Transpiration-Based CWSI: A More Accurate Approach to Crop Water Stress Assessment
This article builds upon my previous work on canopy temperature measurements and the Crop Water Stress Index (CWSI), and I highly recommend reading " Decoding VPD and CWSI for Optimized Crop Water Management " before continuing. My research has focused on two key challenges in the conventional CWSI approach: the calculation of CWSI itself, and how it's applied to irrigation scheduling (the CWSI algorithm). I've developed improvements in both areas, specifically by using a transpiration-based CWSI calculation and a dynamic threshold algorithm. These enhancements are detailed below. CWSI Definitions Traditional CWSI Definition As discussed previously, CWSI is traditionally defined as: CWSI = (ΞTm - ΞTl) / (ΞTu - ΞTl) where ΞTm is the measured canopy-to-air temperature difference, ΞTl is the temperature difference under non-limiting soil water availability (well-watered plant canopy), and ΞTu is the temperature difference for a non-transpiring canopy (dead plant)....