Plants and nitrous oxide emissions
NZAGRC research aims to identify forage plants that could reduce the quantity of nitrogen excreted by livestock and/or influence microbial processes in the soil that cause nitrous oxide emissions.
We are undertaking a review of the NZAGRC nitrous oxide research programme. New projects will be listed here in the future.
In New Zealand, nitrous oxide emissions are primarily driven by the quantity of nitrogen excreted by grazing ruminants. See the Science of nitrous oxide page for information on how nitrogen leads to nitrous oxide emissions.
International and New Zealand-based research has shown that different feeds can change both the quantity of nitrogen deposited in urine and the chemical makeup of the urine. In addition, research has demonstrated that some plants help to reduce nitrous oxide emissions by directly influencing nitrification and denitrification processes in the soil.
NZAGRC-funded research conducted between 2017 and 2019, in association with the industry-led Forages for Reduced Nitrate Leaching Programme, found that plantain holds particular promise with regard to each of these effects. However, subsequent field trials have yielded inconsistent results.
Further work is underway to better understand the factors affecting the efficacy of plantain, including the minimum plantain proportion required in the diet and the sward, as well as the effect of sward age, soil type and climate on nitrous oxide emissions.