Simulating the potential effects of elevated CO₂ concentration and temperature coupled with storm intensification on crop yield, surface runoff, and soil loss based on 25 GCMs ensemble: A site-specific case study in Oklahoma

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##   This python script was developed to record the output of the WEPP model running      ##

##   under a single slope and soil condition with various combinations of climate change  ##

##   senarios and management controls. It was customized to conduct a scientific project  ##

##   at USDA-ARS Grazinglands Research Lab. El Reno, OK 73036.                            ##

##                                                                                        ##

##   Author: Lifeng Yuan                                                                  ##

##   Email: Lifeng.Yuan@ou.edu                                                            ##

##   Date: October 2020                                                                   ##

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PyLink_WEPP Python Script

import os

import subprocess

# Define paths using raw strings to avoid escaping backslashes

path_output = r"c:\wepp\output\Present"

path_man = r".\managements"

path_cli = r".\Data\climates\Present"

# Function to get filenames from a directory

def get_filenames(directory):

    os.chdir(directory)

    filenames = []

    for _, _, files in os.walk('.\\'):

        filenames.extend(files)

    return filenames

# Get management and climate filenames

mans_filename = get_filenames(r'c:\wepp\python\managements')

clis_filename = get_filenames(r'c:\wepp\Data\climates\Present')

# Print management and climate files

print("Management Files:", mans_filename)

print("Climate Files:", clis_filename)

# Set up running years for WEPP

years = 100

# Function to run WEPP model

def run_wepp(man_file, cli_file):

    wepp_executable = r"C:\WEPP\wepp\wepp_co2_2019.exe"

    inputs = [

        "m\n",  # Measurement units

        "y\n",  # Hillslope option

        "1\n",  # Continuous simulation

        "1\n",  # Hillslope version

        "n\n",  # Hillslope pass file

        "1\n",  # Abbreviated annual output

        "n\n",  # Initial condition scenario output

        f"{path_output}\\sol_{man_file[:-4]}_{cli_file[:-4]}.txt\n",

        "y\n",  # Water balance output

        f"{path_output}\\wat_{man_file[:-4]}_{cli_file[:-4]}.txt\n",

        "n\n",  # Plant and residue output

        "n\n",  # Soil output

        "n\n",  # Distance and sediment loss output

        "n\n",  # Large graphics output

        "y\n",  # Event output

        f"{path_output}\\evt_{man_file[:-4]}_{cli_file[:-4]}.txt\n",

        "n\n",  # Element output

        "y\n",  # Final summary

        f"{path_output}\\sum_{man_file[:-4]}_{cli_file[:-4]}.txt\n",

        "n\n",  # Daily winter output

        "y\n",  # Crop yield output

        f"{path_output}\\crp_{man_file[:-4]}_{cli_file[:-4]}.txt\n",

        f"{path_man}\\{man_file}\n",

        "fr5.slp\n",  # Slope file

        f"{path_cli}\\{cli_file}\n",

        "FR678_945.sol\n",  # Soil data

        "0\n",  # No irrigation

        f"{years}\n",

        "0\n"  # Route all events

    ]

    try:

        result = subprocess.run(

            [wepp_executable],

            input=''.join(inputs),  # Join the list into a single string

            text=True,

            capture_output=True,

            check=True

        )

        print(f"WEPP run successfully for {man_file} and {cli_file}")

    except subprocess.CalledProcessError as e:

        print(f"Error running WEPP for {man_file} and {cli_file}: {e.stderr}")

# Run WEPP for each combination of management and climate files

for man_file in mans_filename:

    for cli_file in clis_filename:

        run_wepp(man_file, cli_file)