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Helping Farmers Reduce GHGs

Agrisilica® - Reducing N2O and CH4

As the world focuses on greenhouse gas emission sources, agriculture is coming under intense scrutiny.

Surprisingly, most of agriculture’s emissions come from Nitrous Oxide (N2O). High nitrogen (N) fertiliser inputs, together with low N fertiliser use-efficiency, results in significant fertiliser losses via N2O emissions and leaching. Crops recognised as the highest contributors to N2O emissions are rice and sugarcane. Agrisilica® can reduce N2O emissions by up to 40%. Methane (CH4) emissions in irrigated cropping can be significant. Agrisilica® can reduce CH4 emissions.

N2O - productivity at a cost

  1. Food production is likely responsible for 80% of increased atmospheric levels of N2O, due to the addition of synthetic nitrogen fertilizers.
  2. N2O is around 300 times more potent than CO2, with a lifespan of between 118-131 years before it disintegrates.
  3. Annually, more than 100 million tonnes of nitrogen is spread on crops in the form of synthetic fertilizers, which were introduced in the early 20th century.
  4. Reactive nitrogen losses into the environment (atmosphere, water sources and oceans) is considered the most widespread and intractable environmental problem facing major crop-producing regions around the world.
  5. It has been estimated nitrogen losses (nitrogen not absorbed by crops) can cost farmers up to 25% of the annual profit.

Monosilicic acid, known as PAS, is naturally derived and 100% bioavailable to plants. Agrisilica® is PAS-rich.

“…we conclude that application of monosilicic acid to the soil can reduce greenhouse gas emissions and reduce the impact of global climate change on agricultural activity”.*
*Włodarczyk T, Balakhnina T, Matichenkov V, Brzezińska M, Nosalewicz M, Szarlip P, Fomina I. Effect of silicon on barley growth and N2O emission under flooding. Sci Total Environ. 2019 Oct 1;685:1-9. doi: 10.1016/j.scitotenv. 2019.05.410. Epub 2019 May 29. PMID: 31170590.

Examples of how Agrisilica® reduces N2O emissions


  • Physiologically promotes ammonium assimilation and restrains the increase in water soluble nitrogen compounds.
  • Improves the fixation in plants of nitrogen (N2) by rhizobia (bacteria that fix nitrogen).


  • Alters denitrification process and reduces intensity of oxidative damage, and …
  • Improves availability and efficiency of silicon as nutrient …
  • All resulting in reductions of N2O emissions, run-off and leaching.


  • Increases chlorophyll content and photosynthetic capacity, reduces the transpiration rate and increases nutrient uptake.
  • Associated with lignin–carbohydrate complexes in the cell wall of epidermal cells of sugarcane.
  • Suppresses the activity of certain enzymes particularly invertase, resulting in greater sucrose production.
  • Increases phosphate and potassium uptake by 40-70% and 20% respectively, all of which combine to … reduce N2O losses by as much as 40%.

20 Years of rice production’s Global Warming Potential (GWP) could equal 1,200 coal plant emissions*

Methane (CH4) is another greenhouse gas associated with agriculture. Of all crops, rice is the largest producer of CH4. Rice accounts for around one-fifth of the world’s supply of calories, and is the staple crop to over 5 billion people.

*Environmental Defence Fund, NY 2019.

CH4 - reducing it is critical to lowering global warming

  1. Methane (CH4) has over 80x the warming power of CO2 during its first 20 years in the atmosphere. It then tapers to around 25x potency.
  2. Rice cropping using irrigation methods is the largest contributor to CH4 emissions.
  3. Rice paddies emit between 33 to 40 Tg(CH4) yr–1 and 90% of these emissions come from tropical Asia. (Yan et al., 2009).

Modes of Action by which Agrisilica®
may reduce CH4 emissions

Crops grown with Agrisilica® generally require less water and therefore may result in reduced CH4 emissions:
Methane is produced mainly in crops grown in standing water i.e. primarily rice, where the water lacks oxygen (anoxic, leading to anaerobic conditions). This is ideal for the growth of methane-producing bacteria living in the soil. Methane-producing bacteria (methanogens) convert soil carbon into methane which is released into the atmosphere. Farming rice using intermittent watering systems or farming dryland rices reduce the incidence of anaerobic conditions and the growth of methanogens will produce less CH4 emissions.
Trials using Agrisilica® record improved rice yields and Harvest Index:
Research has indicated that by improving rice yields, and specifically the Harvest Index (mass ratio of grain yield and total above-ground dry matter), reduced overall CH4 emissions.
Trials using Agrisilica® record improved performance under high UV-B conditions:
Increasing ultraviolet-B (UV-B) radiation resulting from depletion of the ozone layer can have damaging effects on crops and result in higher CH4 emissions. Research indicated silicon reduces CH4 production in rice grown in high UV-B conditions.

We welcome your further interest in Agrisilica®

Please get in touch by email or phone Agripower on +61 2 9251 8884