Data/hora: 10/06/2024 06:44:52

Provedor de dados: | 18
País: | United Kingdom
Título: | Assessment of Phosphorus Retention in   Irrigation Laterals
Autores: | Ippolito, J.A.; Nelson, N.O.
Data: | 2013-11
Ano: | 2013
Palavras-chave: | Drainage water (see Percolation water); Nutrients.
Resumo: | Irrigation  laterals  transport  irrigation  return  flow,  including  water,  sediment, and dissolved nutrients, such as phosphorus (P), back to surface water bodies. Phosphorus transformations during transport can affect both P bioavailability and the best management practices selected to minimize P inputs to waters of the United States. The objective of this study  was  to  determine  P  retention  in  three  irrigation  laterals.  Soluble  reactive  P  (SRP) concentrations in lateral waters were increased from 0.08 to 0.25 mg L -1  (0.08 to 0.25 ppm) by constantly injecting a phosphate (PO4) solution for 2.5 hours. Bromide (Br) was used as a conservative tracer to determine dilution effects. Water was sampled at 10-minute intervals, beginning 30 minutes prior to injection and 120 minutes following injection, at one upstream location and various downstream locations to approximately 1,550 m (~1 mi) from injection  sites. When  at  steady  state,  SRP  concentrations  only  decreased  by  5%  over  the lengths studied, equating to P uptake lengths of over 18 km (11.2 mi), which was one to two orders of magnitude greater than natural streams; the linear SRP uptake rate was 0.011 mg L -1  km -1  (0.018 ppm mi -1 ). Longer P uptake lengths and lower uptake rates in irrigation laterals, as compared to natural streams, may be due to the elevated sediment equilibrium P concentration, greater water velocities, and removal of vegetation causing a reduction in frictional resistance. Reducing water velocities should optimize irrigation lateral conditions to reduce uptake length and maximize P uptake.
Tipo: | Article

Identificador:

http://eprints.nwisrl.ars.usda.gov/1513/1/1477.pdf

Ippolito, J.A. and Nelson, N.O. (2013) Assessment of Phosphorus Retention in Irrigation Laterals. Journal of Soil and Water Conservation. 68(6):450-459. November 2013.

Relação: | http://eprints.nwisrl.ars.usda.gov/1513/
Formato: | application/pdf