Signals in the Soil
In 1935, President Franklin D. Roosevelt stated, “A nation that destroys its soils destroys itself." This statement remains true to this day. Soils form over hundreds of years, and yet can be destroyed in a single event. They are an often-overlooked natural asset despite being the foundation of terrestrial ecosystems that support food production, economic prosperity, and many other services that are essential for humanity. Soils are complex ecosystems composed of organic matter, minerals, water, air, and billions of organisms. Such ecosystems interact with the flora and fauna they support to mediate myriad biological, chemical, and physical processes essential for plant growth, food and fiber production, and contaminant removal. Soils are also the foundation material for all structures not supported on rock, and, by orders of magnitude, are the most widely-used construction material in the world. Soils are the source of most of the antibiotics used to fight human diseases, control the movement of water and chemical substances between the Earth and atmosphere, and act as source and storage media for gases such as oxygen, carbon dioxide, and methane.  As a result of their essential importance, soils are also part of our cultural heritage. Furthermore, soils serve as major storage media for carbon, a role that is potentially exploitable in climate change mitigation and adaption strategies. Thus, as the Earth’s population grows, we need a better understanding of soil ecosystems that will continue to play a critical role in supporting societies around the world. The National Science Foundation (NSF) Directorates for Engineering (ENG) and Geosciences (GEO), the Divisions of Integrative Organismal Systems (IOS) and  Environmental Biology (DEB), in the Directorate for Biological Sciences (BIO), the Division of Computer and Network Systems (CNS) in the Directorate Computer and Information Science and Engineering (CISE), the Division of Chemistry (CHE) in the Directorate for Mathematical and Physical Sciences (MPS), the Division of Behavioral and Cognitive Sciences (BCS) in the Directorate for Social, Behavioral, and Economic Sciences (SBE), in collaboration with the US Department of Agriculture National Institute of Food and Agriculture (USDA NIFA) encourage convergent research that transforms existing capabilities in understanding dynamic soil processes, including soil formation, through advances in sensor systems and modeling.  The Signals in the Soil (SitS) program fosters collaboration among the two partner agencies and the researchers they support by combining resources and funding for the most innovative and high-impact projects that address their respective missions. To make transformative advances in our understanding of soils, multiple disciplines must converge to produce environmentally-benign novel sensing systems with multiple modalities that can adapt to different environments and collect and transmit data for a wide range of biological, chemical, and physical parameters. Effective integration of sensor data will be key for achieving a better understanding of signaling interactions among plants, animals, microbes, the soil matrix, and aqueous and gaseous components. New sensor networks have the potential to inform models in novel ways, to radically change how data is obtained from various natural and managed (both urban and rural) ecosystems, and to better inform the communities that directly rely on soils for sustenance and livelihood.