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Arrhenius parameters describing the temperature response of important C3 photosynthetic parameters, intended to be passed to the calculate_arrhenius function.

Usage

c3_arrhenius_bernacchi

Format

List with 7 named elements that each represent a variable whose temperature-dependent value can be calculated using the Arrhenius equation:

  • RL_norm: The respiration rate (RL) normalized to its value at 25 degrees C.

  • Vcmax_norm: The maximum rate of rubisco carboxylation (Vcmax) normalized to its value at 25 degrees C.

  • Vomax_norm: The maximum rate of rubisco oxygenation (Vomax) normalized to its value at 25 degrees C.

  • Gamma_star: The value of CO2 partial pressure in the chloroplast at which no assimilation occurs in the absence of respiration.

  • Kc: The Michaelis-Menten constant for rubisco carboxylation.

  • Ko: The Michaelis-Menten constant for rubisco oxygenation.

  • J_norm: The electron transport rate (J) normalized to its value at 25 degrees C.

In turn, each of these elements is a list with 3 named elements:

  • c: the (dimensionless) Arrhenius scaling factor.

  • Ea: the activation energy in kJ / mol.

  • units: the units of the corresponding variable.

Source

Some of these parameters (RL, Vcmax, and J) are normalized to their values at 25 degrees C. Vomax is normalized to the value of Vcmax at 25 degrees C. These variables include _norm in their names to indicate this.

The remaining parameters (Gamma_star, Kc, and Ko) are not normalized because they are assumed to not vary significantly between species.

Arrhenius parameters for J were obtained from Bernacchi et al. (2003). Here, we use the values determined from chlorophyll fluorescence measured from plants grown at 25 degrees C (Table 1). Although Bernacchi et al. (2003) reports values of Jmax, here we assume that both Jmax and the light-dependent values of J follow the same temperature response function and refer to it as J for compatibility with c3_arrhenius_sharkey.

The Arrhenius parameters for the other variables were obtained from Bernacchi et al. (2001).

References:

  • Bernacchi, C. J., Singsaas, E. L., Pimentel, C., Jr, A. R. P. & Long, S. P. "Improved temperature response functions for models of Rubisco-limited photosynthesis" Plant, Cell & Environment 24, 253–259 (2001) [doi:10.1111/j.1365-3040.2001.00668.x ].

  • Bernacchi, C. J., Pimentel, C. & Long, S. P. "In vivo temperature response functions of parameters required to model RuBP-limited photosynthesis" Plant, Cell & Environment 26, 1419–1430 (2003) [doi:10.1046/j.0016-8025.2003.01050.x ].