Soil Moisture Sensitivity

Soil moisture content is a critical factor that influences plant growth and crop yields. The best measure of moisture is soil moisture tension, a measure of the energy required for plants to extract water from the soil.

Soil Moisture Tension

Soil moisture tension is measured in units of centibars (cb). The lower the soil moisture tension, the more water is available to plants. Soil moisture tension can be divided into three categories:

• Low (0-100 cb): Water is readily available to plants.
• Medium (100-600 cb): Water is increasingly difficult to extract, and plants may begin to experience stress.
• High (above 600 cb): Water is difficult to extract, and plants may wilt or die.

Factors Affecting Soil Moisture Tension

Several factors affect soil moisture tension, including:

• Soil texture: Sandy soils have lower moisture tension than clay soils.
• Organic matter: Organic matter increases soil moisture retention.
• Bulk density: Compacted soils have higher moisture tension than loose soils.
• Evaporation: Evaporation can reduce soil moisture tension by removing water from the soil.
• Transpiration: Transpiration by plants can also reduce soil moisture tension.

Monitoring Soil Moisture Tension

Soil moisture tension can be monitored using tensiometers. Tensiometers are installed in the soil and measure the soil moisture tension. This information can be used to determine when to irrigate and to avoid overwatering or underwatering.

Conclusion

Soil moisture tension is a critical factor that influences plant growth. By understanding soil moisture tension and the factors that affect it, you can optimize irrigation practices to maximize crop yields and prevent water stress.