以长期定位施肥的蔬菜保护地土壤为材料,研究了不同施肥处理对土壤微团聚体组成和有机质含量的影响.结果表明:保护地土壤中微团聚体的优势粒级是10~50 μm,次优势粒级是50~250 μm.与对照比较,施用化肥各处理土壤<10μm微团聚体含量略有增加,10~250 μm微团聚体含量显著增加;与施用化肥比较,长期施用有机肥或有机肥与无机肥配施处理,土壤<10 μm微团聚体含量减少,10~250 μm微团聚体含量增加,土壤结构系数提高,<10μm和>10μm的微团聚体的组成比例显著降低,以有机肥与氮磷钾化肥配施处理变化最明显.长期施用化肥各处理,土壤有机质含量、易氧化有机质和难氧化有机质含量明显减少;有机肥与化肥配合施用处理,土壤有机质含量、易氧化有机质和难氧化有机质含量明显增加,其中以有机肥与磷肥配施增加最显著.相关分析表明,有机质含量与<10μm微团聚体含量呈现显著负相关.
The results of tained from a sheltered vegetable field that 10-50μm micro-aggregate was primary and 50-250μm was next in the treatments of long-term application of organic plus chemical fertilizers. Compared with the contrast, 〈10p, m micro-aggregate and 10-250μm micro-aggregate increased constantly among different chemical fertilizer treatments. Compared with the chemical fertilizer treatments, a long-term application of organic plus chemical fertilizers made 10-250μm micro-aggregate increased constantly and 〈10μ m micro-aggregate decreased, soil coefficient of structure increased and the proportion of (〈10μm)/(〉 10μm) micro-aggregate decreased. The changes of organic plus N,P,K chemical fertilizer treatment were significant. In long-term applications of chemical fertilizer treatments, the contents of O.M.,readily oxidizable O.M. and difficultly oxidizable O.M. decreased, but the contents of O.M. readily oxidizable O.M. and difficultly oxidizable O.M. increased constantly among organic plus chemical fertilizers. Organic plus P chemical fertilizer treatments were significant. Analysis showed that the content of organic matter was negatively corelated to 〈10μ m micro-aggregate.