Papastamkou et al. (2025) Assessing impacts on irrigated agriculture using an ecosystem-based approach in a Mediterranean reservoir/lake

Identification

• Journal: Journal of Hydrology
• Year: 2025
• Date: 2025-10-21
• Authors: Nikoleta Papastamkou, Charalampos Doulgeris
• DOI: 10.1016/j.jhydrol.2025.134436

Research Groups

• Soil & Water Resources Institute (SWRI), Hellenic Agricultural Organisation, Thessaloniki, Greece

Short Summary

This study investigates the impact of ecosystem-based water management and climate change on irrigation water deficits in Lake Kerkini, Greece, using the MIKE HYDRO Basin model, revealing significant increases in deficits under ecological and climate change scenarios.

Objective

• To evaluate the variation in water level in Lake Kerkini under an ecological approach strategy.
• To assess potential irrigation water shortages in the irrigation networks under an ecological approach strategy.
• To evaluate the above, considering the impact of future challenges related to climate change.

Study Configuration

• Spatial Scale: Lake Kerkini and the Strymonas River basin (16,747 km²), specifically focusing on irrigation networks in the Serres plain, Northern Greece, covering a total irrigated area of 36,459 hectares.
• Temporal Scale: Hydrological years 2014/2015–2018/2019 for data and simulations, with climate change projections up to 2050 for reduced river flow. Model calibration was performed for 2/2015–9/2017 and validation for 10/2017–9/2019.

Methodology and Data

• Models used: MIKE HYDRO Basin modeling system, which includes:
  • FAO 56 Dual Crop Coefficient model for Crop Water Requirement (CWR) calculation.
  • ASCE-standardized Penman-Monteith method for reference evapotranspiration (ETo).
  • NAM rainfall-runoff model for local runoff estimation.
• Data sources:
  • Observed water levels for Lake Kerkini.
  • Water inflow time series for the Strymonas River at the Greece-Bulgaria border from the National Water Monitoring Network.
  • Lake Kerkini level-area-volume data.
  • Environmentally minimum flow release (15.35 m³/s) from the 2nd Revision of River Basin Management Plans.
  • Detailed crop distribution (Maize, Rice, Cotton, Sugar beet, Vegetables/Tomato) and areas for two irrigation user groups (Y1: 14,371 ha; Y2+Y3: 22,088 ha).
  • Irrigation methods (basin, furrow, border strip) and associated water loss coefficients.
  • Basal crop coefficients, maximum crop height, crop development stage lengths, and planting dates.
  • Soil moisture characteristics parameters.
  • Daily meteorological data (rainfall, temperature, reference evapotranspiration) from “Kerkini” and “Kerkinis’ Dum” stations for 2014/2015–2018/2019.
  • Climate change impact data: 25% decrease in Strymonas River outflow by 2050, based on previous studies.

Main Results

• Under the ecosystem-based approach (S2), irrigation water requirements for networks supplied by Lake Kerkini (Y2+Y3) are not fully met, resulting in an annual water demand deficit ranging from above 10% to 30% compared to the business-as-usual scenario (S1).
• Climate change (S3 and S4), modeled as a 25% reduction in Strymonas River outflow, increases the irrigation deficit by almost 10% compared to corresponding scenarios without climate change (S1 and S2).
• In dry years (e.g., 2019), the cumulative effect of the ecosystem-based approach and climate change (S4) can raise the irrigation deficit up to 60% in the irrigation networks supplied by Lake Kerkini (Y2+Y3).
• The ecosystem-based approach (S2) restricts Lake Kerkini's water level fluctuation to approximately 3 meters (from 32 meters to 35 meters above sea level), compared to approximately 4.5 meters (from 30.8 meters to 35.3 meters above sea level) in the business-as-usual scenario (S1).
• Climate change impacts include a retardation of water level rise during autumn-winter and an additional water level fall at the end of the irrigation period, especially under the ecosystem-based approach.

Contributions

• Provides a comprehensive analysis of the impacts of ecosystem-based water management approaches on irrigated agriculture in the Lake Kerkini region, addressing a gap in existing literature.
• Integrates detailed crop data and irrigation methodologies into a hydrological model to evaluate the effects of different water management strategies on agricultural productivity.
• Offers valuable insights for decision-makers to develop adaptive strategies that balance ecological needs with agricultural demands, promoting sustainable water management practices.

Funding

This research received no grant from any funding agency.

Citation

@article{Papastamkou2025Assessing,
  author = {Papastamkou, Nikoleta and Doulgeris, Charalampos},
  title = {Assessing impacts on irrigated agriculture using an ecosystem-based approach in a Mediterranean reservoir/lake},
  journal = {Journal of Hydrology},
  year = {2025},
  doi = {10.1016/j.jhydrol.2025.134436},
  url = {https://doi.org/10.1016/j.jhydrol.2025.134436}
}