The structure of this repository is composed of a starting script, and a set of 5 modules, each of which contain a set of python files. The following elements are described here:
- the python file
fra_start.py: A starting script that triggers the assessment - the module
CONFIG: An Excel file that is used to provide paths and parameters for the assessment - the module
SCRIPTS: A module with scripts for automating the processing of scenarios - the module
INDICES: A module with algorithms to calculate the indices (DOF, DOR, SED, DOM, STA) - the module
STATS: A module to calculate statistics, and to conduct the benchmarking - the module
TOOLS: A helper module with geoprocessing tools
4.1 Python file fra_start.py
The start of the assessment is triggered by running the python file fra_start.py from a command line editor or through a programming environment, such as Pycharm. The script reads the configuration file (config.xlsx), establishes which components of the assessment are to be executed, and creates an output directory structure for the results.
4.2 Module ‘config’
The configuration file config.xlsx, located in the folder config, provides the main parameters for the analysis, and serves two main purposes:
- It provides parameter settings for the model run, for example settings to control the Degree of Fragmentation (
DOF) analysis. It furthermore provides input data and output folder paths (see sheetSET_GLOinconfig.xlsx). - It provides the spreadsheet where existing scenarios are defined and weights to individual pressure indicators are allocated (see sheet
SCE_100inconfig.xlsx).
4.2.1 Settings
The sheet SET_GLO in config.xlsx provides an example settings file, with a number of relevant parameter settings. These include path settings, general settings, and settings related to DOF, DOR, and SED calculations. The table contains the four columns Category, Key, Value, and Description. See the spreadsheet for more information on the keys and their function.
4.2.2 Scenarios
The individual scenarios are defined in the worksheet SCE_100 in config.xlsx. Under this header row, each additional row corresponds to a distinct scenario. One hundred predefined scenarios already exist in the template spreadsheet. Another 22 scenarios exist for conducting sensitivity analysis. The following columns are present and explained below:
| Field name | Descriptions |
|---|---|
| Scenario_name | Provides the name of the Scenario. Please keep this name very simple (preferably something like ‘CSI01’; CSI02 etc.), and under 10 characters, do not use blanks or special characters, and do not start the name with a number. |
| Indicator_1 to Indicator_6 | These refer to pressure indicators to be used in the scenario. The name given here must reflect the field names in the input streams feature class in the geodatabase. |
| Weight_1 to Weight_6 | These are the weights assigned to each pressure indicator. The sum of the weights should equal to 100%, otherwise there may be a distortion. |
| CSI_threshold | The field defines the CSI threshold to use for determining the FFR status (0-100%). |
| Fld_damp | This parameter determines the strength of the floodplain weighting (0-100%). |
| filter_thresh | Provides a parameter for filtering extreme outliers (% of total flow of river affected) |
| to_process | Determines if the scenario is to be included in the model run (0 or 1) |
| to_export | Determines if a result table and feature class will be produced (0 or 1) |
4.3 Module “scripts”
The python files in this module are triggered by the start script fra_start.py and each execute a series of functions and algorithms to calculate the DOF, DOR, and SED, respectively. The python scripts rely on functions defined in the modules “indices” and “stats”.
4.4 Module “indices”
The python files here provide source code related to calculating the main indices, i.e. DOF, DOR, and SED
4.5 Module “stats”
This module contains functions to perform benchmarking, sensitivity analysis, and to create statistics.