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对哈尔滨市和大庆市不同种植年限的大棚土壤取样 ,调查结果表明 :( 1)随着种植年限的增加 ,土壤水稳性团聚体 ( 5～ 0 .2 5m m)的数量增加 ,毛细管孔隙发达 ,持水性变好 ;通气透水性变差。 ( 2 )种植 5年以上的大棚土壤与露地土壤比较有机质和全氮含量明显增加 ,达极显著水平 ;速效氮明显增加 ,达显著水平 ;速效磷呈高度富集状态 ;速效钾的变化因地区而异 ,哈尔滨市无明显变化 ,大庆市呈富集状态 ;p H值有随种植年限的增加而下降的趋势。 ( 3)哈尔滨市种植 8年以上的大棚土壤出现了次生盐渍化。
The results showed that: (1) with the increase of planting years, the number of soil water-stable aggregates (5 ~ 0. 25m m) increased, and the capillary porosity was developed , Holding water becomes better; ventilation permeability worse. (2) The contents of organic matter and total nitrogen in greenhouse and open-field soil planted for more than 5 years increased significantly and reached a significant level; the available nitrogen increased significantly and reached a significant level; the available phosphorus was highly enriched; However, there is no obvious change in Harbin, but Daqing is in a state of enrichment. The value of p H decreases with the increase of planting years. (3) Secondary salinization occurs in the greenhouse soil planted in Harbin for more than 8 years.