pam (version 2.0.2)

walsby_generate_regression_ETR_II: Walsby Regression for ETR II

Description

Fits a modified Walsby (1997) regression model without the respiration term, using Romoth (2019) naming conventions. Calculates \(ETR_{max}\) without accounting for photoinhibition.

Usage

walsby_generate_regression_ETR_II(
  data,
  etr_max_start_value = walsby_default_start_value_etr_max,
  alpha_start_value = walsby_default_start_value_alpha,
  beta_start_value = walsby_default_start_value_beta
)

Value

A list containing:

• etr_regression_data: Predicted ETR values.

• residual_sum_of_squares: Difference between observed and predicted ETR values, expressed as the sum of squared residuals.

• root_mean_squared_error: Difference between observed and predicted ETR values, expressed as the root mean squared error.

• relative_root_mean_squared_error: Difference between observed and predicted ETR values, expressed as the relative root mean squared error, normalized by the mean.

• etr_max: Maximum ETR (\(ETR_{max}\)).

• alpha: Initial slope (\(\alpha\)).

• beta: Photoinhibition factor (\(\beta\)).

Arguments

data

A data.table from read function (e.g.read_dual_pam_data).

etr_max_start_value

Numeric. Initial value for \(ETR_{max}\). Default: etr_max_start_value_walsby_default.

alpha_start_value

Numeric. Initial value for \(\alpha\). Default: alpha_start_value_walsby_default.

beta_start_value

Numeric. Initial value for \(\beta\). Default: beta_start_value_walsby_default.

Details

A detailed documentation can be found under https://github.com/biotoolbox/pam?tab=readme-ov-file#walsby_generate_regression_etr_i-and-walsby_generate_regression_etr_ii.

References

Walsby, A. E. (1997). Numerical integration of phytoplankton photosynthesis through time and depth in a water column. New Phytologist, 136(2), 189-209. Available at: tools:::Rd_expr_doi("10.1046/j.1469-8137.1997.00736.x")Romoth, K., Nowak, P., Kempke, D., Dietrich, A., Porsche, C., & Schubert, H. (2019). Acclimation limits of Fucus evanescens along the salinity gradient of the southwestern Baltic Sea. Botanica Marina, 62(1), 1-12. Available at: tools:::Rd_expr_doi("10.1515/bot-2018-0098")

Examples

path <- file.path(system.file("extdata", package = "pam"), "20240925.csv")
data <- read_dual_pam_data(path)

result <- walsby_generate_regression_ETR_II(data)