香港近岸海域营养盐结构特征及其对浮游植物生长的影响  

TEMPORAL AND SPATIAL DISTRIBUTION OF NUTRIENTS AND CHL A IN THE COASTAL AREA OF HONG KONG

作　　者：宋秀贤[1,2] 俞志明[1] 殷克东[2] 钱培元[2] 

机构地区：[1]中国科学院海洋研究所海洋生态与环境科学重点实验室,青岛266071 [2]香港科技大学生物系

出　　处：《海洋与湖沼》2013年第4期846-852,共7页Oceanologia Et Limnologia Sinica

基　　金：国家973项目;2010CB428706号;国家自然科学基金创新群体项目;41121064号;国家自然科学基金项目;41276115号;香港科技大学PREPP项目的支持

摘　　要：本文利用2000年3月至2001年5月在香港近岸牛尾海海域(Porter Shelter,Hong Kong)14个航次的现场调查数据,对水体中营养盐组成结构和叶绿素a含量进行了分析研究。结果表明,该海域表层和底层水体中溶解无机氮(DIN,包括NO3-N+NO2-N,NH4+-N)平均浓度范围分别为1.24—9.72 mol/L及1.30—7.49 mol/L,均表现为冬季最高、秋季最低。不同季节表层水体中PO43-P浓度范围为0.14—0.46 mol/L,夏季平均浓度最底;底层PO43-P浓度变化不大,但夏季仍低于其他季节。不同季节表层和底层水体中SiO32-Si的变化趋势基本相似,平均浓度范围分别为7.80—18.47 mol/L和8.13—16.87 mol/L,均在冬季最高,其它季节差别不大。叶绿素a分析结果显示,表层水体高生物量大多出现在夏末秋初季节(如8月份),春季(4月份)次之;底层水体叶绿素a秋季最高,夏季次之。进一步分析了该海域营养盐对浮游植物生长的可能限制因子,结果表明表层水体春季呈现氮–磷协同限制的可能性、夏季磷限制较明显,秋季表现为显著的氮限制。底层水体春、夏季呈现氮–磷协同限制的趋势,秋季也表现为明显的氮限制。冬季磷酸盐浓度相对氮、硅的含量较低,但各种营养盐相对于浮游植物生长的最低阈值都比较丰富,所以,冬季表、底层水体中营养盐对浮游植物的生长均不形成限制因素。另外,除了夏季表层水体外,其它季节该水域浮游植物生长受溶解无机硅限制的可能性较少。Regular cruise from March 2000 to May 2001 was conducted monthly （or twice in one month） to investigate the nutrients and chl a in the coastal area of Hong Kong （Porter Shelter, HK）. Both of the surface and bottom water were selected to determine the nutrient concentrations and chl a distribution in different seasons. The results show that the annual average concentration of total dissolved inorganic nitrogen （DIN including NO3？-N＋NO2？-N, NH4＋-N） were 1.24—9.72mol/L and 1.30—7.49mol/L in surface and bottom water, respectively. The highest value of DIN was in winter and the lowest was in autumn during the investigation period. PO43？-P concentration in surface water changed from 0.14 to 0.46mol/L in different seasons （minimum in summer）. The bottom PO43？-P concentration was more steadily than in the surface water. However, it still showed a decrease tendency in summer days. As for SiO32？-Si, the average concentrations changed in same characteristics in both the surface and bottom waters in range of 7.80—18.47 and 8.13—16.87mol/L, respectively. The highest SiO32？-Si concentration was in winter, and in other season there was no obvious difference. The results of chl a in different seasons revealed that in surface water the highest biomass was in summer （August） and the second peak value was in spring. Chl a concentration in bottom water was the highest in autumn and summer was following. Further analysis of the nutrients limitation for phytoplankton growth showed that in surface water there was a possibility of N and P cooperation limiting in spring. Similarly, it showed P-limitation in summer and N-limitation in autumn obviously. However, in bottom water it revealed that there was a trend of N and P cooperative limitation during spring and summer. And it also showed N-limitation in autumn obviously. Although PO43？-P concentration was lower than those of nitrogen and silicate concentrations in winter, all nutrient concentrations were higher than the minimal value of phyto

关 键 词：香港近岸海域 营养盐 限制因子 叶绿素A 

分 类 号：P734.4[天文地球—海洋化学]