Study on the Suitable Area of Ratoon Rice in China Under Climate Change

Area of Science:

• Agricultural Science
• Climate Change Adaptation
• Crop Physiology

Background:

• Ratoon rice cultivation leverages the regenerative capacity of rice axillary buds for double harvests.
• This system relies on specific agronomic practices to stimulate stubble bud regeneration.
• Understanding environmental suitability is crucial for expanding this efficient farming method.

Purpose of the Study:

• To predict the suitable cultivation areas for ratoon rice in China under current and future climate scenarios.
• To identify key environmental factors influencing ratoon rice distribution.
• To project changes in suitable ratoon rice areas due to climate change.

Main Methods:

• Utilized 167 occurrence records of ratoon rice and nine environmental variables.
• Employed the MaxEnt model to predict suitable cultivation areas.
• Incorporated three CMIP6 climate scenarios (SSP1-2.6, SSP2-4.5, SSP5-8.5) for future projections.

Main Results:

• Key factors influencing ratoon rice distribution include accumulated temperature, growth period length, altitude, and precipitation.
• Current suitable areas are primarily south of the Qinling-Huaihe line.
• Future climate scenarios project an increase in suitable ratoon rice areas, particularly in the middle and lower Yangtze River regions.

Conclusions:

• Ratoon rice cultivation is projected to expand northward with climate change, though autumn temperatures remain a limiting factor.
• Specific regions like southern Hunan and central Hubei show high potential for future ratoon rice expansion.
• Prioritizing these newly suitable areas can enhance ratoon rice cultivation efficiency.