Achieving low-carbon agriculture with nitrogen management
Managing the soil is a big part of farming. In recent years there’s been a rapid shift to low-carbon agriculture. This is an opportunity for farmers to focus on practices and innovations that help soils become more sustainable for farmers and the environment, particularly in storing carbon to manage rising greenhouse gas emissions worldwide.
Low carbon farming is an approach that reframes how crops are cultivated in such a way that benefits soil health and its properties. And while the conversation usually revolves around carbon, another key component in regenerative agriculture is managing nitrogen.
Nitrogen added through chemical fertilizers has received negative attention due to the wide scale pollution it causes when used excessively. However, with the rise of low-carbon agriculture, it’s worth understanding what role nitrogen plays in soil carbon sequestration.
- What is carbon farming?
- The problem with nitrogen
- Why is nitrogen important in growing crops?
- Nitrogen management for low carbon agriculture
- Getting started
Nitrogen in carbon farming?
It’s becoming more apparent that for agriculture to solve the triple problem of growing demand for food, increasing the resilience of food production, and climate change-related complications, changes must happen in the industry. Shifting to low-carbon agriculture is one solution to the industry’s problems, more commonly referred to as carbon farming.
Carbon farming combines the soil-building practices of regenerative agriculture with added financial incentives for farmers. Just like in regenerative agriculture, adopting practices that focus on soil health such as cover crops, conservation tillage, crop rotation, and residue management, to name a few, all help to keep carbon stored in agricultural soils. Farmers receive revenue when their fields are verified carbon sinks through carbon credits sold to buyers.
When soils are rich in carbon, it helps plants thrive with improved soil properties. Of course, plants don’t just need carbon, but a whole host of other macro- and micro-nutrients which include nitrogen. Dealing with nitrogen has traditionally been tricky because both limited and excessive application of N can become problematic considering how closely related the nitrogen cycle is to the carbon cycle, as well as the way it affects soil and plant nutrient cycling.
Issues caused by over-nitrification
Farmers know how important nitrogen is to growing crops. At the same time, it is also usually limited in most soils. This is why adding nitrogen, either in synthetic form or organic sources, is a necessary farming practice for most.
Managing arable land by adding nutrients has inadvertently caused soil degradation and environmental pollution. Not particularly because of nitrogen itself, but the excessive amounts it has been added into the soil for higher yields.
High levels of synthetic fertilizer have been the secret to high-yielding, intensive farms. Nitrogen-containing fertilizers like urea or compound NPK fertilizers with the unoptimized application have been found to get washed away to nearby water sources. Apart from nitrogen runoff in water, nitrogen is also a problem for the atmosphere. In the EU, it is reported that 92% of ammonia (a form of nitrogen found in fertilizers) accounts from the agriculture sector.
Nitrogen (in the form of nitrous oxide (N2O), ammonia, and nitric oxide) is one of the most potent greenhouse gasses that trap heat in the atmosphere that causes climate change. 1 kg of N2O is about the same as 298 kg of carbon dioxide and lasts longer in the atmosphere.
And while abundant chemical fertilizers have been known culprits of nitrogen leakage, organic sources of nitrogen such as manure are unmanageable and can also cause the same problems as synthetic ones if left unchecked.
Modern agriculture wouldn’t be possible without nitrogen
Despite known problems caused by over-nitrification, fact remains that nitrogen management is an indispensable part of growing crops. It’s just a matter of better management and techniques to make sure that leakages in soil, water, and air are avoided.
Nitrogen plays a key role in nutrient uptake between soils and plants. In agriculture, this means that sufficient nitrogen inputs can affect crop growth and yield. Because of this, the presence of nitrogen that plants can use to sustain their growth can determine the yield, and therefore the profitability of farms. Nitrogen really is an important component of farm productivity.
However, the method, timings, doses, and types of fertilizer application can be improved for most farms. While nitrogen in soil boost productivity, both plants and soils can only take and process so much of it. It has been found that most fertilizer application gets wasted due to overfertilization. And over time, long-term use of synthetic inputs can be harmful to the soil and the microbial life that helps transform nutrients useful for plant growth.
While the importance of nitrogen in plant growth is often emphasized, nitrogen is also a key element for soil health, especially in the processes needed for soil carbon storage.
Nitrogen management is crucial for low-carbon agriculture
Striving for low-carbon agriculture is provisioned by carbon farming. In carbon farming soil is managed by utilizing practices that increase the carbon content of the soil, granting profits to farmers for doing so. These practices generally lie between these 2 categories, where nitrogen management plays important roles:
- Emissions reduction
- Soil carbon sequestration
Managing nitrogen to limit farm emissions
Optimized use of organic or synthetic fertilizers can have a great impact on farm emissions. One way to do this is to keep track of applications and doses with farm management software. Precision technology in agriculture is also on the rise because it makes farm tasks such as nutrient application more efficient.
By only using what’s needed in the field, not only are emissions lowered, but it can also mean decreased costs for farmers, especially at a time when fertilizer prices are skyrocketing.
Storing carbon in the soil with nitrogen
While regenerative farm practices put carbon as a central element in both soil health and climate change mitigation, this objective will not be possible if not for nitrogen.
Without enough nitrogen, CO2 cannot be effectively processed by plants and soil microbes into a stable form of carbon in the soil. This puts carbon farming at risk of failure. Carbon farming practices such as using cover crops can improve nitrogen fertilization of the soil especially when leguminous plants are introduced, which are known to make better use of nitrogen.
Making low-carbon agriculture work for farmers
Managing nitrogen fertilization is quickly becoming an important part of sustainable farming. As farmers shift to carbon farming, it’s worth knowing which practices can help optimize fertilizer use and how to do it properly.
Start with a carbon program that guides farmers to achieve carbon credits that generate income. After initial farm assessments, receive expert farming recommendations from agronomists. Learn which historical practices are impacting the farm that can be improved to generate high-quality carbon credits that help with soil health and emission reductions.
Get in touch with us about carbon farming today!
- Almaraz, Maya & Wong, Michelle & Geoghegan, Emily & Houlton, Benjamin. (2021). A review of carbon farming impacts on nitrogen cycling, retention, and loss. Annals of the New York Academy of Sciences. 1505. https://doi.org/10.1111/nyas.14690
- Pan, SY., He, KH., Lin, KT. et al. Addressing nitrogenous gases from croplands toward low-emission agriculture. npj Clim Atmos Sci 5, 43 (2022). https://doi.org/10.1038/s41612-022-00265-3
- Sainju, U. M., Ghimire, R., & Pradhan, G. P. (2019). Nitrogen Fertilization I: Impact on Crop, Soil, and Environment. In E. C. Rigobelo, & A. P. Serra (Eds.), Nitrogen Fixation. IntechOpen. https://doi.org/10.5772/intechopen.86028
- EEA. European Union emission inventory report 1990‑2017. 148 (European Environment Agency, Copenhagen, 2019).