You are here

denitrification

Catalogue: GRDC Updates
Field trials on northwest NSW cracking clay soils (Vertosols) during 2011-2013 showed that surface application of urea led to ammonia volatilisation averaging 11% N loss when applied to fallow soils, and 5% N loss when applied to tillering wheat crops... Compared to urea, losses from ammonium sulfate were less, except when the soil contained >2% calcium carbonate (lime)... At the conclusion of the month, we sampled soils and plants (at in-crop and pasture sites) and measured soil nitrate and ammonium and plant total N. We did not measure N uptake into grain...
Related categories:
Catalogue: GRDC Media
Saturating winter rain across parts of southern and central NSW have left some crops waterlogged and growers questioning how to approach nitrogen (N) management over the coming weeks... The challenge facing growers is to determine whether N should be applied to water-affected crops and if so, how much and when... Incitec Pivot Limited (IPL) technical agronomist Jim Laycock said N applications should only be considered in paddocks where water is laying when that water is receding and soil has begun to dry out...
Related categories:
Catalogue: GRDC Research Summaries
There is a need to improve N management in Australia's grain production systems, both for economic and environmental reasons... This project aims to develop a compendium (knowledge document) plus interactive excel-based decision support (DS) software ('NBudget') for improving knowledge and management of soil, fertiliser and legume N. The N management package is targeted at farmers and advisers... We also propose to promote the use of the N management package through workshops and GRDC Updates...
Related categories:
Catalogue: GRDC Media
The onset of summer rains will see denitrification back on the management agenda of northern region grain growers looking to maximise crop performance and grain quality... Wet summers increase the potential to lose nitrogen through denitrification as it occurs when soils are nearing saturation and oxygen becomes limited... In a bid to help northern growers manage denitrification and preserve profitability once wetter cropping seasons return, the Grains Research and Development Corporation (GRDC) has released a new Denitrification Fact Sheet...
Related categories:
Catalogue: Ground Cover
Trials have shown significant denitrification in summer after post-harvest mineralisation of crop residues such as chickpea crops and canola... In 'normal' dry years, losing soil nitrate through denitrification is a relatively small problem - a bigger issue now is the slowly declining soil nitrogen reserves across the region, especially after multiple above-average yields... Wet summers increase the potential to lose nitrogen through the natural process of denitrification, so the potential for losses is higher under those conditions...
Related categories:
Catalogue: GRDC Media
Water logged soils can result in significant N loss through denitrification... Professor Grace says the first step in defining a nitrogen program is for growers to observe how their soils respond to rainfall to better understand how they are likely to lose nitrogen (see breakout box on types of N loss)... Previous work has shown that for every 1 kg of N lost as N 2 O, as much as 10-50 kg of N may be lost to N 2 ...
Related categories:
Catalogue: GRDC Media
Water logged soils can result in significant N loss through denitrification... Professor Grace says the first step in defining a nitrogen program is for growers to observe how their soils respond to rainfall to better understand how they are likely to lose nitrogen (see breakout box on types of N loss)... Previous work has shown that for every 1 kg of N lost as N 2 O, as much as 10-50 kg of N may be lost to N 2 ...
Related categories:
Catalogue: GRDC Updates
Specific management practices alter the abundance and activity of microbes capable of processing both organic and mineral-N... Once we better understand the soil biological and chemical factors governing N-transformations in our agricultural systems, we can determine how agronomic practices can be used to synchronise N supply, from both fertiliser and soil sources, with crop demand... A primary goal of this project was to develop and use molecular tools to detect these N-cycling communities in Australian agricultural systems...
Related categories: