Nitrogen (N) fertilizers are the backbone of agricultural production and modern food systems. An artifact of World War II, N fertilizers in the form of ammonium and nitrate are combined with other materials to supplement plant nutrition. My PhD project at the University of California, Davis, concerns N use efficiency, which is loosely defined as the amount of N making its way into the plant versus N lost to the environment.
Nitrogen use efficiency research is essential in order to address a number of agro-environmental challenges such as water quality and climate change. Simply put, there are two main forms N is lost from agricultural systems; liquid and gas. Nitrates in water leach through the soil profile, into groundwater. and eventually to the ocean. My research focus is on the gaseous component.
On an irrigated almond orchard in Lost Hills, California (far from Cable Cars and Hollywood Stars) we sample gas flux from soil throughout the year in an attempt to quantify nitrous oxide (N2O) emissions. Why? The main driver is N2O has 300 times the global warming potential than a molecule of carbon dioxide (CO2). In other words, it hangs out in the atmosphere longer and absorbs more radiation compared to CO2. Ultimately, we need to consider how the plant food we use to grow our food impacts the atmosphere and climate change.
The goal of agricultural researchers is to identify N management strategies for almond growers to sustain yields of these protein-rich nuts while helping to reduce greenhouse gas emissions. Is it novel, sexy, or just plan pragmatic? I am curious to know your opinion about how you view agriculture’s role in broader societal challenges.
How (un)realistic is the implementation of a massive composting project/movement?
Are these accurate statements?
“The main driver is N2O has 300 times the global warming potential than a molecule of carbon dioxide (CO2). In other words, it hangs out in the atmosphere 300 times longer than CO2.”
Is it because it remains 300 times longer, or because it has different properties (absorption, emissivity, etc.)?
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Andrew, you’re right my statement is not completely accurate. Nitrous oxide gas remains longer in the atmosphere and has a higher radiative absorption compared to CO2. I’ll edit my statement to reflect your comment. Thank you.
Paramliv Kaur, that is a great question. There are opportunities and challenges with any project. Such a movement would probably be decentralized, in proximity to populated areas, and under less intensive agricultural production.