peatland-time-series 0.1.9

Analyze water retention in peatland from time series of precipitation and water table depth

Peatland Time Series

This Python library contains functions which make it possible to analyze the water retention in a peatland from time series of precipitation and water table depth.

Installation

pip install peatland-time-series

Usage

Calculating the Specific Yield (Sy)

The calculate_sy function allows you to calculate the specific yield (Sy) from a time series of precipitation and the water table depth.

Lets take the example of a CSV file ./data/time-series.csv, a time-series of precipitation and water table depth. The table must have at least the columns "date", "data_prec" and "data_wtd". There is an example of CSV file:

date,data_prec,data_wtd
2011-06-16 12:00:00,-0.098,0
2011-06-16 13:00:00,-0.103,0
2011-06-16 14:00:00,-0.109,10.3
2011-06-16 15:00:00,-0.089,0
2011-06-16 16:00:00,-0.084,0

To calculate the Sy with other pertinent information:

import pandas
from peatland_time_series import calculate_sy, read_time_series, visualization

time_series = read_time_series('./data/time-series.csv')

result = calculate_sy(time_series)
print(results.head())

Output:

       date_beginning         date_ending  precision_sum  max_wtd  min_wtd  durations  intensities  delta_h   depth        sy             idx_max             idx_min  accuracy_mean  accuracy_std
0 2011-06-16 14:00:00 2011-06-16 14:00:00           10.3   -0.084   -0.109        0.5         20.6    0.025 -0.0965  0.412000 2011-06-16 16:00:00 2011-06-16 14:00:00       0.001333      0.003317
1 2011-06-16 20:00:00 2011-06-16 21:00:00            3.7   -0.072   -0.100        1.0          3.7    0.028 -0.0860  0.132143 2011-06-16 23:00:00 2011-06-16 20:00:00       0.000000      0.000000
2 2011-06-18 04:00:00 2011-06-18 05:00:00            1.2   -0.067   -0.084        1.0          1.2    0.017 -0.0755  0.070588 2011-06-18 04:00:00 2011-06-18 09:00:00       0.000000      0.000000
3 2011-06-18 12:00:00 2011-06-18 12:00:00            0.4   -0.085   -0.094        0.5          0.8    0.009 -0.0895  0.044444 2011-06-18 12:00:00 2011-06-18 15:00:00       0.001556      0.002603
4 2011-06-18 17:00:00 2011-06-18 17:00:00            1.6   -0.077   -0.087        0.5          3.2    0.010 -0.0820  0.160000 2011-06-18 18:00:00 2011-06-18 17:00:00       0.000667      0.001000

Plotting water level in function of the time

time_series = read_time_series('path/to/time-series.csv')
sy = calculate_sy(time_series)

visualization.show_water_level(
    time_series,
    sy,
    event_index=30,
    time_before=pandas.Timedelta(hours=10),
    time_after=pandas.Timedelta(hours=20)
)

Output:

For more information, see the visualization.show_water_level docstring.

Plot depth(Sy)

It is possible to plot the depth in function of Sy. Note that the Sy DataFrame can by filtered with the filter_sy function.

time_series = read_time_series('path/to/time-series.csv')
sy = calculate_sy(time_series=time_series)
sy = filter_sy(sy, sy_min=0, delta_h_min=.01, precipitation_sum_min=10, precipitation_sum_max=100)

visualization.show_depth(sy, heigh_of_file=-3)

Output:

Interactively select data points.

The visualization.show_depth(..., select=True) function plots an interactive selector of the Depth(Sy) graph. You can click on the data points you wish to exclude. A set of indexes of the selected data points is returned.

selected_indexes = show_depth(sy, select=True)

# selected_indexes
{0, 100, 5, 101, 103, 46, 79, 47, 19, 24}

Reference / Citation

We kindly ask users who produce scientific works to cite the following paper when using this library or algorithms : Quantification of peatland water storage capacity using the water table fluctuation method (https://doi.org/10.1002/hyp.11116)