Impacts of pasture species and ruminant urine on N2O emissions and nitrogen transforming microbial communities in soil mesocosms. Issue 1 (2nd January 2022)

• Record Type: Journal Article
• Authors: des Roseaux, Marion Delacoux; Shi, Shengjing; Duff, Aoife M.; Brennan, Fiona P.; Condron, Leo; Finn, John A.; Richards, Karl G.; O'Callaghan, Maureen; Clough, Tim J.
• Is Part Of: New Zealand journal of agricultural research. Volume 65:Issue 1(2022)
• Page Start: 42
• Page End: 62
• Publication Date: 2022-01-02
• Subjects: Biological nitrification inhibition -- mitigation -- nitrification -- nitrous oxide -- nosZI -- pasture -- Plantago lanceolata; Agriculture -- Periodicals; Agriculture -- New Zealand -- Periodicals; Animal culture -- Periodicals; Animal culture -- New Zealand -- Periodicals; 630.99305
• DOI: 10.1080/00288233.2020.1848880
• Languages: English
• ISSNs: 0028-8233

Abstract

ABSTRACT: Multispecies grasslands can alter nitrogen (N) cycling processes. A mesocosm experiment was performed comparing bare soil, soil planted with perennial ryegrass (Lolium perenne), white clover ( Trifolium repens ), plantain ( Plantago lanceolata), and a mixed sward with all three species. We aimed to assess the plant effects on: ruminant urine-induced dry matter yields, plant N uptake, soil N2 O emissions, and genes encoding nitrifier and denitrifier N transformations. After 35 days urine application increased both dry matter in the plantain (11%) and mixed (19%) swards, and N uptake in the ryegrass (63%), plantain (120%) and mixed (103%) swards. Urine increased cumulative N2 O emissions, and while there was a trend for greater N uptake to cause lower emissions this was not significant. Urine addition elevated inorganic-N concentrations with few differences between plant treatments. Ammonia oxidising bacteria increased under urine but plantain did not inhibit this response. On days 3–10, increases in nirK and nosZI were indicative of enhanced nitrifier-denitrification and N2 O scavenging by denitrifiers, respectively. The elevation of nosZI under urine-affected soil warrants further investigation in relation to potential pasture species effects. Consistent with previous in situ studies this study showed no evidence of plantain affecting soil inorganic-N concentrations via biological nitrification inhibition.