Tefera et al. (2026) Determination of Crop Water Requirements and Crop Coefficients for Onion Crops Using Lysimeter in the Semi‐Arid Regions of Ethiopia

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Irrigation and Drainage
• Year: 2026
• Date: 2026-04-03
• Authors: Abera Tesfaye Tefera, Tatek Wondimu Negash, Gebeyehu Ashemi Bikela
• DOI: 10.1002/ird.70126

Research Groups

Not explicitly stated in the abstract.

Short Summary

This study established locally calibrated crop coefficient (Kc) values and determined the crop water requirement (CWR) for onion in the semi-arid Central Rift Valley of Ethiopia, finding a seasonal CWR of 472 mm and site-specific Kc values that deviated from standard guidelines.

Objective

• To establish locally calibrated crop coefficient (Kc) values and determine the crop water requirement (CWR) for onion (Allium cepa L.) in the semi-arid climate of the Central Rift Valley of Ethiopia.

Study Configuration

• Spatial Scale: Semi-arid climate of the Central Rift Valley of Ethiopia.
• Temporal Scale: 3-year field experiment (2020–2023).

Methodology and Data

• Models used: Water balance method (applied via lysimeter).
• Data sources: Direct measurement of crop evapotranspiration (ETc) using a drainage-type lysimeter.

Main Results

• The seasonal crop water requirement (CWR) for onion averaged 472 mm over the 3-year study period.
• Derived site-specific crop coefficient (Kc) values were:
  • Initial stage (Days 1–15): 0.55
  • Development stage (Days 15–40): 0.84
  • Mid-season stage (Days 40–75): 1.13
  • Late-season stage (Days 75–97): 0.81
• These local Kc values significantly deviated from standard FAO-56 guidelines, highlighting the influence of local climatic conditions.

Contributions

• Provides locally validated crop coefficient (Kc) values and crop water requirement (CWR) for onion in a specific semi-arid region, which are crucial for developing precise irrigation schedules.
• Enhances water productivity and promotes sustainable intensification of onion production in similar semi-arid areas.
• Underscores the importance of local calibration for Kc values, demonstrating deviations from global standards due to local climatic conditions.

Funding

Not explicitly stated in the abstract.

Citation

@article{Tefera2026Determination,
  author = {Tefera, Abera Tesfaye and Negash, Tatek Wondimu and Bikela, Gebeyehu Ashemi},
  title = {Determination of Crop Water Requirements and Crop Coefficients for Onion Crops Using Lysimeter in the Semi‐Arid Regions of Ethiopia},
  journal = {Irrigation and Drainage},
  year = {2026},
  doi = {10.1002/ird.70126},
  url = {https://doi.org/10.1002/ird.70126}
}