日光温室蔬菜栽培对土壤团聚体稳定性的影响——以陕西省泾阳县日光温室土壤为例

EFFECTS OF SOLAR GREENHOUSE VEGETABLE CULTIVATION ON SOIL AGGREGATES STABILITY——A CASE STUDY OF SOLAR GREENHOUSE SOIL IN JINGYANG COUNTY,SHAANXI PROVINCE

土壤的团聚状况是土壤重要的物理性质之一,团聚体的数量是衡量和评价土壤肥力的重要指标。用干筛法、湿筛法及带水振荡法对日光温室土壤和露地土壤的团聚体含量进行了测定,并进行了比较。根据干筛法测得的各级团聚体含量及平均重量直径(MWD)的评判,日光温室土壤大于10 mm团聚体的机械稳定性低于露地土壤。根据大于0.25 mm水稳性团聚体含量、水稳性团聚体的MWD值、团聚体的破坏率及团聚体的原始稳定系数和崩解速率等指标评判,日光温室土壤团聚体的水稳性高于露地土壤。日光温室蔬菜栽培年限长于5 a后,土壤中团聚体的机械稳定性显著降低,水稳性显著提高。

Aggregates status of soil was an important soil physical properties, and the amount of soil aggregates is an important index for measuring and evaluating soil fertility. Aggregates of soils inside and outside the greenhouse were measured with the dry-sieving method, the wet-sieving method and water-oscillating method for comparison. Based on contents of aggregates of different fractions and mean weight diameter （MWD） determined with the dry-sieving method, analysis showed that mechanical stability of the aggregates of the fraction 〉 10 mm was higher in soils inside the greenhouse than outside the greenhouse. Based on contents of water stable aggregates 〉 0.25 mm, MWD of water-stable aggregates, breakage rate, initial stability coefficient and disintegrating rate of aggregates, analysis revealed that the soil inside the greenhouse was higher than the soil outside in water stability. Greenhouse cultivation longer than 5 years significantly decreased mechanical stability of soil aggregates, but affected reversely their water stability.