Nitrous oxide (N2O) is one of the most harmful GHG’s, and agriculture is one of the main sources of N2O emissions. The amount of N2O produced from the soil through the combined process of nitrification and denitrification is profoundly influenced by temperature, moisture, carbon, nitrogen, and oxygen contents. This document will focus on how the implementation of VitaSoil, and its effect on soil and animal health, can help reduce GHG’s, particularly focussing on emissions of nitrous oxide and ammonia (NH4+).
VitaSoil is a highly concentrated blend of carbon and beneficial microbes. All components are individually produced and incorporated to enhance the efficacy of each component. Our carbon components include labile carbon (microbially digestible) and stable carbon (biochar). These carbon components are inoculated with soil beneficial microbes derived from manure-based earthworm castings (Psuedomonas, Rhizobium, Azerbacter, Bacillus, Azosprillium) and a product containing Bacillus sp (b. ameloliquifaciens, b. laterosporus, b. lichiniformus).
In soils, N2O is mainly produced by the transformation of reactive N through specific microbes. Three main processes (1) nitrification (2) denitrification and (3) dissimilatory nitrate reductions, are considered the main contributors to N2O emissions. Microbes play a central role in the processes of both the production and reduction of N2O. Nitrification is the two-step oxidation of ammonia (NH3) to nitrate (NO3-) via nitrite (NO2-). Denitrification is the process of reducing NO3- to dinitrogen (N2) which leads to the production of N2O. All of these processes are carried out by soil microorganisms, namely ammonia-oxidizing archae (AOA) and ammonia-oxidizing bacteria (AOB) [1]. It is also well accepted that denitrification and the reduction of nitrite to ammonium are the main pathways contributing to the production of N2O and that pH can also have a substantial influence on the denitrifying process. Several experiments have shown that denitrification at low soil pH produces more N2O and increases the ratio of N2O to N2, thus indicating that N2O is the dominant product in acidic soils (Cuhel et al., 2010).
The major factors affecting N2O emissions from agricultural soils are:
Each kg of VitaSoil contains 1,5 x 1010 bacillus sp. Of which 30% is bacillus ameloliquifacien (BA). A study carried out by the Key Laboratory of Environmental Biotechnology, Research for Eco-environmental Sciences, Chinese Academy of Sciences 2019, showed that the addition of BA reduced N2O emissions by a net 50% compared to control. This was due to the effect that BA has on enhancing the activity of functional bacteria that, in turn, reduce ammonia-oxidizing bacteria that produce N2O. In addition, BA added to the soil promoted plant growth, enhanced the soil pH, and increased the total nitrogen contents in plants.
The results also showed that b. ameloliquifaciens raised the pH of acidic soils, which, correspondingly, shaped functional communities within the nitrogen cycle. These changes in chemical properties of soil impacted the activities of microbes involved in N cycling and led to the mitigation of N2O emissions. Many studies have shown that during the nitrification process, the conversion of NO2- to NO3- is limited in acidic soils because of the relatively low activities of nitrite-oxidizing bacteria, which enhances the possibility of NO2- being reduced to N2O. Nevertheless, an increase in soil pH facilitates the immediate conversion of NO2- to NO3- thus limiting the availability of NO2- for its reduction to N2O.
Biochar is a stable, carbon-rich product from the thermal treatment of biomass at high temperatures in the absence of oxygen. This treatment significantly alters the biomass physical and chemical properties, thereby, creating biochar with a porous structure, high surface area, and added functional groups on the surface. As a result of these changes, biochar possesses unique physical and chemical properties that can help capture pollutants (solid, liquid, or gaseous) that would otherwise be released into the environment by serving as an adsorbent. Utilizing biochar in animal production has the potential to adsorb pollutants, improve the welfare and productivity of animal growth, increase soil carbon sequestration, and increase the value of manure-based fertilizer.[2]
Biochar application hinders GHG emissions by sequestering carbon, improving soil properties involving physical, chemical and biochemical changes, influencing N2O production.[3] The application of biochar could reduce the emissions of N2O and NH3 by 16.10% and 89.60% respectively. [4] The application of biochar increases soil pH and drives N2O complete reduction to N2, thus curbing N2O emissions. The main effects of biochar – modification of soil pH (which restores N2OR functioning responsible for transforming N2O to N2), aeration (which increases O2 and creates adverse conditions for denitrifying bacteria) and water holding capacity – are those responsible for reducing N2O emissions. However, biochar also directly absorbs N2O, which further contributes to reduced emissions.
Additionally, biochar has good adsorption potential, resulting in considerable adsorption on its surface of NH4+ and NO3-, which reduces the N availability for N2O production.
Chemical fertilizers account for a large proportion of N2O emissions into our atmosphere. Reducing the need for these inputs, by improving soil fertility, will reduce these GHG emissions. VitaSoil increases soil organic matter by recolonizing beneficial microbial populations, neutralizing pH and stimulated the production of humus. Numerous long-term studies have shown that restoring soil organic matter and humus results in more efficient nutrient storage and uptake with less water. This translates into less N2O emissions, fewer nitrates in the water sheds, and more carbon stored in the soil. VitaSoil accelerates the production of humates (through naturally occurring humic acid) which results in improved physical structure of soil. This facilitates easier tillage, increased soil water holding capacity, reduced erosion, better formation and harvesting of root crops, and deeper, more prolific plant root systems, as well as improvements in nutrient cycling. Improved soil structure also reduces waterlogging in soil, responsible for excess emission of N2O.
VitaSoil is used to improve quality of feed, and improve the quality of bedding in the poultry industry. As mentioned above, VitaSoil enhances soil health by establishing an environment for microbes to colonize as well as feeding those soil-benevolent microbes directly to soils, which in turn, improves plant and animal health. VitaSoil contains phosphate-solubilizing bacteria, which improve phosphorous uptake by plants, a crucial function responsible for sugar movement within plants, translating in higher brix levels in plants. In addition to P solubilization, humic substances (produced by microbes in VitaSoil) partner up with magnesium and speeds up plants metabolic processes, ensuring enough Mg is available for photosynthesis. Mg, coupled with humic substances, liberates CO2from soil calcium carbonates thus making CO2 available to the plant through the roots. The humic substances also stimulate plant enzymes which further aids the production of sugars in the plant leaf. Brix is a scale that measures the sugar content of plants based on a light refraction index. Plants with high brix levels (>10) are more nutritious and more resistant to pests through the natural production of plant resistors, such as jazmonic acid. With increased nutritional content in plants, animals are now getting more in each bite. In essence, a cow that normally takes three mouthfuls, will now need only two to receive the same nutritional content whilst grazing.
Biochar is also set to garner huge momentum in the animal feed industry. By applying VitaSoil to pastures, inevitably, livestock will ingest surface applied biochar, a major component of VitaSoil. This also applies to the poultry sector as biochar amended beds have shown to have significant benefits to bird health. Recent studies have uncovered huge benefits of char with regard to animal health, namely: [5]
In addition to these benefits, studies have noted the following other effects of using biochar in animal feed: [7]
For the purpose of reducing GHG emissions, long lasting organic amendments that restore soil biology are preferred because they slow down the decomposition and enable organic matter to persist and build up in soils. VitaSoil can amend the soil C:N ratio and soil microbial communities, improving a soil’s fertility, porosity, nutrient and water holding capacity, cation exchange capacity, and long-term storage of stable, bio-available forms of carbon and nitrogen. These benefits help to reduce N2O emissions through suppressing the conditions for ammonia-oxidizing bacteria and archaea to survive. VitaSoil also helps regulate soil temperature and moisture that affect N2O emissions.
[1] Wu, Bai, Zhuang, Han – Article in Global Change Biology Dec 2017. www.researchgate.net/publication/321889997
[2] Graves, Kolar, Shah, Grimes, Sharara Appl. Sci. 2022, 12, 5042. https://doi.org/10.3390/app12105042 Can Biochar improve the sustainability of animal production? www.mdpi.com/journal/applisci
[3] Case, McNamara, Reay, Whitaker. The effect of biochar addition on N2O and CO2 emissions from a sandy loam soil. 2012, 51, 125-134
[4] He, Xu, Li, Xhang, Liu, Lyu, Wang, Tang, Wang, Zhao. Biochar mitigated more N-related global warming potential. Sci. Total Environ 2022, 821, 153344
[5] https://feeco.com/biochar-applications-in-animal-husbandry/
[6] Leng R A, Preston T R and Inthapanya S 2012: Biochar reduces enteric methane and improves growth and feed conversion in local “Yellow” cattle fed cassava root chips and fresh cassava foliage. Livestock Research for Rural Development. Volume 24, Article #199. Retrieved May 24, 2017, from http://www.lrrd.org/lrrd24/11/leng24199.htm
[7] Gerlach A, Schmidt HP: The use of biochar in cattle farming, the Biochar Journal 2014, Arbaz, Switzerland. ISSN 2297-1114 www.biochar-journal.org/en/ct/9 Version of 01 th August 2014.