Irrigation-induced nitrate losses assessed in a Mediterranean irrigation district
| Autor: | John Ryan, Wolfgang Albert Flügel, Yunus Bulbul, Burak Tilkici, Hayriye Ibrikci, Mahmut Çetin, Ebru Karnez |
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| Přispěvatelé: | Çukurova Üniversitesi |
| Jazyk: | angličtina |
| Rok vydání: | 2015 |
| Předmět: |
Mediterranean climate
Irrigation Nitrate loss Soil Science engineering.material Irrigation district Temporal nitrate variability Crop chemistry.chemical_compound Agronomy Nitrate chemistry Productivity (ecology) Irrigation return flow engineering Environmental science Mediterranean agriculture Fertilizer Drainage Agronomy and Crop Science Earth-Surface Processes Water Science and Technology |
| Popis: | Irrigated agriculture is crucial for productivity of major crops (mainly cereals) grown in Mediterranean countries, where extended and prolonged drought conditions adversely impact productivity. Under such conditions, irrigation and rainfall events combined with nitrogen (N) fertilization can induce nitrate (NO3) losses in irrigation return flows (IRFs). Such water-induced NO3 losses in IRFs were assessed during the 2007-2010 hydrological years in the 9495ha of the Akarsu Irrigation District (AID) of southern Turkey, with daily monitoring at three drainage gauging stations to quantify flow rates, NO3 concentrations and loads. Climatic data, soil characteristics, fertilizer N application rates to major crops, cropping patterns, and irrigation and rainfall depths were also recorded. Nitrate concentrations were higher in IRFs during winter months, ranging between 37 and 44mgNO3L-1 on average, compared to the concentrations in the irrigation season (10-23mgNO3L-1). Since most of the fertilizer N was applied in winter and early spring to wheat (2/3 of 195kgNha-1) and first crop corn (1/3 of 340kgNha-1) as preplant and surface applications; NO3 concentrations were high during these seasons because of the limited N consumption of these crops in their early growth stages. However, the NO3 load distributions in winter and summer months were similar. Annual loads of 39.7, 29.3, 55.3 and 55.2kg NO3-Nha-1 were measured in the 2007-2010 IRFs, respectively, with 45 to 57% occurring during the irrigation seasons. The consistent high NO3 over 4 years point to the potential to reduce losses and associated N pollution through better crop, irrigation and N fertilizer management. Well-established fertilizer and irrigation water management plans are critical to reduce NO3 pollution risks in Mediterranean irrigated lands. © 2014 Elsevier B.V. Sixth Framework Programme: INCO-CT-2005-015031 Firat University Scientific Research Projects Management Unit TUBITAK-108O582 Authors gratefully acknowledge funding for this work by the European Commission reseach project in the context of FP6 with project acronym QUALIWATER (Project No. INCO-CT-2005-015031), IntenC project acronym MedSalin (TUBITAK and German-BMBF, TUBITAK-108O582) and partial support was received from Cukurova University Academic Research Projects Unit (Project No. ZF2006KAP1 and ZF2009KAP3). We are also thankful to Dr. Ramon Aragües at Departamento de Suelos y Riegos, CITA, Zaragoza, Spain for his in-depth review and suggestions for improvement of the manuscript. |
| Databáze: | OpenAIRE |
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