727
However , sediment laminations from Stockholm Archipelago , an indicator of past hypoxia , ( 17 ) have been shown to be a recent phenomenon with very few areas with laminated sediments prior to 1900 . 17 , 18 The long - term millennial trends in coastal hypoxia remain unknown , although hypoxia has occurred intermittently throughout the last 8000 years in offshore deep waters of the Baltic Sea . ( 10 ) Further sediment studies are necessary , similar to those carried out in the open Baltic Sea , ( 10 ) to ascertain how far back in time hypoxia was observed in the coastal zone .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Anatomy 
Text: {0} 
Answer:
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