/IHA_parameters

Indicators of hydrological alteration calculated in Tesfalem et al. (2023, J.hydrol; Reg studies) The 32 IHA parameters describe the whole range of ecologically significant aspects of the flow regime, such as magnitude, frequency, timing, duration, and rate of change.

Primary LanguageMATLABGNU General Public License v3.0GPL-3.0

IHA_parameters

Indicators of hydrological alteration calculated in Tesfalem et al. (2023, J.hydrol; Reg studies) The 32 IHA parameters describe the whole range of ecologically significant aspects of the flow regime, such as magnitude, frequency, timing, duration, and rate of change.

This README file contains the description of those 32 IHA parameters utilized in the current study of Abraham et al. (2023). The 32 IHA parameters are adopted from Richter et al. (1996). They describe the whole range of ecologically significant aspects of the flow regime, such as magnitude, frequency, timing, duration, and rate of change.

The 32 IHA parameters are grouped into five such as: • Group 1- monthly flow indices, • Group 2 - extreme flow indices, • Group 3 - timing indices, • Group 4 - high-flow and low-flow indices and • Group 5 - rising and falling indices.

Description of each 32 IHA parameters is shown below, and more extended description can be found in Abraham et al. (2023).

IHA statistics groups and Hydrologic parameter (Short form) Group 1: Magnitude of monthly water condition Jan, Feb...Dec

Group 2: Magnitude and duration of annual extreme water condition 1d_min 1d_max 3d_min 3d_max 7d_min 7d_max 30d_min 30d_max 90d_min 90d_max

Group 3: Timing of annual extreme water condition Julian date of max Q Julian date of min Q

Group 4: Frequency and duration of high and low pulses high pulses count low pulses count high pulses duration low pulses duration

Group 5: Rate and frequency of water condition changes mean of all +ve diff mean of all –ve diff number of rise number of fall

We provided a code to calculate all the above 32 IHA parameters in the MATLAB code. There are five MATLAB codes to calculate the five groups of IHA as Group1.mat, Group2.mat, Group3.mat, Group4.mat, Group5.mat. In these codes we calculated the IHA parameters for one gauged catchment (#01 @Bilate) using streamflow time series data in the historical period (1995-2007).

language: Matlab

included files: - IHA calculation code: Group1.mat, Group2.mat, Group3.mat, Group4.mat, Group5.mat. - Input streamflow data for catchment #01 in the historical period: Qobs1995_2007.mat - Calculated IHA parameters: Group1_IHA.mat, Group2_IHA.mat, Group3_IHA_Adjusted.mat, Group4_IHA.mat, Group5_IHA.mat

Reference

Abraham, T., Liu, Y., Tekleab, S., Hartmann, A., 2023. Climate change potentially induces ecological change in the Ethiopian Rift Valley Lakes Basin. Journal of hydrol; regional studies. Richter, B.D., Baumgartner, J. V., Powell, J., Braun, D.P., 1996. A Method for Assessing Hydrologic Alteration within Ecosystems. Conserv. Biol. 10, 1163–1174. https://doi.org/10.1046/j.1523-1739.1996.10041163.x