title: [Temporal and spatial characteristic of nitrogen and phosphorus output in the suburb watershed around the Baihua Lake].
abstract: Identification of the main pollutants and sources has important practical significance for the control and management of water quality in Guiyang's surrounding river areas. Based on the continuous field observation of the experiment from July, 2010 to April, 2011, this paper studies the concentration of nitrogen and phosphorus loss characteristics of Maixi river watershed, which is near to Guiyang's important water source-Baihua Lake reservoir, so as to provide a reference for Guiyang suburban small watershed source pollution control. The existence of various sources and sinks in this river basin makes great changes of nitrogen output in each sample point at different times, from upstream to downstream. Although different forms of nitrogen content and phosphorus content in water at each sampling point changes with time, it still presents a certain regularity on the whole. The total nitrogen and nitrate nitrogen in July 2010 are above normal level, and the ammonia nitrogen, nitrate nitrogen and total phosphorus are at high levels in October 2010 and December. The differences of various forms of nitrogen and phosphorus content in water at each sampling point decrease from upstream to downstream. The content of TN decreases from 3.297 mg x L(-1) to 2.793 mg x L(-1), and the content of TP decreases from 0.136 mg x L(-1) to 0.098 mg x L(-1). Contrast to the upstream, the nitrogen and phosphorus content in the downstream estuary decreases significantly. But the change is not obvious and the content of ammonia nitrogen rises slightly compared with the middle reaches. From the perspective temporal and spatial variation characteristics of nitrogen and phosphorus output in the basin, the nitrogen, especially ammonia nitrogen and nitrate, has a higher risk of getting into the Baihua Lake by river runoff. The results of the study can provide a reference for the governance of nitrogen and phosphorus loss in the watershed around the Baihua Lake.
authors.forename: Yuan-song
authors.initials: YS
authors.lastname: Feng
authors.forename: Tao
authors.initials: T
authors.lastname: Lin
authors.forename: Qing-yuan
authors.initials: QY
authors.lastname: Yang
mesh_terms: D002681:China; D004784:Environmental Monitoring; D063366:Estuaries; D005618:Fresh Water; D060106:Lakes / Q000737:chemistry*; D009584:Nitrogen / Q000032:analysis*; D010758:Phosphorus / Q000032:analysis*; D045483:Rivers; D062211:Spatio-Temporal Analysis; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D014874:Water Pollutants, Chemical; D010758:Phosphorus; D009584:Nitrogen