and bays, damage to plankton caused by thermal shock and chlorination in cooling systems has become a serious ecological problem in coastal areas. Presently, there are no criteria for temperature increment (ΔT) and chlorine dosage (CD) for coastal cooling systems in China. Our objectives are to 1) determine under which Δ T and CD that the phytoplankton biomass has potential to recover after passage through a cooling system and 2) supply a scientific basis for environmental risk assessment and standard formulation of Δ T andCD in cooling water.

Methods In four seasons from August 2006 to May 2007, we collected phytoplankton from the Yueqing Bay. In the laboratory, we stressed the phytoplankton at different Δ T (0, 4, 8, 12 ℃) and CD (0, 1.0, 1.8, 3.2, 5.6 mg·L-1). We then recorded the phytoplankton cell density (PCD) every 24 h in a stable culture for 15 d.

Important findings Both thermal shock and season significantly affected PCD recovery (p<0.001). The recovery period was longer with rising acclimation temperature (AT) and Δ T. When AT was low in spring, autumn and winter, PCD could recover to the control level in 1-6 d at the Δ T of 4-12 ℃. However, thermal shock would affect PCD more severely when AT was high in summer, as 4-9 d was needed for recovery at the Δ T of 4-8 ℃ and the resilience was lost at the Δ T of 12 ℃. Chlorination also significantly affected the PCD recovery (p<0.001) and had a greater impact than thermal shock. ThePCD recovery period was longer with increasing CD. Though PCD could generally restore during 15 d at the CD of 1.0-1.8 mg·L-1, it could not at the CDof 5.6 mg·L-1 in all seasons. Also, there was a synergistic effect between Δ T and CD that the effect of chlorine on PCD recovery was enhanced under temperature increase in the four seasons. Based on these data, current Δ T (6-12 ℃), CD (1-2 mg·L-1) and residual chlorine discharge level (0.15-0.25 mg·L-1) in coastal power plants do not severely affect subtropical phytoplankton biomass.

Key words: thermal shock, chlorine stress, marine phytoplankton, recovery, coastal power plant