Soil water depletion patterns in rainfed apple orchards and wheat fields

Area of Science:

• Agricultural Science
• Hydrology
• Environmental Science

Background:

• Rainfed agriculture in Weibei, Northwest China, faces challenges from drought and water scarcity.
• Land use conversion from crops to orchards is occurring, but its impact on water resources is unclear.

Purpose of the Study:

• To characterize soil water depletion in rainfed orchards and farmlands.
• To evaluate soil desiccation under land use conversion from farmland to orchards.
• To assess the rationality of orchard planting in Weibei's rainfed highland area.

Main Methods:

• Monitoring soil moisture dynamics in different-aged apple orchards and winter wheat fields (0-150 cm depth).
• Measuring soil moisture content monthly via oven-drying during apple growing seasons (March-September 2019).
• Analyzing water over-depletion, depletion patterns, and using a soil desiccation index.

Main Results:

• Water stress occurred in older orchards and farmlands, but was absent in young orchards.
• Older orchards showed deeper and longer soil water depletion than younger ones.
• Soil desiccation was mild in mature/old orchards and absent in young orchards, indicating reduced water stress post-conversion.

Conclusions:

• Conversion from wheat fields to apple orchards mitigates water stress and soil desiccation.
• Orchard planting is a rational land use strategy for Weibei's rainfed highlands.
• Findings support sustainable agro-industrial development models for arid and semi-arid regions.