We assessed nutrient characteristics, distributions and fractions within the disturbed and undisturbed sediments at four sampling sites within the mainstream of Haihe River. The river sediments contained mostly sand ...We assessed nutrient characteristics, distributions and fractions within the disturbed and undisturbed sediments at four sampling sites within the mainstream of Haihe River. The river sediments contained mostly sand （ 60%）. The fraction of clay was 3%. Total nitrogen （TN） and total phosphorus （TP） concentrations ranged from 729 to 1922 mg/kg and from 692 to 1388 mg/kg, respectively. Nutrient concentrations within the sediments usually decreased with increasing depth. The TN and TP concentrations within the fine sand were higher than for that within silt. Sediment phosphorus fractions were between 2.99% and 3.37% Ex-P （exchangeable phosphorus）, 7.89% and 13.71% Fe/Al-P （Fe, Al oxides bound phosphorus）, 61.32% and 70.14% Ca-P （calcium-bound phosphorus）, and 17.03% and 22.04% Org-P （organic phosphorus）. Nitrogen and phosphorus release from sediment could lead to the presence of 21.02 mg N/L and 3.10 mg P/L within the water column. A river restoration project should address the sediment nutrient stock.展开更多
Polycyclic aromatic hydrocarbons（PAHs）are attracting concern because of their potential toxicity,posing serious threats to health of humans and ecosystems（Kim et al.,2013;Zhao et al.,2016）.Generally,similar to oth...Polycyclic aromatic hydrocarbons（PAHs）are attracting concern because of their potential toxicity,posing serious threats to health of humans and ecosystems（Kim et al.,2013;Zhao et al.,2016）.Generally,similar to other contaminants＇behaviors（Wu et al.,2001;Zhang et al.,2007,2008;Lu et al.,2009）,PAHs result from natural organic matter and activities of humans,the latter＇s contribution usually outweighing the inputs from other sources（Fernández et al.,2000;Srogi,2007）.展开更多
基金supported by the National Natural Sci- ence Foundation of China (No. 51079068)the Natural Science Foundation of Tianjin (No. 09ZCGYSF00400, 08FDZDSF03402)+1 种基金the National Key-Projects of Water Pollution Control and Prevention (No. 2008ZX07314-005- 001, 2009ZX07209-001)funded by The Royal Society
文摘We assessed nutrient characteristics, distributions and fractions within the disturbed and undisturbed sediments at four sampling sites within the mainstream of Haihe River. The river sediments contained mostly sand （ 60%）. The fraction of clay was 3%. Total nitrogen （TN） and total phosphorus （TP） concentrations ranged from 729 to 1922 mg/kg and from 692 to 1388 mg/kg, respectively. Nutrient concentrations within the sediments usually decreased with increasing depth. The TN and TP concentrations within the fine sand were higher than for that within silt. Sediment phosphorus fractions were between 2.99% and 3.37% Ex-P （exchangeable phosphorus）, 7.89% and 13.71% Fe/Al-P （Fe, Al oxides bound phosphorus）, 61.32% and 70.14% Ca-P （calcium-bound phosphorus）, and 17.03% and 22.04% Org-P （organic phosphorus）. Nitrogen and phosphorus release from sediment could lead to the presence of 21.02 mg N/L and 3.10 mg P/L within the water column. A river restoration project should address the sediment nutrient stock.
文摘Polycyclic aromatic hydrocarbons（PAHs）are attracting concern because of their potential toxicity,posing serious threats to health of humans and ecosystems（Kim et al.,2013;Zhao et al.,2016）.Generally,similar to other contaminants＇behaviors（Wu et al.,2001;Zhang et al.,2007,2008;Lu et al.,2009）,PAHs result from natural organic matter and activities of humans,the latter＇s contribution usually outweighing the inputs from other sources（Fernández et al.,2000;Srogi,2007）.
