Fabio Corradini1, Francisco Nájera2, Manuel Casanova2, Yasna Tapia2, Ranvir Singh3, Osval do Salazar4. 1. Programa de Magíster en Manejo de Suelos y Aguas, Facultad de Ciencias Agronómicas, Universidad de Chile, Casilla, 1004, Santiago, Chile. 2. Departamento de Ingeniería y Suelos Facultad de Ciencias Agronómicas, Universidad de Chile, Casilla, 1004, Santiago, Chile. 3. Institute of Agriculture and Environment, Massey University, Palmerston North, 4410, New Zealand. 4. Departamento de Ingeniería y Suelos Facultad de Ciencias Agronómicas, Universidad de Chile, Casilla, 1004, Santiago, Chile. osalazar@uchile.cl.
Abstract
There are concerns about the impact of maize cultivation with high applications of nitrogen (N) and phosphorus (P) on water quality in surface waters in Mediterranean Central Chile. This study estimated the contribution of N and P from maize fields to nearby drainage channels and evaluated the effects in water quality. An N and P budget was drawn up for three fields managed with a maize-fallow system, El Maitén (20.7 ha), El Naranjal (14.9 ha) and El Caleuche (4.2 ha), and water quality variables (pH, EC, dissolved oxygen, total solids, turbidity, NO3-N, NH4-N, PO4(3-), COD, total N, total P and sulphate) were monitored in nearby drainage channels. The N and P balances for the three fields indicated a high risk of N and P non-point source pollution, with fertiliser management, soil texture and climate factors determining the temporal variations in water quality parameters. Elevated levels of NH4-N and PO4(3-) in the drainage channels were usually observed during the winter period, while NO3- concentrations did not show a clear tendency. The results suggest that excessive slurry application during winter represents a very high risk of N and P runoff to drainage channels. Overall, great emphasis must be placed on good agronomic management of fields neighbouring drainage channels, including accurately calculating N and P fertiliser rates and establishing mitigation measures.
There are concerns about the impact of n class="Species">maize cultivationpan> with high applicationpan>s of pan> class="Chemical">nitrogen (N) and phosphorus (P) on water quality in surface waters in Mediterranean Central Chile. This study estimated the contribution of N and P from maize fields to nearby drainage channels and evaluated the effects in water quality. An N and P budget was drawn up for three fields managed with a maize-fallow system, El Maitén (20.7 ha), El Naranjal (14.9 ha) and El Caleuche (4.2 ha), and water quality variables (pH, EC, dissolved oxygen, total solids, turbidity, NO3-N, NH4-N, PO4(3-), COD, total N, total P and sulphate) were monitored in nearby drainage channels. The N and P balances for the three fields indicated a high risk of N and P non-point source pollution, with fertiliser management, soil texture and climate factors determining the temporal variations in water quality parameters. Elevated levels of NH4-N and PO4(3-) in the drainage channels were usually observed during the winter period, while NO3- concentrations did not show a clear tendency. The results suggest that excessive slurry application during winter represents a very high risk of N and P runoff to drainage channels. Overall, great emphasis must be placed on good agronomic management of fields neighbouring drainage channels, including accurately calculating N and P fertiliser rates and establishing mitigation measures.
Entities:
Keywords:
Fertilisation; Non-point source pollution; Pig slurry; Water quality
Authors: Alipio Bermúdez-Couso; David Fernández-Calviño; Manuel Ali Álvarez-Enjo; Jesús Simal-Gándara; Juan Carlos Nóvoa-Muñoz; Manuel Arias-Estévez Journal: Sci Total Environ Date: 2013-06-02 Impact factor: 7.963
Authors: M J Bowes; J T Smith; C Neal; D V Leach; P M Scarlett; H D Wickham; S A Harman; L K Armstrong; J Davy-Bowker; M Haft; C E Davies Journal: Sci Total Environ Date: 2011-05-31 Impact factor: 7.963
Authors: Jaime Pizarro; Pablo M Vergara; José A Rodríguez; Pedro A Sanhueza; Sergio A Castro Journal: J Hazard Mater Date: 2009-10-20 Impact factor: 10.588
Authors: Amy T Austin; Laura Yahdjian; John M Stark; Jayne Belnap; Amilcare Porporato; Urszula Norton; Damián A Ravetta; Sean M Schaeffer Journal: Oecologia Date: 2004-02-24 Impact factor: 3.225