2007年夏季北部湾生态与环境要素分布规律研究

为获得北部湾生态要素分布规律更全面的认识,本文基于北部湾海表层温度、盐度和有关生态参数的遥感数据,利用2007年"908"专项调查资料,结合海流数值计算结果,分析了2007年夏季(6-8月)的海表层温度、盐度、叶绿素a浓度和颗粒有机碳(Particulate Organic Carban,POC)、颗粒无机碳(Particulate Inorganic Carban,PIC)浓度的分布态势并给予合理的动力机制解释:(1)北部湾表层叶绿素a浓度呈明显的自东向西、由近岸向湾中部逐渐递减的态势,高值区为琼州海峡、广西沿岸、越南沿岸和海南岛西南侧近海海域;(2) POC和PIC空间分布特征与叶绿素a相似,低值区均主要集中在湾口水交换较快区域;(3)入侵高盐水的33.5 PSU等值线最北可达到21°N;湾内存在一个上升流区域形成的高盐核心;(4)北部湾水温的高值区分布在广西沿岸和越南沿岸的浅水区;(5)叶绿素a、POC和PIC高值区与沿岸径流有关;(6)海南岛西南部叶绿素a、POC和PIC的高值区与上升流有关。上述分析虽然只是2007年一年的结果,但是结果却具有普遍的意义。

Study on the Distribution Rule of Ecological and Environmental Elements in Beibu Gulf in Summer of 2007

In order to obtain a more complete and comprehensive understanding of the distribution rule of ecological elements in Beibu Gulf, the distribution of sea surface temperature, salinity, chlorophyll-a, particulate organic carbon (POC) and particulate inorganic carbon (PIC) in summer (June, July, August) of 2007 were analyzed and a rational explanation of the dynamic mechanism was given based on remote sensing data of sea surface temperature (SST), sea surface salinity (SSS) and ecological parameters in Beibu Gulf and dataset collected from project "908" and combined with the numerical model results of current field. (1) The concentration of chlorophyll-a in the surface layer of Beibu Gulf was gradually decreasing from east to west, from the coastal area to the middle of the Gulf. The high-value areas were Qiongzhou Strait, Guangxi Coast, Vietnam Coast, and the coastal waters on the southwest side of Hainan Island. (2)The spatial distribution characteristics of POC and PIC were similar to those of chlorophyll-a, and the low-value areas were mainly concentrated in areas with fast water exchange in the entrance of bay. (3) The 33.5 psu contour that invaded the high salt water far reached the north of the Gulf until 21°N. There was a high salt core formed in an upwelling area within the bay. (4) High temperature areas of Beibu Gulf were distributed in the shallow waters along the coast of Guangxi and Vietnam. (5) High values of chlorophyll-a, POC and PIC were related to coastal runoff. (6) High values of chlorophyll-a, POC and PIC in the southwestern part of Hainan Island are related to the upwelling. Although the above analysis is only a one-year result in 2007, the result is of universal significance.