[HCG27-P07] Modeling and prediction of pollutant load outflow from the Yangtze River Basin
Keywords:Pollutant load, Nitrogen, Phosphorus, Yangtze river basin
The model was calibrated by the observation data during 2004-2006 and validated by the data during 2008-2010. The validation showed that the monthly flow variations were modeled accurately, although the correlations were lower for the downstream area than for the upstream area, and the modeling ability for phosphorous load was lower than that for nitrogen load. We used the validated model to estimate the distribution dynamics of the pollutant load of both nitrogen and phosphorus outflow, such as the total nitrogen (T-N), nitrate nitrogen (NO3-N), nitrite nitrogen (NO2-N), ammonium nitrogen (NH3-N), total phosphorous (T-P) and dissolved phosphorus (DIP) from the the Yangtze River. The simulation results showed that in the decade from 2001 to 2010, the amount of NO3-N increased by 2.9 times, NO2-N increased 3.2 times, and NH3 N increased 3 times compared to values from the 1980s (Duan et al., 2000). In order to verify these estimated results further, we also measured the water quality at the Datong hydrological station from 2011 to 2014 (Table 1), and found that the average annual amount of transported NO3-N, NO2-N, and NH3-N still keep on the high level condition, and increased by 2.2 times, 3.2 times, and 3.5 times respectively compared to values from the 1980s (Duan et al., 2000). Therefore, we conclude that the pollutant load outflow had remained at a high level during 2000-2014.
This study is supported by the project "Analyses of the impact of the anthropogenic pollution on the ecosystem of the East China Sea and the sea around Japan" (2011-2015), funded by National Institute for Environmental Studies, Japan.