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本文研究了强度耕作后,土壤各级不同大小团聚体的稳定性,密度,孔隙度以及保水性和养分含量的变化。常规耕作土壤中的团聚体较未耕的或少耕土壤中的团聚体的密度稍大,孔隙较少,稳定性较差。常规耕作使大团聚体量减少。在有的土壤中,少耕和常规耕作后,大团聚体的比例没有不同。常规耕作土壤中的干团聚体,遇水后崩解得最多,没有耕的土壤中的团聚体崩解得最少。未耕和耕作土壤中干的大团聚体(>0.25mm)的比例分别为90和71%。耕作土壤中所有各级大小团聚体中碳和氮的含量都较未耕土壤少。
In this paper, the stability, density, porosity, water retention and nutrient content of aggregates of different sizes at different soil levels were studied after intensive tillage. The aggregates in conventional tillage soil were slightly denser, less porous and less stable than the aggregates in the uncultivated or tillage soils. Conventional farming reduced the amount of large aggregates. In some soils, there is no difference in the proportion of large aggregates after tillage and conventional farming. Conventional tillage soil in the dry aggregates, water disintegration after the most, unpolluted soil aggregates collapse the least. The proportions of large dry aggregates (> 0.25 mm) in uncultivated and tillage soils were 90 and 71%, respectively. Cultivated soil at all levels of size aggregates of carbon and nitrogen content than the uncultivated soil less.