山西设施栽培条件下土壤理化性质的变化规律

Changes of soil physical and chemical characters under greenhouses cultivation in Shanxi Province

测定了山西设施栽培条件下不同种植年限耕层土壤的理化性质。结果表明,设施栽培条件下土壤有机质、电导率、全量养分(全氮、全磷和全钾)和速效养分(碱解氮、速效磷和速效钾)含量与种植年限均呈二次多项式关系,且相关关系达显著或极显著水平。土壤有机质含量较低,生产中应增加有机肥的施用量;全氮、全磷盈余,全钾耗亏,全量养分关系失衡成为土壤肥力提高的障碍因子;速效养分累积明显;土壤pH值明显低于大田土壤,有酸化趋势;土壤电导率较高,但未达到严重影响作物生长发育的水平。表明设施土壤理化性状和各种形态养分的动态变化可能会导致土壤功能发生转变。

The physical and chemical characters and the nutrient contents in top soils greenhouses in different parts of Shanxi Province were determined to evaluate the changes of the soil fertility. The results showed that there were significantly quadratic relationships between the cultivating years and organic matter,total nutrients（total N,P and K） and available nutrients（available N,P and k） content,and electric conductivity. The total N,and P in greenhouse soils increased,but the total K decreased,which indicated new challenge of soil fertility under greenhouse cultivation. The available nutrients in greenhouse soil were higher than that of open-land. The organic matter in greenhouse soils was still low compared with the high productivity greenhouse soil,and the soil pH was lower than that of open-land,indicating the acidification of the soils under greenhouse condition. The electric conductivity in greenhouse soil increased significantly, but it didn ＇t reach the harmful level to the plant growth and development. Therefore, more attention should be paid to the application of organic fertilizers. It is suggested that the dynamic transformation of soil physical and chemical properties and nutrients may lead to the transformation of soil function.