摘要
中国第22次南极科学考察(2005年11月至2006年3月)期间,测定了南极普里兹湾海域5个站位的从表层至150 m水深的不同层位水样中溶解态和颗粒态234Th,238U的放射性比活度以及颗粒有机碳.利用234Th/238U在上层水体中的不平衡,计算了南极普里兹湾上层水体中234Th的平均停留时间和输出通量.结果显示,随着纬度的增加,上层水体中颗粒态和溶解态234Th的平均停留时间总体趋向减小,并在中纬度站位出现了最低值,分别为1~8和29~48 d,而颗粒态和溶解态234Th的输出通量则在中纬度站位出现了最大值,分别为21~38和26~39 dpm/(m3.d).运用箱型清除模式,利用两种不同的方法估算了各水柱中从真光层底部输出的POC通量,平均值分别达到104.7 mmol/(m2.d)(E法)和120.6 mmol/(m2.d)(B法),表明南极普里兹湾夏季存在很高的新生产力,它将会对该海域碳的生物泵过程产生重要作用.
Dissolved and particulate ^234 Th, particulate organic carbon in the upper 150 m of water columns from five stations in the Prydz Bay, Southern Ocean were determined during the 22nd Chinese National Antarctic Research Expedition（from Nov. 2005 to Mar. 2006）. The disequilibria between ^234Th and its parent ^238U in upper layer was used to derive the average residence time of ^234 Th, which decreased along with the latitude toward south with minimum values, respectively 1-8 d for particulate ^234Th and 29- 48 d for dissolved ^234 Th, appeared at the medium latitude station, and the export fluxes of ^234Th were calculated too and max values, respectively 21-38 dpm/（m^2· d）for particulate^234Th and 26-39 dpm/（m^2· d） for dissolved ^234 Th, appeared at the same station. The export fluxes of particulate organic carbon at different water columns were derived by two methods with irreversible scavenging model, and the average value were 104. 7 mmol/（m^2 · d）（E method） and 120. 6 mmol/（ m^2· d）（B method）, respectively, which meant in summer relatively high new production existed in the Prydz Bay where would play a significant role as CO2 sink.
出处
《海洋学报》
CAS
CSCD
北大核心
2007年第4期69-76,共8页
基金
国家自然科学基金重点项目(40531007)
国家自然科学基金项目(4040601440276001)
国家社会公益基金项目(2004DIB5178)
福建省自然科学基金计划资助项目(2006J0287)
