The effect of irrigation management on pasture yield and nitrogen loss

4 June 2019

Global food production has intensified over the past century with the help of irrigation and fertiliser. While the benefits of irrigation on yield are well established – and include greater reliability of production and improved quality of products – the environmental consequences are poorly quantified. In New Zealand irrigation has risen significantly in past decades, making this an important area of research.

Plant & Food Research and AgResearch scientists analysed six different irrigation scenarios in New Zealand farms to assess the impacts of irrigation management on pasture production and Nitrogen (N) losses. 

The scientists employed the APISM (Agricultural Production Systems sIMulator) modelling framework, an advanced simulator of agricultural systems, which is a cost-effective way of identifying the impact of different irrigation management practices on a range of soils. 

The study found that in shallow soils more frequent irrigation resulted in higher pasture production, but also resulted in higher N losses.  In deep soils pasture production was not affected by irrigation frequency and less frequent irrigation and maintaining soil water deficits could be used to reduce cost and N losses without compromising productivity.


Journal Reference:

Vogeler, I, Thomas, S, van der Weerden, T (2019) Effect of irrigation management on pasture yield and nitrogen losses. Agricultural Water Management DOI: 10.1016/j.agwat.2019.01.022

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