News & Insights

Climate change is one of the most serious threats to the world as we know it. Agriculture is responsible for 10% of greenhouse gas (GHG) emissions in the United States, and about half of those emissions can be attributed to soil management (1). Since Fritz Haber discovered how to turn nitrogen gas into fertilizer over 100 years ago, crop yield has skyrocketed (2). While this is good news for growing global food demand, overapplication of fertilizers also leads to leaching of nutrients into waterways, causing environmental damage in places like the Chesapeake Bay and the Gulf of Mexico. Additionally, the production and use of nitrogen fertilizers is responsible for the majority of GHG production in the soil. 

With these factors in mind, growers have been working to implement more sustainable soil management practices and reduce GHG emissions. In order to develop, execute, and evaluate these practices, the soil should be considered more holistically than chemical measurements like pH and nutrients. A major, often forgotten component of soil health is the vast number of organisms that make it a thriving, living ecosystem. How vast? In 1 teaspoon of soil, there can easily be 1 billion microorganisms (3). Combined together, all the living organisms in the top six inches of a healthy soil over one acre can weigh more than 5,000 pounds (4). Understanding the diversity of species present can help us to both evaluate soil health and formulate a plan to improve it. 

Many soil species are microorganisms (aka microbes) and invisible to the naked eye, so how can we know what different microbes are there? Here’s where DNA comes in. Historically, microbiologists have studied these tiny beings using microscopes or by growing them as cultures in a lab. Advances in DNA sequencing technology in recent decades have led to the development of metagenomics—sequencing all the DNA in an environment. Metagenomic analysis of soils has shone a light on the true level of biodiversity that has, until now, gone undiscovered (5). Trace Genomics has developed a groundbreaking platform for analyzing metagenomic data and translating it into tangible actions. Looking at DNA can give us both identifying information (is a pathogen present?) and functional information (can anyone here make nitrates?), all of which can be used to measure soil health.

This brings us back around to climate change. With advanced technology to study soil microbes, we can better understand how they’re impacting GHG emissions. The largest and most direct way that microbes contribute to GHG levels is the production of nitrous oxide (N₂O), a much more potent greenhouse gas than CO₂ (6). High N₂O production is more likely to occur on heavily fertilized soils (7) and those with poor drainage (8). Not all microbes produce N₂O, so understanding this process isn’t as simple as measuring the amount of microbes in the soil. Trace can detect the genes responsible for N₂O production in our metagenomic data, and provide growers with a benchmarked quantity of how many of these microbes are in their field.