Integration of Heat Capacity and Electrical Conductivity Sensors for Root Module Water and Nutrient Assessment 2006-01-2211
Management of water content and nutrient status during space flight is a critical element for successful plant production systems. Our objectives were to determine if dual-probe heat-pulse (DPHP) sensors could improve water content determination accuracy over single-probe heat-pulse (SPHP) sensors, and to test a design using coupled heat-pulse and direct-current electrical conductivity sensors, paired as a 4-electrode array. The DPHP predicted water content correlated well with independently measured water contents based on a physically-derived one-point calibration model. SPHP water content prediction was comparable to the dual-probe sensors when using an empirical relationship. Pooled regression analysis showed that water content for both sensors was accurate with a root-mean square error of 0.02 cm3 cm−3. Electrical conductivity was measured in both saturated flow-through and static unsaturated measurements. Model predictions of solution electrical conductivity as a function of water contents were well correlated for water contents above 0.2 cm3 cm−3. Combining the dual-needle heat-pulse probe water content determination with electrical conductivity measurements provides improved root-zone environment assessment and management capabilities.
Citation: Heinse, R., Lewis, K., Jones, S., Kluitenberg, G. et al., "Integration of Heat Capacity and Electrical Conductivity Sensors for Root Module Water and Nutrient Assessment," SAE Technical Paper 2006-01-2211, 2006, https://doi.org/10.4271/2006-01-2211. Download Citation
Robert Heinse, Kelly S. Lewis, Scott B. Jones, Gerard Kluitenberg, Richard S. Austin, Peter J. Shouse, Gail E. Bingham
Department of Plants, Soils and Biometeorology, Utah State University
International Conference On Environmental Systems