Does settlement land expansion necessarily induce the decrease of cultivated land? Differences in national scale and...

Area of Science:

• Environmental Science
• Geography
• Urban Planning

Background:

• China's rapid industrialization and urbanization have led to significant land-use changes.
• The dynamic interplay between settlement land (SL) expansion and cultivated land (CL) loss requires detailed investigation.
• Understanding these changes is crucial for balancing national development with food security.

Purpose of the Study:

• To investigate the long-term trends in quantity and spatial patterns of SL expansion and CL change in China.
• To analyze these trends at both national and local scales.
• To propose a zoning framework to identify trade-off and synergy relationships between SL expansion and CL change.

Main Methods:

• Utilized yearly ESA CCI land use and land cover products from 1992 to 2020.
• Employed trend statistic methods to analyze temporal and spatial changes.
• Developed a comprehensive zoning framework to classify local counties based on land-use change relationships.

Main Results:

• Observed continuous SL expansion with significant breakpoints in 2000, 2005, and 2012.
• Documented a fluctuating decline in CL with breakpoints in 1997, 2002, 2006, and 2013.
• Identified distinct spatial patterns: SL concentrated around urban areas, while CL showed a planar, continuous distribution. Most local counties exhibited trade-off relationships, with synergies being rare.

Conclusions:

• National trends in SL expansion and CL change mask significant local variations and trade-offs.
• A few counties showed synergistic relationships, but most in central-east and western China faced trade-offs.
• Findings underscore the need for differentiated land-use management policies to ensure food security and sustainable development.