 Did you know that scientists have been digging up dirt on soil for centuries? From Vasily Dokutayev, the father of soil science in the 19th century, to Hans Yenny in the 20th, and numerous mines at the frontier of soil science in the 21st century and today, researchers have been studying how soils form and build up organic matter. Most recently, they've been building big data models that predict how soil carbon and essential component of soil organic matter will respond to Earth's rising temperatures. With the introduction of large-scale data collection programs like the National Ecological Observatory Network, scientists are now better prepared to answer long-term questions about soil health, the fate of soil organic carbon, and CO2 exchange between the atmosphere and soil. Soil is made up of air, water, minerals, organisms, and organic materials. Within soil, most concentrated near the surface lies soil organic matter, or SOME, which consists of plant, animal, and microbial tissues in various stages of decomposition. Living organisms like worms, bacteria, and fungi are key to turning this dead matter into stable SOME. SOME plays a key role in many soil functions. It promotes infiltration and increases water holding capacity and soil fertility and reduces erosion. Although SOME only makes up less than 15% of the mass of many soils, at the global scale it contributes a huge volume of carbon. When added up across all terrestrial ecosystems on Earth, soils are currently storing an estimated 2,500 billion tons of carbon, almost twice the amount that is found in our atmosphere. Roughly 50% of SOME is actually carbon, that if decomposed will create carbon dioxide. Along with carbon, nitrogen, phosphorus, and sulfur are also stored in soil organic matter, and are eventually released to be made available for plants to take up when SOME is decomposed. In a healthy, undisturbed, or mature ecosystem, there is a general balance of CO2 uptake by plants, and the CO2 created in soils from decomposition. This is called a steady state. However, the degradation of many ecosystems through climate change, land usage, agricultural practices, and other human activity and disturbance has led to the decreased ability of soils to store carbon, compared to the increasing CO2 that is released by our ecosystems. In this case, the steady state is unbalanced. Why are healthy soils good at storing carbon, and how does it get locked away in soil organic matter? There are several ways carbon can be protected from decay. It may be prevented from decomposing in wet and cold environments, or interactions with soil minerals. It can be stored away inside soil aggregates, or it might remain because the organisms that typically break down SOME might be absent. With new, advanced measurement techniques, we are able to get an exciting look into carbon cycling and storage in soils. Open data and samples from the National Ecological Observatory Network can contribute to this understanding. N-C2 measurements can observe carbon cycling in place. For instance, eddy covariant systems continuously measure CO2 exchanged between soils, plants, and the atmosphere, while below-ground sensors constantly measure the amount of carbon dioxide in the spaces between soil particles. In addition to these instrument measurements, we can make high-resolution molecular measurements of the composition of SOME and the organisms that break it down. NEON collects soil samples throughout the U.S. at regular intervals for scientific research. These samples are collected, processed, and shipped to the main NEON biorepository in Arizona for storage, where they can be freely requested by researchers. Methods such as radiocarbon dating can help us understand how long different kinds of organic material persist in soils, and advanced spectroscopy techniques reveal the exact chemistry of soil-organic carbon, which helps us understand how it forms. Combining these measurements with microbial community analyses can give insight into how soil organism shapes SOME dynamics. Scientists learn more every day about the fine-scale dynamics of carbon cycling within soil-organic matter, and how stored carbon can have broad implications on overall soil health and the carbon cycle. Measuring these carbon stores and exchanges is critical in providing data that better-informed scientific models develop to predict future soil-carbon concentrations. It's important that we, as a society, better understand why and how carbon concentrations in soils are changing, so that we might learn how to mitigate rising CO2 levels in our atmosphere that contribute to climate change. Can you dig it? To learn more, visit neonscience.org