Slopes for each flux — slopes30qua

Slopes of quadratic fit for each flux with 30 seconds end cut and t_zero of 10 seconds, with quality flags. C(t) = a + bt + ct^2

Usage

slopes30qua_flag

Format

A tibble with 1251 rows and 27 variables

f_datetime: Datetime at which CO2 concentration was recorded.
temp_air: Air temperature inside the flux chamber in Celsius.
temp_soil: Ground temperature inside the flux chamber in Celsius.
f_conc: CO2 concentration in ppm.
PAR: Photosynthetically active radiation inside the chamber in micromol/s/sqm.
turfID: Unique ID of the turf in which the measurement took place.
type: Type of measurement: ecosystems respiration (ER) or net ecosystem exchange (NEE).
f_start: Datetime at which the measurement was started.
f_end: Datetime at which the measurement ended.
f_fluxID: Unique ID for each flux.
n_conc: Number of data point per flux.
ratio: Ratio of n_conc over length of the measurement (in seconds).
flag: Data quality flags.
f_time: Time variable of the flux in seconds.
f_cut: Indicating if the measurement should be kept (keep) or discarded (cut).
f_pvalue: P-value of the quadratic model of gas concentration over time.
f_rsquared: R squared of the quadratic model of gas concentration over time.
f_adj_rsquared: Adjusted R squared of the quadratic model of gas concentration over time.
f_intercept: Intercept of the quadratic model of gas concentration over time.
f_param1: b parameter of C(t)
f_param2: c parameter of C(t)
f_slope: Slope of the quadratic model of gas concentration over time at t_zero.
f_fit: Output of the quadratic model of gas concentration over time.
f_fit_slope: output of linear expression describing the slope at t_zero
f_start_error: flagging if measurement started outside of the possible ambient concentration
f_quality_flag: quality flag advising if the slope has to be replaced by 0 or NA
f_slope_corr: slope corrected according to quality flag

Examples

slopes30qua_flag
#> # A tibble: 1,251 × 30
#>    f_datetime          temp_air temp_soil f_conc   PAR turfID       type 
#>    <dttm>                 <dbl>     <dbl>  <dbl> <dbl> <fct>        <fct>
#>  1 2022-07-28 23:43:35    NA         NA     447. NA    156 AN2C 156 ER   
#>  2 2022-07-28 23:43:36     7.22      10.9   447.  1.68 156 AN2C 156 ER   
#>  3 2022-07-28 23:43:37    NA         NA     448. NA    156 AN2C 156 ER   
#>  4 2022-07-28 23:43:38    NA         NA     449. NA    156 AN2C 156 ER   
#>  5 2022-07-28 23:43:39    NA         NA     449. NA    156 AN2C 156 ER   
#>  6 2022-07-28 23:43:40    NA         NA     450. NA    156 AN2C 156 ER   
#>  7 2022-07-28 23:43:41    NA         NA     451. NA    156 AN2C 156 ER   
#>  8 2022-07-28 23:43:42    NA         NA     451. NA    156 AN2C 156 ER   
#>  9 2022-07-28 23:43:43    NA         NA     453. NA    156 AN2C 156 ER   
#> 10 2022-07-28 23:43:44    NA         NA     453. NA    156 AN2C 156 ER   
#> # ℹ 1,241 more rows
#> # ℹ 23 more variables: f_start <dttm>, f_end <dttm>, f_fluxID <fct>,
#> #   n_conc <int>, ratio <dbl>, flag <chr>, f_time <dbl>, f_cut <fct>,
#> #   f_rsquared <dbl>, f_adj_rsquared <dbl>, f_pvalue <dbl>, f_intercept <dbl>,
#> #   f_param1 <dbl>, f_param2 <dbl>, f_slope <dbl>, f_fit <dbl>,
#> #   f_fit_slope <dbl>, f_n_conc <int>, f_ratio <dbl>, f_flag_ratio <chr>,
#> #   f_start_error <chr>, f_quality_flag <chr>, f_slope_corr <dbl>