Optimization on theBuried Depth of Subsurface Drainage under Greenhouse Condition Based on Entropy Evaluation Method

Area of Science:

• Agricultural Engineering
• Soil Science
• Agronomy

Background:

• Effective agricultural water conservancy requires careful consideration of plant-soil system indicators.
• The entropy evaluation method shows promise for optimizing agricultural management strategies.

Purpose of the Study:

• To determine the optimal buried depth for subsurface drainage pipes in greenhouse tomato cultivation.
• To assess the impact of varying pipe depths on key plant-soil system indicators.

Main Methods:

• Investigated tomato plant-soil systems with subsurface drainage pipes buried at depths of 30, 45, 60, 75, 90, and 105 cm.
• Evaluated marketable yield, fruit quality (sugar to acid ratio), soil electrical conductivity, nitrogen loss, and crop water and fertilizer use efficiency.
• Applied the entropy evaluation method to determine the optimal pipe burial depth based on weighted indicators.

Main Results:

• Tomato yield and soil electrical conductivity were identified as the most critical indicators, with comprehensive weights of 0.43 and 0.34, respectively.
• The 45 cm buried depth yielded the best overall results, achieving an entropy evaluation value of 0.94.
• At 45 cm depth, soil available nitrogen loss was 13.9%, soil salinity decreased by 49.2%, and tomato yield, sugar to acid ratio, nitrogen use efficiency, and water use efficiency were 112 kg·ha⁻¹, 8.3, 39.7%, and 42.0%, respectively.

Conclusions:

• A 45 cm buried depth for subsurface drainage pipes is optimal for greenhouse tomato production.
• This depth balances crop productivity, quality, and resource use efficiency while mitigating soil degradation.
• The entropy evaluation method provides a robust framework for optimizing agricultural drainage systems.