As the result of seasonal fluctuation of water, the total Hg concentration of water and sediment would be degressive in sequence of low water, flush time and ordinary level.

水位随季节周期性消落，将导致水体相和沉积物相中的总汞浓度按枯、丰、平顺序依次递减。

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The Baltic Sea is semi-enclosed, so it takes a long time to flush out toxins.

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According to the Associated Press, the synchronised flush will now take place at the same time twice a week - on Mondays and Thursdays - though residents will of course be able to flush their toilets at other times too.

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This is time for the second flush - or harvest - of tea in the region, which fetches high prices in European markets.

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