R code for the blog

DO_clean.R

# Figure 1
# DO - date of sample

WQ %>% 
  ggplot(aes(x = date, y = do.mg.l)) + geom_point() +
  labs(y = 'DO (mg/L)', x = 'Date') +
  theme_grey(base_size = 16)

# Figure 2
# DO - temperature
WQ %>% 
  ggplot(aes(x = temp.c, y = do.mg.l)) + geom_point() +
  labs(y = 'DO (mg/L)', x = quote('Temperature  ' ^o * C)) +
  theme_grey(base_size = 18)


# Figure 3
# Saturated DO as a function of temperature

# The Calc_DOsat100 function is available here
source('https://gist.github.com/TonyLadson/0c7e24d110da3bf3df7d5bf62304a5df')

ggplot(data.frame(x = c(0, 40)), aes(x)) +
  stat_function(fun = Calc_DOsat100, geom = "line") +
  theme_grey(base_size = 18) +
  labs(x = quote('Temperature  ' ^o * C), y = 'Saturated DO (mg/L)')


# Figure 4
# DO-temp with % saturation lines
# Suspect points highlighted


WQ %>% 
  ggplot(aes(x = temp.c, y = do.mg.l)) + geom_point() +
  labs(y = 'DO (mg/L)', x = quote('Temperature  ' ^o * C)) +
  stat_function(fun = Calc_DOsat100, geom = "line", colour = 'blue', linetype = 'dashed') +
  stat_function(fun = function(x) 2* Calc_DOsat100(x), geom = "line", colour = 'blue', linetype = 'dashed') +
  stat_function(fun = function(x) 3* Calc_DOsat100(x), geom = "line", colour = 'blue', linetype = 'dashed') +
  annotate(geom = 'text', x = 35, y = 5, label = '100%', colour = 'blue', hjust = 1) +
  annotate(geom = 'text', x = 35, y = 12, label = '200%', colour = 'blue', hjust = 1) +
  annotate(geom = 'text', x = 35, y = 19, label = '300%', colour = 'blue', hjust = 1) +
  annotate(geom = 'text', x = 35, y = 28, label = '% saturation', colour = 'blue', hjust = 1) +
  annotate(geom = 'rect', xmin = 6, xmax = 16, ymin = 75, ymax = 115, alpha = 0.0, colour = 'red') +
  theme_grey(base_size = 18)
  
# Convert from percent saturation to concentration
# This 
  
  WQ %>% 
  filter(do.mg.l > 60) %>%   # for testing, delete for deployment
  select(do.mg.l, temp.c) %>%  # for testing, delete for deployment
  mutate(do.mg.l_fixed = if_else(do.mg.l > 60, do.mg.l*Calc_DOsat100(temp.c)/100, do.mg.l )) # convert from % saturation to concentration mg/L

# # A tibble: 13 x 3
# do.mg.l temp.c do.mg.l_fixed
# <dbl>  <dbl>         <dbl>
#   1     92.0  10.50     10.263729
# 2     94.0  10.90     10.389630
# 3     91.0  10.60     10.128491
# 4     98.0  11.40     10.707364
# 5     99.0  11.30     10.841546
# 6     86.0   9.00      9.941410
# 7     77.0   8.60      8.987252
# 8    105.0  11.45     11.458999
# 9    102.0  11.60     11.093355
# 10    96.0  10.60     10.685001
# 11    98.3  11.14     10.804696
# 12   111.4  14.80     11.282098
# 13    87.1  15.10      8.764121