Conservation Agriculture and Its Impact on Hydraulics of Surface Irrigation Methods

Document Type : review paper

Authors

• Seyed Abolghasem Haghayeghi Moghadam ¹
• Hossein Ansari ²

¹ Ph.D. Student Water Engineering Department, Ferdowsi University of Mashhad, Iran

² Associate Professor, Ferdowsi University of Mashhad, Iran

10.22067/jwsd.v1i1.34604

Abstract

Conservation agriculture (CA) is a series of measures which include retention of adequate levels of crop residues on the soil surface, proper crop rotations and reductions in tillage as much as possible so that their application conserve time, energy and promote soil and water resources. Among impacts of CA that would affect hydraulics of surface irrigation methods are variations in roughness coefficient and soil infiltration. In present research the increase in roughness coefficient and soil infiltration rate were determined respectively 35% and 25% in CA conditions. Results of using SIRMOD model for simulation of surface irrigation in CA conditions showed that advanced water time would increase averagely 37.2% in CA comparing to conventional agriculture. This incline can be contributed to   the increase in roughness coefficient due to crop residues on the farm surface. Modification of tillage method from conventional to conservation didn’t change the application and irrigation efficiency. Water distribution uniformity in farm decreased 9% by applying CA method. CA could bear 36% reduction in run off tail water that which is a good advantage of this method. On the other hand, CA increased the deep percolation under root development zone by 54% on average.    

Keywords

• conservation agriculture
• surface irrigation
• tillage
• crop residues

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