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Comprehensive framework for interpretation of WaPOR water productivity
Shadman Veysi1, Eslam Galehban2, Milad Nouri1
1Soil and Water Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran.
Heliyon
|September 9, 2024
Summary
Mapping crop types is crucial for accurate water productivity analysis. A new dimensionless index reveals rainfed cereals as highly water-productive, guiding better water management in semi-arid regions.
Area of Science:
- Agricultural Science
- Hydrology
- Remote Sensing
Background:
- The FAO Water Productivity Open-access portal (WaPOR) provides valuable water productivity data.
- Existing indices like Gross Water Productivity (GWP) and Net Water Productivity (NWP) aggregate crop types, potentially misleading decision-making.
- Water scarcity in semi-arid regions necessitates refined water productivity assessments.
Purpose of the Study:
- To develop a comprehensive framework for analyzing WaPOR water productivity products.
- To introduce a dimensionless index for comparing water productivity across different crops.
- To enhance the interpretation of water productivity data through crop-type mapping.
Main Methods:
- Analysis of WaPOR data for crops in rainfed and irrigated areas of a semi-arid basin in Iran.
- Introduction and application of Gross Water Productivity (GWP) and Net Water Productivity (NWP) indices.
- Development and utilization of a dimensionless water productivity index, integrated with crop-type mapping.
Main Results:
- A significant divergence was observed between traditional GWP/NWP indices and the derived dimensionless water productivity.
- Pixels initially showing high GWP/NWP values were sometimes identified as low-productivity using the dimensionless index.
- Rainfed crops, especially cereals, demonstrated the highest water productivity based on the dimensionless indicators.
Conclusions:
- Mapping crop types is essential for accurate water productivity interpretation and comparison.
- The dimensionless index provides a more nuanced understanding of crop water productivity than GWP and NWP.
- Areas with dimensionless values below 0.5 require targeted interventions to reduce water waste and improve productivity, particularly in semi-arid environments.
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