Saniewski Michał
Institute of Meteorology and Water Management, National Research Institute, Maritime Branch, Waszyngtona 42, 81-342 Gdynia, Poland.
ScientificWorldJournal. 2013 Nov 12;2013:276098. doi: 10.1155/2013/276098. eCollection 2013.
The Baltic Sea is one of the most contaminated seas by the radioactive isotope of strontium in the world; therefore the activity of ⁹⁰Sr is regularly controlled. Due to that fact, seawater samples for ⁹⁰Sr determination were collected at 16 stations located in the southern Baltic Sea between 2005 and 2010. In this period average activity of ⁹⁰Sr was 7.8 Bq m⁻³ and varied within the range from 3.0 Bq m⁻³ to 11.9 Bq m⁻³. Because the higher activity of ⁹⁰Sr was measured in the Baltic Sea than in the North Sea and rivers, inflows from the North Sea and the riverine runoff decreased ⁹⁰Sr activity in the Baltic Sea. The average ⁹⁰Sr activity in the bottom water along the offshore profile was 18% lower than that in the surface water and it was caused by an inflow of salt water from the North Sea. In the Vistula River mouth the average activity of ⁹⁰Sr in the surface water was about 15% lower than the average activity in the bottom waters. Coastal areas, relatively shallow with good mixing condition in the water column, were characterized by low variability in ⁹⁰Sr activity.
波罗的海是世界上受锶放射性同位素污染最严重的海域之一；因此，对⁹⁰Sr的活度进行定期监测。基于这一事实，于2005年至2010年期间在波罗的海南部的16个站点采集了用于测定⁹⁰Sr的海水样本。在此期间，⁹⁰Sr的平均活度为7.8 Bq m⁻³，变化范围在3.0 Bq m⁻³至11.9 Bq m⁻³之间。由于在波罗的海测得的⁹⁰Sr活度高于北海和河流，北海的流入量和河流径流降低了波罗的海中⁹⁰Sr的活度。沿近海剖面底部水体中⁹⁰Sr的平均活度比表层水体低18%，这是由北海盐水的流入造成的。在维斯瓦河河口，表层水体中⁹⁰Sr的平均活度比底部水体的平均活度低约15%。沿海地区相对较浅，水柱混合条件良好，其⁹⁰Sr活度变化较小。
