Population growth, aggressive farming practices, and climate change have put significant stress on the food production system for sustainable growth. Agricultural runoff from over-fertilization and waste from large farms into natural water sources can cause algae outbreaks, reduce the dissolved oxygen in water, resulting in ecosystem disturbance and decline in fish populations. Precision agriculture with data-backed decision-making such as fine-grained spatiotemporal soil properties (moisture, temperature, pH, nutrients, organic matter, etc.) has potential to improve the efficiency of the farming practices by increasing crop growth and reducing agricultural runoff that contaminates surface and groundwater along with other negative environmental impacts. Current practice of soil property measurement relies heavily on taking samples for laboratory testing, which is costly and time consuming for implementation over large areas. This project will investigate a low-cost autonomous soil nutrient sensing system to support precision agriculture by integrating microelectromechanical system sensors, ground penetrating radar, as well as autonomous unmanned aerial vehicle-enabled wireless sensor network.
The project includes the development of a passive, low cost, pervasive, maintenance-free sensor that can be interrogated wirelessly and provide measurement of soil water content, temperature, pH, and nutrient concentration. The project focuses on detecting and evaluating nitrate and heavy metal ions concentration in the soil, which are indicators of agricultural runoffs and environmental contaminants. For this purpose, surface acoustic wave sensors that consist of surface acoustic wave delay lines and conductive polymer-based impedance sensors connected to a reflector will be considered as the main sensing modules. The sensors can be placed in the soil for in-situ measurement. The specific research objectives of this project are to: 1) identify specific polymers for nitrate and heavy metal ion detection, 2) design, fabricate and validate the surface acoustic wave sensors, 3) design and select proper antenna and ground penetrating radar for wireless measurement of the passive sensors, and 4) integrate the data analysis and communication system. The project team has a collective research expertise in biochemistry, radar and antenna design, microelectromechanical sensors, and communication networks in the field of electrical, computer, and mechanical engineering as well as life sciences. The success of this project can lead to significant improvement in the autonomous devices with novel antenna, communication system and nutrient sensor designs to measure signals in the soil at a reasonable cost and are scalable for deployment on a larger scale. The resulting integration of knowledge and expertise from multiple domains, and the generation of new methodologies and data, will provide the means to address pressing societal challenges in sustainable agriculture from a holistic design point of view. The project has potential to forge important new directions for several scholarly and professional disciplines that are oriented toward improving community resilience and train a cohort of undergraduate and graduate students from multiple disciplines to engage in scientific research and create usable scientific tools for stakeholders for a sustainable future.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
