In this study, a simple method for the simultaneous determination of trace metals(Cu, V, Co, Zn) in coastal seawater using the Mg(OH)2 coprecipitation inductively coupled plasma mass spectrometry(ICP-MS) was developed...In this study, a simple method for the simultaneous determination of trace metals(Cu, V, Co, Zn) in coastal seawater using the Mg(OH)2 coprecipitation inductively coupled plasma mass spectrometry(ICP-MS) was developed. This multi-element method enables the simultaneous extraction of four metals, particularly Co and V. The recoveries of Cu, Co, V and Zn after Mg(OH)2 coprecipitation were 73%, 96%, 94% and 92%, which means that our procedure was well-suited to the determination of these four trace metals. The detection limits were 3.81, 0.18, 6.09 and 1.91 nmol L-1, respectively. Then, applying this method to the simultaneous determination of these four metals in coastal water samples from the East China Sea revealed that the concentrations of Cu, Zn, Co and V were higher in bottom waters compared to water at other depths, and higher concentrations were generally observed at the Yangtze River estuary. Additionally, example vertical profiles of dissolved trace metal concentrations for the East China Sea in spring and autumn are compared. These findings indicate that Zn had the greatest seasonal variation followed by Cu, V and Co. For Zn and Co, the concentrations were higher during spring than during autumn. For Cu and V, the seasonal variation in the concentrations was opposite.展开更多
The autumn precipitation over southwest China is one of the main causes of meteorological disasters. Using observed monthly station rainfall data and HadISST and NCEP/NCAR analysis data, the impacts of three types of ...The autumn precipitation over southwest China is one of the main causes of meteorological disasters. Using observed monthly station rainfall data and HadISST and NCEP/NCAR analysis data, the impacts of three types of El Ni<span style="white-space:normal;">ñ</span>o-Southern Oscillation (ENSO) events on the boreal autumn rainfall over southwest China were determined. Over southwest China, autumn rainfall constitutes > 20% of the total annual rainfall and a marked decline in autumn rainfall commenced around 1990. During La Ni<span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span>a events, there is surplus (deficit) over the middle (northwest and southeast) of southwest China. In cnetral Pacific (CP) El Ni<span style="white-space:normal;">ñ</span>o events, the autumn rainfall anomaly shows a deficiency over China. The large-scale atmospheric circulation anomalies in the three ENSO categories also exhibit distinct characteristics. During CP El Ni<span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span>o autumns, the pressure anomaly over the North Pacific Ocean displays a “<img src="Edit_8b97423a-3df3-4458-ad74-b4f2006dd708.png" alt="" />” structure, with a high-pressure anomaly over the Asian continent. An anomalous cyclone appears over the western North Pacific (WNP). In EP El Ni<span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span>o autumns, the pressure anomaly over the North Pacific Ocean has a “<img src="Edit_3a7520ca-bfdd-4f81-a35c-4118a4616a5a.png" alt="" />” structure, with a low-pressure anomaly over the Asian continent. An anomalous anticyclone appears over the WNP and the 500-hPa anomalies are opposite to those of CP El Ni<span style="white-space:normal;"><span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span></span>o events. During La Ni<span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span>a autumns, the characteristics of circulation present<span style="font-family:;" "=""> </span><span style="font-family:Verdana;">the opposite structure to those of CP El Ni<span style="white-space:normal;"><span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span></span>o events. This work is of certain significance for an in-depth understanding</span><span style="font-family:Verdana;"> of</span><span style="font-family:Verdana;"> the impacts of ENSO on the autumn precipitation over southwest China.</span>展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 41140037, 41276069)the Young Scientist Award Science Foundation of Shandong, China (BS2010HZ026)the Open Science Funding of the Key Laboratory of the First Institute of Oceanography, SOA (MESE-2011-03)
文摘In this study, a simple method for the simultaneous determination of trace metals(Cu, V, Co, Zn) in coastal seawater using the Mg(OH)2 coprecipitation inductively coupled plasma mass spectrometry(ICP-MS) was developed. This multi-element method enables the simultaneous extraction of four metals, particularly Co and V. The recoveries of Cu, Co, V and Zn after Mg(OH)2 coprecipitation were 73%, 96%, 94% and 92%, which means that our procedure was well-suited to the determination of these four trace metals. The detection limits were 3.81, 0.18, 6.09 and 1.91 nmol L-1, respectively. Then, applying this method to the simultaneous determination of these four metals in coastal water samples from the East China Sea revealed that the concentrations of Cu, Zn, Co and V were higher in bottom waters compared to water at other depths, and higher concentrations were generally observed at the Yangtze River estuary. Additionally, example vertical profiles of dissolved trace metal concentrations for the East China Sea in spring and autumn are compared. These findings indicate that Zn had the greatest seasonal variation followed by Cu, V and Co. For Zn and Co, the concentrations were higher during spring than during autumn. For Cu and V, the seasonal variation in the concentrations was opposite.
文摘The autumn precipitation over southwest China is one of the main causes of meteorological disasters. Using observed monthly station rainfall data and HadISST and NCEP/NCAR analysis data, the impacts of three types of El Ni<span style="white-space:normal;">ñ</span>o-Southern Oscillation (ENSO) events on the boreal autumn rainfall over southwest China were determined. Over southwest China, autumn rainfall constitutes > 20% of the total annual rainfall and a marked decline in autumn rainfall commenced around 1990. During La Ni<span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span>a events, there is surplus (deficit) over the middle (northwest and southeast) of southwest China. In cnetral Pacific (CP) El Ni<span style="white-space:normal;">ñ</span>o events, the autumn rainfall anomaly shows a deficiency over China. The large-scale atmospheric circulation anomalies in the three ENSO categories also exhibit distinct characteristics. During CP El Ni<span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span>o autumns, the pressure anomaly over the North Pacific Ocean displays a “<img src="Edit_8b97423a-3df3-4458-ad74-b4f2006dd708.png" alt="" />” structure, with a high-pressure anomaly over the Asian continent. An anomalous cyclone appears over the western North Pacific (WNP). In EP El Ni<span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span>o autumns, the pressure anomaly over the North Pacific Ocean has a “<img src="Edit_3a7520ca-bfdd-4f81-a35c-4118a4616a5a.png" alt="" />” structure, with a low-pressure anomaly over the Asian continent. An anomalous anticyclone appears over the WNP and the 500-hPa anomalies are opposite to those of CP El Ni<span style="white-space:normal;"><span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span></span>o events. During La Ni<span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span>a autumns, the characteristics of circulation present<span style="font-family:;" "=""> </span><span style="font-family:Verdana;">the opposite structure to those of CP El Ni<span style="white-space:normal;"><span style="white-space:normal;"><span style="white-space:normal;">ñ</span></span></span>o events. This work is of certain significance for an in-depth understanding</span><span style="font-family:Verdana;"> of</span><span style="font-family:Verdana;"> the impacts of ENSO on the autumn precipitation over southwest China.</span>