摘要
Drought is one of the main factors limiting the agricultural planting and production;gravel mulching is an effective inhibiting evaporation and water-saving planting pattern in the arid regions. In this study, experiments were conducted to study soil moisture effect and regression model with different gravel mulching, the soil moisture content and evaporation were compared that gravel mulched with different particle sizes, different thickness layer and different mulched years. The results showed that: 1) The cumulative soil evaporation of gravel mulched was only 29.3% of that bare fields. Mulching gravel could significantly reduce soil moisture evaporation. 2) The effects of inhibiting soil moisture evaporation are the best when mulch gravel thickness is 10 - 15 cm. 3) The particle size of gravel mulched is smaller, the evaporation inhibition effect will be better. Considering the water holding capacity and material economy, it is the most suitable to mulch gravel with the particle size of 3 - 5 cm. 4) Mulching gravel on the soil surface for 1 - 3 years can improve the soil moisture content. However, the gravel was mulched for more than five years, the soil moisture content decreased significantly. 5) The quadratic polynomial regression fitting model can better simulate and predict the cumulative evaporation on different gravel mulched, and the regression fitting degree R<sup>2</sup> is more than 0.98.
Drought is one of the main factors limiting the agricultural planting and production;gravel mulching is an effective inhibiting evaporation and water-saving planting pattern in the arid regions. In this study, experiments were conducted to study soil moisture effect and regression model with different gravel mulching, the soil moisture content and evaporation were compared that gravel mulched with different particle sizes, different thickness layer and different mulched years. The results showed that: 1) The cumulative soil evaporation of gravel mulched was only 29.3% of that bare fields. Mulching gravel could significantly reduce soil moisture evaporation. 2) The effects of inhibiting soil moisture evaporation are the best when mulch gravel thickness is 10 - 15 cm. 3) The particle size of gravel mulched is smaller, the evaporation inhibition effect will be better. Considering the water holding capacity and material economy, it is the most suitable to mulch gravel with the particle size of 3 - 5 cm. 4) Mulching gravel on the soil surface for 1 - 3 years can improve the soil moisture content. However, the gravel was mulched for more than five years, the soil moisture content decreased significantly. 5) The quadratic polynomial regression fitting model can better simulate and predict the cumulative evaporation on different gravel mulched, and the regression fitting degree R<sup>2</sup> is more than 0.98.
