Runoff, nutrients, sediment and salt yields in an irrigated watershed in southern Navarre (Spain)
Fecha
2018Autor
Versión
Acceso abierto / Sarbide irekia
Tipo
Artículo / Artikulua
Versión
Versión aceptada / Onetsi den bertsioa
Impacto
|
10.1016/j.agwat.2017.10.004
Resumen
The environmental impact of irrigated agriculture on water quality was assessed in Landazuria watershed (Navarre, northeast Spain), a 479.5 ha watershed with 53% of irrigated agricultural land. In the framework of a long-term monitoring program, precipitation and discharge were measured at 10-min
intervals and compound daily water samples were collected during the agricultural years (September t ...
[++]
The environmental impact of irrigated agriculture on water quality was assessed in Landazuria watershed (Navarre, northeast Spain), a 479.5 ha watershed with 53% of irrigated agricultural land. In the framework of a long-term monitoring program, precipitation and discharge were measured at 10-min
intervals and compound daily water samples were collected during the agricultural years (September to
August) 2007–2016, and analysed for nitrate (NO3−), phosphate (PO43−), sediment and total dissolved solids (TDS) concentrations. Typical agricultural management (including crop surfaces, irrigation and
fertilization rates) was obtained from inquiries to farmers. Concentration and yield of the studied variables presented a high degree of variation, both intra- and inter-annual. Median concentration for the entire study period were 185, <0.05, 31 and 2284 mg L−1 for NO3−, PO43−, sediment and TDS, respectively. NO3−-N and PO43−-P yields averaged 74 and 0.04 kg ha−1 year−1, respectively. NO3
−-N yield was higher than in other agricultural land uses in Navarre and in the order of magnitude of other irrigated areas in the Middle Ebro Valley. PO43−-P yield was in the same order of magnitude than in rainfed watersheds in Navarre but lower than in intensively grazed watersheds. Sediment yield was extremely variable, averaging 360 kg ha−1 year−1, with 44% of the total measured load recorded in a few days. It was in the lower range of those measured in Navarre for rainfed agriculture and similar to those estimated in other irrigated areas of the Middle Ebro River. TDS concentration presented a significant decreasing trend since available salts were being washed out, while TDS yield averaged 1.8 Mg ha−1 year−1. Long-term monitoring of irrigated areas is required to understand pollution processes in these agroecosystems and to adequately characterize the environmental impact of current agricultural practices on water quality, in order to implement, and adequately assess, measures to reduce agricultural pollution. [--]
Materias
Watershed,
Agricultural pollution,
Nitrate,
Phosphate,
Soil loss,
TDS
Editor
Elsevier
Publicado en
Agricultural Water Management 195 (2018) 120–132
Departamento
Universidad Pública de Navarra. Departamento de Proyectos e Ingeniería Rural /
Nafarroako Unibertsitate Publikoa. Landa Ingeniaritza eta Proiektuak Saila /
Universidad Pública de Navarra/Nafarroako Unibertsitate Publikoa. Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
Versión del editor
Entidades Financiadoras
This work benefited from the Research Project CGL2015-64284-C2-1-R (Ministerio de Economía y Competitividad). Daniel Merchán acknowledges the support of the “Juan de la Cierva – Formación” grant with code FJCI-2015-24920.