Li-Cor 6400 photosynthesis measurement

Knowledge graph centered on Li-Cor 6400 photosynthesis measurement with 75 nodes and 168 connections. Top connected: Ipomopsis, Delphinium, I. aggregata, Ipomopsis aggregata, Asteraceae.

Method synopsis

A novel approach to measure light response curves for entire plant communities rather than individual plants using tent-based gas exchange measurements across multiple light levels. This method controls for interspecific variation by measuring community-level responses.

Synthesized from method descriptions across 10 papers using this protocol.

Procedure from a recent peer-reviewed implementation

Steps below were extracted from the most recent peer-reviewed implementation of this protocol in the corpus — <i>In situ</i> photosynthetic freezing tolerance for plants exposed to a global warming manipulation in the Rocky Mountains, Colorado, USA (2004), New Phytologist. The protocol was originally introduced by Plant community light efficiency: measuring light response as a function of both photosynthesis irradiance. (2014). Implementations in other papers (listed below) may differ.

1. Measure photosynthetic gas exchange
   CO2 assimilation, stomatal conductance to water vapor, and transpiration measured using a LI-6400 open-mode portable photosynthesis system. For A. tridentata, three leaves were used and carefully arranged to avoid overlapping; for E. grandiflorum one leaf per plant was used. Chamber CO2 concentration maintained at 360 μmol mol⁻¹ by scrubbing with soda lime
   Quantities: 3 leaves per A. tridentata plant, 1 leaf per E. grandiflorum plant, 360 μmol mol⁻¹ CO2 concentrationDuration: Measurements conducted every 2 h from 0700 to 1800 h at 0730 h for diurnal patternsConditions: Vapor pressure deficit maintained at premeasurement ambient levels, leaf temperatures recorded with copper-constantan thermocouple
   Equipment: LI-6400 open-mode portable photosynthesis system, soda lime, copper-constantan thermocouple, Li-Cor Inc. Lincoln Nebraska USA

Typical Equipment

• LI-Cor 7500 infrared gas analyzer
• tent system
• darkening fabric layers
• reflective blanket
• PAR sensor connected to data logger
• Microsoft Excel

Output Measurements

• light compensation point
• dark respiration rate
• maximum photosynthesis rate
• photosynthesis-irradiance curves

Papers Using This Protocol (10)

Species Studied With This Protocol