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以大豆(S)、玉米(M)、小麦(W)和草本植物(GL)的根际土和裸地(BL)作为处理,研究了不同植物根际土壤团聚体组成、稳定性以及团聚体结合碳的分布。结果表明,草地以水稳性大团聚体(>0.25 mm)占绝对优势,比例达85.9%;与草地相比,农田三种作物处理显著降低了大团聚体的比例,质量分数为68.7%;裸地大团聚体比例(55.7%)最小,尤其是>2 mm的团聚体仅占3.5%。团聚体水稳定性草地最高,裸地团聚体水稳定性最差,农田三种作物处理居中。玉米、小麦和大豆三种作物根际土壤团聚体在组成上并无显著差异,而玉米根际土壤团聚体稳定性显著高于小麦和大豆。草地团聚体结合碳量最高,为36.0g kg-1土,比农田(平均33.9 g kg-1土)和裸地分别高出5.8%和16.7%。大团聚体(>0.25 mm)是有机碳存储的主要部分,因此保护和维持这部分团聚体的数量和稳定性对于抵押CO2排放和土壤肥力的可持续发展具有重要意义。
The rhizosphere soil and bare land (BL) of soybean (S), maize (M), wheat (W) and herbaceous plant (GL) were used to study the composition, stability and aggregates of aggregates Combine carbon distribution. The results showed that the water - stable macroaggregates (> 0.25 mm) accounted for 85.9% of the total grassland. Compared with the grassland, the three crops significantly reduced the proportion of large aggregates with the mass fraction of 68.7%. The proportion of bare large aggregates (55.7%) is the smallest, especially> 2 mm aggregates accounting for only 3.5%. Aggregate water stability was the highest in grassland, water stability was the lowest in bare soil aggregates, and the three crops in farmland were in the middle of treatment. The rhizosphere soil aggregates of corn, wheat and soybean did not show significant differences in composition, while the stability of corn rhizosphere soil aggregates was significantly higher than that of wheat and soybean. Grassland aggregates had the highest combined carbon content of 36.0g kg-1 soil, which was 5.8% and 16.7% higher than that of farmland (average 33.9g kg-1 soil) and bare land respectively. Large aggregates (> 0.25 mm) are a major part of organic carbon storage, therefore protecting and maintaining the quantity and stability of this fraction of aggregates is important for the sustainable development of collateral CO2 emissions and soil fertility.