Improved grazing management may increase soil carbon sequestration in temperate steppe

Area of Science:

• Ecology
• Soil Science
• Agronomy

Background:

• Grazing management significantly influences grassland ecosystems.
• Understanding its impact on soil carbon sequestration is crucial for climate change mitigation.

Purpose of the Study:

• To investigate how different grazing strategies affect soil carbon sequestration in a semiarid temperate steppe.
• To determine optimal grazing parameters for maximizing carbon accrual.

Main Methods:

• Studied combinations of rest, high, and moderate grazing over three growing season stages.
• Analyzed root production, turnover, soil nitrogen retention, and microbial environment.
• Utilized regression analysis to identify optimal stocking rates and vegetation utilization.

Main Results:

• Constant moderate grazing (MMM) resulted in the highest root production and soil carbon accumulation.
• Deferred grazing (RHM, RMH) showed higher root mass and better nitrogen retention but less carbon sequestration than MMM.
• Constant high grazing (HHH) reduced plant production, increased nitrogen loss, and negatively impacted the soil microbial environment.

Conclusions:

• Grazing regimes critically affect soil carbon sequestration in temperate grasslands.
• Adjusting stocking rates to approximately 5 Animal Units/ha with 40% vegetation utilization optimizes carbon accrual.
• Grazing management can be adapted to enhance soil carbon sequestration in temperate steppe ecosystems.