Abstract:

The authors analyzed the spatial distribution of phosphorus in sediments to control the the eutrophication. Thirteen samples in surface sediment and surface water were collected, sequential extraction methods was used to acquire NH₄Cl-P, BD-P, NaOH-P, HCl-P, and Res-P, and the spatial distribution characteristics of these different forms of phosphorus and their impact on soluble phosphate were analyzed. The results indicated that the contents of different P fractions in the sediments varied greatly. The total P (TP) contents ranged from 808.5 to 1 698.7 mg·kg^-1. Phosphorus contents in NH₄Cl-P, BD-P, NaOH-P, HCl-P and Res-P ranged from 8.1 to 31.1, 41.9 to 84.9, 151.6 to 348.2, 312.2 to 819.9 and 226.8 to 1 003.0 mg·kg^-1, which represented 0.65%-1.85%, 3.19%-6.57%, 10.8%-24.34%, 20.26%-52.18% and 24.41%-58.33% of the total P, respectively. The total dissolved P of pore water has high correlation with the NH₄Cl-P, BD-P, NaOH-P in sediments, with 0.892, 0.848, 0.749 correlation coefficient. The results showed NH₄Cl-P, BD-P, NaOH-P as the main source of P release control.

Key words: Haihe River, sediments, phosphorus, speciation, release, pore water