[Distribution and bioavailability of nitrogen and phosphorus species in the urban dusts from Hefei City].

To find out the distribution and bioavailability of nitrogen (N) and phosphorus (P) species in the urban dusts of Hefei City, 52 samples were collected from impervious areas with six different urban land-use types. The contents of ammonia nitrogen (NH4(+) -N), nitrate nitrogen (NO3(-) -N), exchangeable P (Ex-P), Al-bound P (Al-P), Fe-bound P (Fe-P), occluded P (Oc-P), Ca-bound P (Ca-P), detrital apatite P (De-P), organic P (Or-P) as well as total nitrogen (TN) and total phosphorus (TP) were measured by sequential extraction methods. The studies on spatial distribution, correlation and bioavailability of nitrogen and phosphorus species were made according to the analyzed data.