Correlating grain yield with irrigation in a spatio-temporal context on the North China Plain

Area of Science:

• Agricultural Science
• Environmental Science
• Geospatial Analysis

Background:

• Irrigation is vital for agricultural productivity, but its spatiotemporal relationship with grain yield is complex and often overlooked.
• Understanding these dynamics is crucial for optimizing irrigation strategies and ensuring food security.

Purpose of the Study:

• To analyze the spatiotemporal patterns and evolution of the relationship between grain yield and irrigation in the North China Plain (NCP).
• To identify regional disparities and provide data-driven recommendations for effective irrigation management.

Main Methods:

• Time series analysis to track changes over time.
• Geographic Information System (GIS) spatial analysis for regional patterns.
• Geographically Weighted Regression (GWR) to model local relationships between yield and irrigation.

Main Results:

• Grain yields are higher in northern NCP, with regional variations. Maize yields slightly exceed wheat yields.
• Irrigation decreased in nearly half of the study area since 2004. Both yield and irrigation show spatial aggregation.
• The correlation between wheat yield and irrigation increased slightly, while maize yield's correlation decreased significantly. The positive impact of irrigation on yield has diminished since 2002.

Conclusions:

• Irrigation's effectiveness varies significantly across the NCP, with its positive impact on grain yield declining.
• Region-specific strategies, including sprinkler irrigation, deficit irrigation, and water-saving technologies, are recommended.
• Sustainable agricultural practices require a combination of optimized irrigation, improved crop varieties, and sound agricultural management to ensure food security and water resource sustainability.