【摘 要】
：
Based on the results of water sample measurements of nutrient concentrations at theDatong Station of the Changjiang River from 1998 to 1999, combined with histo
【机 构】
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Inst. of Geographic Sciences and Natural Resources Research, Beijing 100101, China
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Based on the results of water sample measurements of nutrient concentrations at theDatong Station of the Changjiang River from 1998 to 1999, combined with historical data of waterquality, seasonal variations of nutrient concentrations and nutrient transports are discussed. Thefollowing results have been obtained: (1) the fluxes of the nitrate nitrogen, ammonium nitrogen andnitrite nitrogen increased by time-series from 1962 to 1990, even if runoff volume had a littlevariation; (2) the concentrations and fluxes of the dissolved inorganic mtrogen (DIN) and dissolvedinorganic phosphorus (DIP) increased notably with time, but those of the dissolved silicon (DSI)decreased pronouncedly; and (3) the concentrations and fluxes changed synchronously with timebetween the Datong Station and the Changjiang Estuary.
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