Prep Verna Wellfield data for use in AD and NPS calculations

Usage

util_prepverna(fl, fillmis = T)

Arguments

fl: text string for the file path to the Verna Wellfield data
fillmis: logical indicating whether to fill missing data with monthly means, see details

Value

A data frame with total nitrogen and phosphorus estimates as mg/l for each year and month of the input data

Details

Raw data can be obtained from https://nadp.slh.wisc.edu/sites/ntn-FL41/ as monthly observations. Total nitrogen and phosphorus concentrations are estimated from ammonium and nitrate concentrations (mg/L) using the following relationships:

$$TN = NH_4^+ * 0.78 + NO_3^- * 0.23$$ $$TP = 0.01262 * TN + 0.00110$$

The first equation corrects for the % of ions in ammonium and nitrate that is N, and the second is a regression relationship between TBADS TN and TP, applied to Verna.

Missing data (-9 values) can be filled using monthly means from the previous five years where data exist for that month. If there are less than five previous years of data for that month, the missing value is not filled.

Years with incomplete seasonal data will be filled with NA values if fillmis = FALSE or filled with monthly means if fillmis = TRUE.

Examples

fl <- system.file('extdata/verna-raw.csv', package = 'tbeploads')
util_prepverna(fl)
#> # A tibble: 504 × 4
#>     Year Month  TNConc   TPConc
#>    <int> <int>   <dbl>    <dbl>
#>  1  1983     1 NA      NA      
#>  2  1983     2 NA      NA      
#>  3  1983     3 NA      NA      
#>  4  1983     4 NA      NA      
#>  5  1983     5 NA      NA      
#>  6  1983     6 NA      NA      
#>  7  1983     7 NA      NA      
#>  8  1983     8 NA      NA      
#>  9  1983     9  0.0101  0.00123
#> 10  1983    10 NA      NA      
#> # ℹ 494 more rows