Niu - Collaborative Research: SitS NSF UKRI: Decoding Nitrogen Dynamics in Soil through Novel Integrated in-situ Wireless Soil Sensors with Field Modeling

Excess nitrogen leaching from agricultural and horticultural lands into waterways is a long-standing challenge for agricultural sustainability and environmental protection. An effective approach to improving the water/fertilizer use efficiency is through precision farming practices guided by real-time monitoring and near-term forecast of crop irrigation and fertilization needs. However, this initiative is hampered by the lack of reliable sensing technologies and modeling tools for elucidating the spatiotemporal variability of soil moisture and nitrogen concentration. The current state of the art is to collect soil samples at field sites and bring to the laboratory for analysis, which is prohibitively expensive, labor-intensive, and is unable to track the transient variation of soil nitrogen content in a timely manner. This interdisciplinary collaborative US-UK SitS project aims to tackle the grand challenge of decoding nitrogen dynamics in the soil through seamless integration of four innovative solutions: hydrogel-coating solid-state ion-selective membrane (HS-ISM) based wireless nitrogen sensing technology, droplet-flow microfluidic-based sensors (DFMS) as in situ calibration, high-resolution profiling of nitrogen species and moisture level in different ecosystems, and data-driven modeling of rhizosphere nitrogen dynamics. Together, this project will transform existing labor-intensive and inefficient soil analysis practice to automated and highly efficient soil nitrogen dynamics decoding and field modeling strategy, and thus advancing the underlying science and engineering of soil nitrogen dynamics and providing guidance for sustainable agricultural and ecosystem management.