Abstract: Systems and methods for measuring plant leaf gas exchange based on instantaneous mass balance in the sample chamber. The response of leaf net assimilation rate (Anet) to computed leaf internal CO2 concentration (C1) is measured by continuously varying the input CO2 concentration and measuring the continuous difference between chamber input (reference) and output (sample) concentrations to compute a continuous series of Anet values, which can then be plotted against computed Ci. When combined with a similar response test using an empty chamber test to allow for sample chamber mixing and/or gas analyzer match dynamics and/or small flow-related residual time delays, such method provides accurate and rapid A Ci response (RACiR) curves in a much shorter time than conventional methods.

Abstract: Systems and methods for measuring plant leaf gas exchange based on instantaneous mass balance in the sample chamber. The response of leaf net assimilation rate (Anet) to computed leaf internal CO2 concentration (Ci) is measured by continuously varying the input CO2 concentration and measuring the continuous difference between chamber input (reference) and output (sample) concentrations to compute a continuous series of Anet values, which can then be plotted against computed Ci. When combined with a similar response test using an empty chamber test to allow for sample chamber mixing and/or gas analyzer match dynamics and/or small flow-related residual time delays, such method provides accurate and rapid A Ci response (RACiR) curves in a much shorter time than conventional methods.